issues/case studies - Henriksen Science · 8/1/2011 · tions shaped Earth long before humans evolved. These powerful natural events can cause immense destruction, and humans have

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Environmental science

issues/case studies

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Contents

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Issue 1: Should Monitoring Volcanic Activity Be An International Effort? 3

Issue 2: Can Scientists Work in the Oceans Without Disturbing the Neighbors? 5

Issue 3: Global Warming: A Heated Debate 8

Issue 4: Should Alien Species Be Introduced to Ecosystems? 11

Issue 5: Should Legislation Protecting Coral Reefs Be Strengthened? 14

Issue 6: Can Exxon Be Excused? 16

Issue 7: Should Levees Be Used to Control Flooding? 18

Issue 8: Is Food Irradiation Safe? 20

Issue 9: Should Restrictions Be Used to Revive Declining Fish Populations? 22

Issue 10: Should the United States Promote Aquaculture? 24

Issue 11: Should Traditional Chemical Pesticides Be Banned? 26

Issue 12: Should Governments Invest in “Green” Cars? 29

Issue 13: Nuclear Waste Disposal: Where and How? 31

Issue 14: PAMS and Soil Erosion Control: Are Synthetic Methods the Remedy? 33

Issue 15: Toxic Wastes in Noxubee County: Economic Opportunity or Exploitation? 35

Issue 16: Super Trash Bin or Environmental Trash Pit? 37

Issue 17: Are Large-Scale Water-Diversion Projects the Answer for a Thirsty World? 39

Issue 18: Is Burning the Best Way to Clean Up Oil Spills? 42

Issue 19: Is Ozone Depletion a Serious Problem? 44

Issue 20: Free-market Environmentalism: Is Trading Emissions Permits Just Selling the Right to Pollute? 47

Issue 21: Are Antismoking Laws Justified or Too Restrictive? 49

Issue 22: Should the Endangered Species Act Be Strengthened? 51

Issue 23: Do “Pay-As-You-Throw” Programs Pay Off? 54

Issue 24: Should Lobbying Be Restricted? 56

Issue 25: Risk Assessment 58

Answer Key 60

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E arthquakes, floods, and volcanic erup-tions shaped Earth long before humansevolved. These powerful natural events

can cause immense destruction, and humanshave never been able to prevent them. Scienceand technology cannot stop volcanoes fromerupting or geologic activity from shaking theground. Sometimes, however, scientists canpredict when a volcano will erupt and can issuea warning in time to save lives.

Volcanologists use many tools and methodsto detect and predict volcanic activity. Scientistsstudy magma, hot molten rock in the volcaniccrater, to make predictions. Gases are normallyemitted from volcanoes. As magma wells up ina volcano, the pressure in the crater drops, andgases escape. Measuring changes in volcanicgases such as sulfur dioxide may help predict aneruption. Chemical sensors attached to air-planes detect increases in sulfur dioxide, indi-cating the magma is nearing the surface.Seismometers measure tiny shakes in the vol-cano caused by the movement of magma. Videocameras can also be used to measure the colorand shape of the fumes, and laser-based devicesdetect bulges in the mountain too small to seewith the naked eye.

Scientists around the world are urging theirgovernments to support further research in vol-cano protection. An international conferencewas held in 1988 entitled “Toward Better Coex-istence Between Human Beings and Volcanoes.”Participants declared that an international effortin volcano research should be “of the highestpriority.” Their goal was to form a centralizedinternational headquarters for monitoring volca-noes around the world. The experts called forbetter monitoring systems to predict volcanicactivity and better evacuation procedures toprotect human lives.

Prediction Saves Lives

The primary goal of volcano research and acentralized monitoring of volcanoes is to savelives. The more accurately scientists can predict

volcanic eruptions, the better they can advisethe public on proper procedures, includingevacuation. Advances in volcanology haveimproved the accuracy of predicting volcaniceruptions. Since 1980, Mount Saint Helens inthe State of Washington has erupted 22 times, 19of which were predicted. Improved predictionand evacuation procedures have also savedmany lives. A 1972 eruption of Mount Unzenin Japan killed 15,000 people; when the samevolcano erupted in the summer of 1991, 35 liveswere lost. The smaller number of casualties wasdue to prediction and evacuation procedures.

In monitoring a volcano, scientists hope toassess and minimize the risk of eruption to thesurrounding community. The risk is defined asthe probability of eruption multiplied by theexpected damage. Since no techniques have yetbeen developed to prevent a volcano fromerupting, the only way to minimize risk is tominimize the expected damage to a community.Careful monitoring of volcanic activity keepsthe community informed about the possibilityof an upcoming eruption, giving people time toevacuate and reducing losses.

Scientists can also prevent devastation ofentire villages by diverting the lava stream oncea volcano has erupted. By studying the uniquecharacteristics of the volcano and simulating aneruption, scientists can predict the probablepaths of lava flow. A simulation for Mount Etnain Italy made in December 1991 determinedthat a village of approximately 7000 residentswas at risk. Dams were built that would containthe lava and divert its natural flow. When themountain erupted, causing 473 days of contin-uous lava flow, the village was spared.

The Costs of Making Predictions

The work of predicting volcanic eruptions isvery dangerous, especially when scientists mustenter the volcano’s mouth to collect data. OnJanuary 14, 1993, six scientists were killed andfour more were injured while on a field trip tothe Galeras volcano in Colombia. The scientists

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Issues and decisions 1

should monitoring volcanic activity be aninternational effort?

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were attending a United Nations conference inPasto, Colombia, and wanted to test new meth-ods of volcanic-activity prediction on Galeras.While the scientists were setting up their equip-ment, the volcano erupted, injuring or killingall the scientists on the team. Two months later,two young researchers at an institute inEcuador died while photographing debris froman eruption just three days prior to their trip.The volcano erupted again as they worked atthe site. Since 1951, 27 volcanologists have losttheir lives studying volcanoes.

Predictions of volcanic eruptions are notalways accurate. Even with the most sophisti-cated equipment, prediction is difficult, becauseeach volcano has its own unique internal“plumbing.” Inaccurate predictions followed bywarnings may cause needless evacuations. In1976, 72,000 residents of the Caribbean islandGuadeloupe were evacuated for severalmonths; the nearby volcano never erupted.

Opposition to CentralizedPrediction

The main opposition to a centralized vol-cano protection program is economic. Equip-

ment, training, administrative costs, and com-munity education all require generous funding.Many nations with the highest risk of volcaniceruptions are developing countries that cannotfinancially support the monitoring, evacuationplanning, and lava diversion strategies. In thepast 400 years, an estimated 546,000 deathshave been blamed on volcanoes. Since fewerdeaths worldwide are due to volcanic eruptionsthan to earthquakes, some opponents arguethat the money involved in establishing a cen-tralized volcano protection program could bemore wisely spent elsewhere.

Real estate and tourism industries also suf-fer from predictions of a volcanic eruption orwarnings that a volcano could become active. Ifa prediction is incorrect, these industries losemoney, and the overall economy of an areamay lag.

People opposed to a centralized programpoint out that volcanologists already meet atinternational conferences to exchange informa-tion, even without an internationally central-ized headquarters. Critics question whether acentralized program is the best way of further-ing volcano research.

Review

On a separate sheet of paper, answer the following questions.

1. What geological changes take place during a volcanic eruption?

2. What can be done to prevent a volcanic eruption?

3. How can volcanic risks be reduced?

4. What are some drawbacks of volcanological monitoring?

Decisions


1. Who should be responsible for raising funds to support an international volcano project?Should wealthier countries with no or few volcanoes be required to support developingcountries with greater need but fewer funds?

2. Should laws be established to prevent the sale of residential and commercial property inhigh-risk volcano areas? Why or why not?

3. What should be the primary focus of a centralized headquarters for volcanic research?Should more money go to supplying equipment for monitoring volcanoes worldwide, imple-menting better programs for safety procedures and evacuations, or for research on new waysto predict volcanic activity? Explain.

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B eneath the ocean’s surface, visibility islow because sunlight does not penetratewell through water. Many marine ani-

mals have developed echolocation (E-koh-loh-KAY-shun), the ability to use sound to locateother objects in the sea. The animal emits high-pitched sounds that reflect off undersea objects.The echo is detected by the animal’s ear or spe-cial sensory receptor, allowing the animal tolocate the object. Marine mammals, such asdolphins and whales, depend on echolocationto find their way in their ocean environment.

As you might expect, marine mammals arevery sensitive to underwater sounds. In recentdecades, industrial underwater explosions, oilrig construction, ocean drilling, ship engines,icebreakers, submarines, and numerous otherhuman disturbances have created oceanic noisepollution that threatens the well-being ofmarine mammals. Scientists who study thephysics of sound now find that undersea noisepollution can come from sources once believedto be harmless, such as supersonic jets. Scientistsbelieved that the shock produced by a jet flyingat 2.1 times the speed of sound did not pene-trate the ocean to great depths. Recent studieshave shown, however, that such sound-waveshocks reach to a depth of about 2.5 meters (m)and could be heard by marine animals to adepth of about 120 m beneath the ocean’s sur-face. The problem of oceanic noise pollution hasbecome so serious that the U.S. National MarineFisheries Service and the Fish and Wildlife Ser-vice are considering a ban on human-generatedundersea noise that exceeds 120 decibels. Theprohibition would be enforced under theMarine Mammal Protection Act of 1972.

Animals Bothered byUnderwater Noise

Scientists have documented the negativeeffects of human-generated noise on marinemammals. The animals are extremely sensitiveto and bothered by such noise. Beluga whales

produced alarm calls when they heard shipsthat were 80 kilometers (km) away. When theships were 40 km away, the belugas fled. Bow-head whales are known to alter their migrationroutes to avoid coming within 10 km of drill-ship operations, and to be scared off by distantship-engine sounds of only 90 decibels.

Noise pollution also can result in severe,permanent physical damage, and sometimeseven death, to marine mammals and fish. ACanadian research team studied humpbackwhales feeding on plankton in Newfoundland.Nearby, a part of the cove was undergoingheavy blasting to deepen a navigation channel.The researchers found many mature whalestrapped in fishing nets in the cove, an occur-rence more common among young, inexperi-enced whales. Although the scientists freed thewhales from the nets, they were astonished tofind that the same mature whales often becametrapped a second time.

Scientists suspected that the blasting noisehad impaired the whales’ echolocation, makingthem unable to detect the presence of the fish-ing nets. This prediction was confirmed whenthe scientists examined two whales that died:one was found dead in the nets, another diedtwo days after being rescued. In each case, thewhales’ ears were filled with blood and pus andwere badly injured. Scientists concluded thatthe animals were probably deaf when theybecame caught in the nets. The whale that sur-vived two days after its ordeal had probablydied from meningitis, a fatal infection of thenervous system caused by ear damage.

The baiji dolphin, a close, freshwater relativeof marine dolphins, may become extinct due toexcessive human noise in its habitat. The baijilives in the muddy waters of the Yangtze Riverin China. It has adapted to the murky waters ofits habitat by losing most of its eyesight anddeveloping highly sensitive echolocation abili-ties. As the Yangtze River area has becomeincreasingly industrialized and more populatedby humans, the noise on the river has becomeconstant. Once able to locate and swim beneath

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Can Scientists Work in the oceans withoutdisturbing the neighbors?

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unmotorized sailing boats, the dolphins are nowso confused by the roar from the engines ofsteamers, ferries, and barges that they can nolonger differentiate the sounds. The sounds theyemit for echolocation are lost among human-made noise. Over the years, countless baiji dol-phins have been found in the river or strandedon the shore, their bodies cut by ship propellers.Some dolphins drown in fishermen’s nets. Theyeven have trouble locating food.

Today, there are only about 200 baiji dol-phins left. The Chinese are attempting to setaside a part of the Yangtze River as a preservefor the dolphins in hopes that this will save thespecies. Though the efforts of the Chinese mayprotect the baiji dolphins from being shreddedby ship propellers, the preserve will not be ableto shelter the animals from the deafening noiseof the river.

Effects of Noise Ban on ScientificResearch

In October 1993, the American AcousticalSociety met to discuss the problem of oceanicnoise pollution. Experts from many fields—geology, oceanography, climatology, and bio-acoustics (BY-oh-uh-KOO-stiks)—discussed howthe proposed undersea noise limitation of 120decibels would affect their research. Scientistsexplained that the limitation would have devas-tating effects on industry, all but eliminating theexploration and extraction of undersea oil. Thenoise limitation would also severely limit scien-tists’ ability to study the ocean and marine life,because these studies rely on sound.

These scientists dispute the theory thathuman-made noise is harmful to marine mam-mals. Although the proposed 120-decibel noiselimitation would, in air, cause pain in humanears, these scientists point out that an underwa-ter noise of 195 decibels would be needed toproduce similar discomfort. Some scientists havealso noted that the echolocating calls of manymarine mammals exceed the 120-decibel level.For example, dolphin calls have occasionallybeen recorded at 220 decibels, and fin whalecalls at 180 decibels. These scientists point outthat in many places in the ocean, natural sounddisturbances often exceed 120 decibels. Polar icecrashing into the sea, for example, generates150 decibels, and crashing waves on the shoreproduce 130 decibels of sound.

Marine mammalogists are quick to pointout, however, that the calls of marine mammals

and the break-up of polar ice are sounds that donot occur at regular intervals. Though they mayexceed 120 decibels, they are not constant likethe noise generated by human activity.

All bodies of water, whether oceans orrivers, transmit loud, low-pitched noises overimmense distances. Some noises can travelthrough the oceans halfway around the world.Scientists have used this quality of water tostudy a crucial environmental problem: globalwarming caused by the emission of certain pol-lutants into the atmosphere.

The Heard Island experiment, begun in1991, provided useful data about changes in theglobal atmosphere. The experiment is based onthe following principles: the speed at whichsound travels through water is dependent onthe water temperature. By tracking the speedsof loud sounds over a 17,700 km underseacourse, scientists can calculate the degree towhich the oceans are warming. Scientists usedan underwater loudspeaker to emit a 209-deci-bel sound from the deep ocean. This decibellevel is equivalent to 270 decibels in air, theintensity of sound produced when a jetlinertakes off. The sound moved through the oceanand was recorded at sites from Antarctica toAlaska, from Newfoundland to New Zealand.

The first Heard Island experiment was agreat success. Scientists hope to follow it with

Deci

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others, emitting even louder sounds. However,if the new legal limit for human-generatedsound in the oceans is set at 120 decibels, theproject would have to be canceled.

Conflict over the issue of underwater noisepollution seems unavoidable. Most oceanicresearch relies on the production of underwatersound to obtain data. Yet even the “quietest”sounds may bother or severely harm echolocat-ing marine mammals. One scientist said, “Itmay be that the inconvenience of noise tomarine mammals will remain unavoidable, butwe must try to prevent noise that causes sub-stantive damage.” The following lists summa-rize reasons for allowing unlimited underseanoise and those for opposing it.

Arguments for 120-DecibelHuman Noise Limit in Oceans

• Would stop interference with marine ani-mals’ echolocation

• Would stop interference with marine ani-mals’ migration routes

• Scare fewer marine animals from their calv-ing or feeding territories

• Reduce infection, deafness, and possiblydeath among echolocating marine animals

• Would reduce interference with growth andreproduction in echolocating animals

• Could prevent species extinction if noise inhabitat is excessive and constant

Arguments Against 120-DecibelHuman Noise Limit in Oceans

• Would make exploring for and extractingoil impossible

• Would make geological research impossible

• Would make important research on globalwarming impossible

• Would limit research on marine animalsthemselves

• Natural ocean noises often exceed the 120-decibel limit

• Could affect national security by prohibitingthe use of sonar in submarines

Review


1. What is echolocation, and how is it affected by human-generated undersea noise?

2. What are some major sources of oceanic noise pollution?

3. How will a 120-decibel limit on human-generated noise in the oceans affect marine research?

4. Imagine that for some reason humans suddenly had to live in an environment in which theywere constantly surrounded by flashing colored lights. Compare the effects this would haveon people to the effects of underwater noise on marine mammals.

Decisions


1. Considering all the arguments for and against human-generated noise in the oceans, whathuman activities, if any, do you feel could be justified despite their negative effects on marineanimals?

2. Suppose agencies of the United States government have decided to limit noise pollution ofthe oceans to 195 decibels. Why do you think they decided on this limit? What effects do youpredict this legal limit will have on both human activity and marine animals?

3. If you were involved in a government agency’s decision-making process concerning oceanicnoise pollution, what would you recommend? Explain the reasons for your decision.

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L ight from the sun is absorbed by Earthand converted to heat. Some of this heattravels back into space in the form of

infrared radiation. Certain gases in Earth’satmosphere, such as carbon dioxide (CO2), trapsome of this radiated heat, which warms theplanet. The heat-trapping gases, which functionin a manner similar to the way glass does in agreenhouse, are called greenhouse gases. Withoutthe presence of greenhouse gases in the atmos-phere, Earth’s temperature would be about35˚C lower than it is today, and most life formswould probably not exist.

Carbon dioxide is the most abundant green-house gas in the atmosphere, and as such it mayhave the greatest impact on the amount of heattrapped. Methane and oxides of sulfur and nitro-gen are far more efficient than CO2 in trappingheat, but are much less abundant in the atmos-phere. Since the pre-industrial era, atmosphericCO2 levels have risen 25 percent and continue toincrease at a rate of 0.5 percent yearly.

Some scientists project that this increase inCO2 could lead to a general increase in world-wide temperatures ranging from 1.5˚C to 4˚C inthe next 40 years.

Possible Effects of GlobalWarming

The Electric Power Research Institute haswarned, “The sweeping consequences of accu-mulating greenhouse gases in the atmospheremay turn out to be the greatest environmentalproblem of modern times.” If the threat ofglobal warming is real, what kinds of changescan all life on Earth expect?

The warming would affect the seas. TheU.S. Environmental Protection Agency (EPA)predicts a sea-level rise of 0.3 meters in thenext 40 years; 0.6 m to 1.8 m in the comingcentury. The total rise within a few centuriesmight be as great as 7.5 m. Part of this rise insea level would result from the melting of theAntarctic ice sheet, and part of it would be dueto the increased volume of the warmer water.

The majority of people in the United States livewithin 80 kilometers of a coastline, and manyof them would be affected by such a change.Eighty percent of coastal wetlands might also becovered by the sea, and destroyed as wetlandhabitats. A rising sea that covers coastal estuar-ies could cause a drop in the populations ofcountless fish and shellfish species. In the openseas, many species may become extinct as coldocean temperatures rise and ocean currents arealtered. These changes could destroy fisheries,many of which are already on the verge of col-lapse due to overfishing.

Large-scale changes in major land ecosys-tems could also result. One Canadian studyshowed that a 2˚C change in climate tempera-ture over 600 years could result in a 30 percentloss of biomass in temperate forests. As the cli-mate warms, ecosystems would shiftnorthward. Forests could be destroyed as treesbecome unable to adapt to new conditions or toexpand their geographical range quicklyenough. As the climate becomes drier, theforested areas would be taken over by grass-lands. Many kinds of wildlife would likely beunable to migrate to suitable habitats and couldperish. Cold Arctic ecosystems could disappearcompletely if polar temperatures rise and Arcticice melts. Research conducted by the U.S.Department of Energy concludes that globalwarming “may yet overwhelm the life supportsystem crafted in nature over billions of years.”

Many areas of North America, Europe,Africa, and Asia may experience a drasticchange in rainfall as a result of global warming.Major droughts could bring Dust Bowl condi-tions back to the Great Plains of the UnitedStates and devastate the corn belt states of theMidwest. Agricultural production worldwidecould fall drastically.

Evidence of Global Warming

Attempts are now being made to correlatewarming of the climate in the past to increasesin CO2 in the ancient atmosphere. One area of

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global warMing: a heated debate

research involves analyzing the CO2 content ofcores taken from huge polar ice sheets. European scientists found that during the last160,000 years there has been a direct linkbetween atmospheric CO2 levels and higherglobal temperatures.

For years, scientists predicted that plantsand soils would absorb much of the extra CO2that was being released into the atmosphere,because plants use CO2 for photosynthesis. Infact, some studies had shown that plants wouldgrow bigger and better because of the extraCO2. These studies were based, however, onpredictions of what would happen after globalwarming had fully taken place.

More recent studies have concentrated onthe transitional period, before the full impact ofwarming sets in. The newer research demon-strates that in that period, plants and soils willprobably not be able to keep up with the increas-ing amounts of CO2 in the air. There is alreadydirect evidence that this view is correct. In theArctic tundra, where spring snow melt is occur-ring earlier each year, plants and soil are actuallyreleasing more CO2, not absorbing more.

The Call to Reduce Fossil-Fuel Use

Some scientists urge that drastic measuresbe taken immediately to reduce or eliminatefossil-fuel consumption. Others are concernedthat if such measures are taken, the globaleconomy could be devastated, at least in theshort run. Still, many experts claim that theshort-term setbacks would be justified because,in their view, it would help avoid long-term,permanent climatic disaster.

The American Council for an Energy-Effi-cient Economy agrees that fossil-fuel use shouldbe reduced. However, its members have a differ-ent view of the economic results. Their data sug-gest that large reductions in fossil-fuel use couldresult in creation of about 1.1 million jobs by theyear 2010. They argue that as industries increasetheir energy efficiency, the money they save inlower energy costs could be invested in newfactories and equipment, resulting in new jobs.

Opposing Views on GlobalWarming

Although a large majority of scientists thinkthat increasing levels of atmospheric green-house gases pose a serious threat, other scien-

tists do not agree. Some of them suggest thatnatural processes will prevent fuel emissionsfrom causing disastrous changes in world cli-mate. They claim that other factors that willkeep the planet cool may come into play. Theypoint to the example of volcanic eruptions,which spew tons of dust into the atmosphere.The dust prevents sunlight from penetrating theatmosphere, keeping the climate cool. Thesescientists also refer to studies indicating thatgreenhouse gases may increase cloud cover inmany regions. The cloud cover would keep thesunlight out and temperatures cool. Critics ofradical global-warming prevention say societycannot afford to spend so much money to pre-vent a disaster that may not even happen.

Some scientists opposed to drastic reduc-tions of greenhouse emissions also point to evi-dence that the climate of Earth naturally passesthrough cycles. For example, at the time fossilfuels began forming millions of years ago, tem-peratures were quite a bit higher than they aretoday. It is possible, therefore, that the tempera-ture changes seen today could partially be theresult of a natural cycle.

The Problem of Prediction

Some scientists argue that global warmingcannot be predicted with confidence becauseforecasting climate far into the future is toocomplex. The current computer models used topredict global warming may not be able toincorporate and reflect all the aspects of cli-mate patterns.

The problem with using computer models isfurther complicated by another fact. Computermodels are like statistics in that they can bemanipulated to support almost any desired out-come. Thus, scientists who think that globalwarming poses a serious threat may be able toproduce models that are tailored to demon-strate that point.

Scientists convinced that dangerous globalwarming is occurring argue that it is wrong toattack computer model data as nonscientific.They claim that most data manipulation isbeing carried out by powerful groups, such asoil companies, who have an interest in showingthat global warming is not occurring.

Concerned scientists also point out thatpredictions on climate can never be scientifi-cally verified in the same way as a simple labo-ratory experiment. It is impossible to put Earth

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into a test tube and carry out controlled climateexperiments. These scientists, along with manyenvironmentalists, insist that their computerdata are convincing and consistent. In theirview, the consequences of doing nothing andwaiting to see what will happen may be tooterrible to risk.

The Situation in DevelopingCountries

The possible effect of global warming onagriculture in developing countries would bedisastrous, according to three independent scien-tific studies. Global warming could result in dras-tic reductions of food production and increases inhunger in those countries. At the 1992 EarthSummit in Rio de Janeiro, Brazil, many nationsratified an agreement called the Global WarmingConvention. This agreement was designed toreduce greenhouse-gas emissions worldwide.

Many developing countries were offended,however, by some parts of the agreement.Greenhouse gases are produced by industriesthat bring wealth to a nation. The developingnations saw the agreement as an attempt toslow their development by imposing strict stan-dards on greenhouse emissions. These countriesare now demanding aid with emissions-controltechnology to help them raise their standard ofliving without adding to global warming.

Developing nations were also annoyed bythe industrialized countries’ reluctance toreduce their own emissions drastically. Whatright, asked the developing countries, do indus-trialized nations have to forbid citizens in adeveloping country to own cars or refrigeratorsbecause those devices promote global warming?It is clear that the needs of all countries of theworld will have to be assessed before realprogress can be made to diagnose and addressthe problem of global warming.

Review


1. What are some possible environmental effects of global warming?

2. Why do some scientists think it is difficult or impossible to predict the environmental effectsof global warming?

3. Why do developing countries oppose adoption of strict standards on fossil-fuel emission?

Decisions


1. Some states have begun to use revenues from drivers’ licenses, vehicle registrations, andhighway tolls to pay for public mass-transit systems. If you owned a car and drove a greatdeal, would you object to this policy? Why or why not?

2. Think about the changes you might have to make in your life if the government ordered asudden large reduction in use of fossil fuels while developing alternative forms of energy.Also think about the effects such a policy would have on our nation’s economy. Explain whyyou would support or oppose such a policy.


D eliberately or accidentally, manyspecies of plants and animals havebeen transported all over the world

through global trade. Native species exist in anecosystem in a balanced relationship to oneanother. When species are taken from theirnative habitats and transplanted in new ecosys-tems, these species can seriously disrupt theecosystems they invade. Transported species arecommonly referred to as alien species.

Alien species are disruptive because theecosystems they invade often have no way tocontrol them. In balanced ecosystems, predatorsand prey act as controls on each other’s popula-tions. An ecosystem may have no predator thatcan control the population of an introducedalien species.

Alien species may also carry alien diseases.Plant and animal species usually develop someresistance to diseases that naturally occurwithin their habitats. But they usually have noresistance to foreign diseases, and so are easilykilled by them. Finally, in the absence of preda-tors, alien species are often able to outcompetenative species for resources, such as food orspace. Native species may then be pushed out oftheir habitat, and their populations maydecline, sometimes to the point of extinction.

Accidental Invasions

California is a major provider of fresh pro-duce for much of the United States. If you haveever driven to California from another state,you were probably stopped at the border andasked by an official if you had any fruits or veg-etables in your car. The official probably askedyou to give up any fresh produce you werecarrying to ensure that you were bringing in noMediterranean fruit flies. These fruit flies, called“Medflies” for short, pose a major threat to Cal-ifornia crops.

Medflies, native to tropical Africa, landed inHawaii in 1910. These insects soon found theirway to California’s farm fields, where theybegan to devastate crops. Farmers became

involved in a fierce and continual battle, usu-ally involving the use of pesticides, to eliminatethese insects. The Medfly, however, still periodi-cally turns up among the fruits and vegetablesgrowing in California.

Other foreign species have devastated theforests of the United States. Chestnut blight, adisease that has endangered the Americanchestnut tree, is caused by a fungus that growsbeneath the bark of the tree. It was first notedin New York in 1904. The fungus spores proba-bly entered New York harbor under the bark oftrees that were imported from Asia. By 1950,3.5 billion chestnut trees had been afflictedwith the blight.

Another way alien species have traveled toforeign lands is on cargo ships used in interna-tional trade. When cargo ships leave their homeport, they often take on up to 190 million litersof water, which they keep in ballast containers.This ballast helps the ships stay balanced andstable during ocean voyages. When the shipsreach their destination, they release water fromtheir ballasts into the foreign harbor. Some ofthe world’s most serious alien-species problemshave been caused by “stowaways” in ship bal-lasts. For example, scientists sampled ballastwater from 159 Japanese cargo vessels that haddocked in Oregon. They found 370 non-nativeorganisms swarming in the ballast tanks,including fish, plankton, crab and clam larvae,worms, shrimp, snails, and jellyfish. All thesealien species were to be flushed out of the bal-last tanks and into the waters of Oregon’s Coos Bay.

The above examples describe only a few ofthe accidental arrivals of alien species and someof their effects on native species. These species’introduction resulted in serious disruptions ofthe local ecosystems invaded. Not all alienspecies, however, are the result of accidents.

Introducing Alien Species toIncrease Profits

Sometimes alien species are introduceddeliberately into an area to benefit an industry

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should alien species be introduced to ecosystems?


because they have a useful genetic trait. Honey-bees are an introduced species, brought to theUnited States from Europe. The more aggres-sive and more productive wild African beeswere imported into Brazil in 1956. Scientistshoped the honeybees and African bees wouldinterbreed, creating a more productive, yet gentle hybrid. Because African bees come froma harsh, drought-stricken land where resourcesare few, they have become aggressive to protectfood resources. They use an aggressive mobbingstrategy to protect the flowers they find. Africanbees have been known to mob small animalsand sting them to death. That is how theybecame popularly known as “killer bees.”

Since the introduction of African bees,honey production in Brazil has increased six-fold. Some believe this increase is due to thehigher productivity of the African bees. How-ever, the hoped-for hybrid of honeybees andAfrican bees—a bee that would be both gentleand productive—has not materialized.

During the experiments, some African beesaccidentally escaped. The African bees haveoutcompeted the honeybees wherever the twospecies met. The African bees have sinceexpanded their range northward through SouthAmerica, Central America, and Mexico intoTexas and other southwestern states.

In another example of introducing alienspecies, a court in Brazil recently approved thebreeding of Nile crocodiles at a “leather ranch”near the Pantanal River system leading to theAmazon River. The Nile crocodile is highlypredatory, responsible for dozens of humandeaths in its native Africa each year. The crocswere imported to Brazil so they could be raisedto 18 months of age, at which time they wouldbe killed and skinned. Their skins would beexported for the making of leather products. Incourt, the importers argued that the securityaround the ranch where the crocs are beingbred is equivalent to that of a “nuclear installa-tion.”

Still, ecologists are concerned about theeffects on the fragile Amazon ecosystem if thisdangerous crocodile manages to escape. Theecological effects of an uncontrolled predator asaggressive as the Nile crocodile would havecatastrophic impacts on the Amazon ecosystem,already threatened in many places. So greatwould be the impact on the countless species ofthe Amazon, scientists are comparing the prob-

able escape of the Nile croc to “storing pluto-nium in Grand Central Station.”

The croc’s importers insist that “maximumsecurity is [their] main concern” and that theyare “not introducing an exotic species because[the crocodiles] are in captivity.” The importersreport that they are trying to establish a leatherindustry in Brazil and make a living. A croco-dile specialist countered with the observationthat of all the crocodile farms he has visited, hefelt that none was completely secure.

Introducing Alien Species forRecreation

Many states in our nation obtain incomefrom the sale of fishing permits and frommoney spent by fishers in local communities. Topromote sport fishing, these states stock theirlakes, streams, and rivers with fish speciesattractive to fishers. Often, however, thesespecies are not native to that state. Their intro-duction may disrupt aquatic ecosystems andlead to the endangerment or extinction ofnative fish.

Federal government reports on the effectsof stocking game fish indicate that two-thirdsof the fish extinctions that have alreadyoccurred in the United States were due to theintroduction of alien species. Of those 850native fish species still thought to exist, morethan one-third are now considered rare, near-ing extinction, or possibly already extinct. Fullyhalf of the fish on the federal endangeredspecies list are being outcompeted by intro-duced species.

The effects of introduced species are oftenunforeseen. For instance, Montana introducedan alien freshwater shrimp into the tributariesof Flathead Lake, hoping that the shrimp wouldfatten up game fish. The shrimp quickly spreadinto the lake, where they consumed most of thenative zooplankton. This left little food for thenative kokanee salmon, which feed on zoo-plankton. The salmon population crashed, fol-lowed by the bald eagle population, whichdepends on salmon as a food source.

Benefits of Introducing AlienSpecies

Fisheries managers in most states defendtheir fish-stocking practices. They refute theargument of environmentalists that waterways


should contain only native species. They pointout that most aquatic ecosystems have alreadybeen altered and have adjusted to these alter-ations. Managers also point out that, becausethey have to compete with other states toattract sport fishers, they are forced to stockbodies of water with the most sought-after fish.The money that states collect from fishing per-mits and vacationers is crucial in maintainingfisheries and wildlife programs in most states.Without this money many states would beforced to severely curtail management and pro-tection of state parks, wildlife areas, and water-ways.

In addition to recreation, the introductionof foreign species can boost the economy of the

country that imports the organisms. Theincreased production of the African bees andthe skins of the Nile crocodiles can help indus-tries prosper. These introduced species maybenefit the economy as long as they can becontained or controlled so that they will notdisrupt the ecosystem.

If carefully monitored, an alien species mayhelp return the balance of an ecosystem thatwas disrupted by some other cause. Predatorspecies may be imported to control a popula-tion of pests. Other organisms may be intro-duced to control certain types of pollution.Whether or not the alien species can be con-trolled is an important consideration; accidentalinvaders can harm an ecosystem.

Review


1. Why do officials in California monitor the transport of fresh produce in the state?

2. How have ship ballasts created some of the world’s most serious alien-species problems?

3. How did the introduction of the African bee affect honey production in Brazil? Why are somepeople concerned about using the African bee for this purpose?

4. Why do fisheries stock game fish in bodies of water where these fish species are not normallyfound? What effect could these fish have on native fish species>

Decisions


1. If you were a state official involved in the management of state parks, would you approve ofstocking waterways with alien fish species? Why or why not?

2. Farmers in the southeast United States imported and planted the kudzu plant to help controlsoil erosion in the fields. Since then, kudzu growth has been unstoppable and has taken overmany agricultural areas. Recently, however, scientists found that kudzu contains a substancethat is an effective treatment for people who are alcohol dependent. What do you thinkshould be done about growing kudzu plants in the United States for this purpose?


C oral reefs are often regarded as themarine equivalent of tropical rainforests. Both kinds of environments

exist only in warm, tropical regions and dependon direct sunlight year round. Both representdiverse ecosystems with many unique species oforganisms. Although coral reefs occupy only 1percent of the ocean, one-third of all marinefish depend upon the reefs for survival. Manyspecies of reef organisms have yet to be identi-fied, and some may prove useful in science andmedicine. Yet coral reef preservation rarelyreceives the degree of attention given to savingthe rain forests.

Coral is actually the remains of tiny animalscalled polyps living together in colonies. Theyexcrete calcium carbonate to form a toughlimestone exoskeleton on the reef surface,within which they spend their entire lives.Polyps extend their stinging tentacles to catchand feed on plankton that float by. Since theenvironments in which they live have limitedplankton content, polyps supplement their dietby living with single-celled algae called zooxan-thellae (ZOO-oh-ZAN-thuh-lay). Polyps andzooxanthellae share a symbiotic relationship.Polyps benefit from the oxygen and organicnutrients provided by zooxanthellae, and inreturn provide shelter and carbon dioxide forthe algae.

A coral reef develops over thousands ofyears. Damage to a coral reef can take years,decades, or even centuries to repair. Naturalerosion of the limestone sets back the growth ofthe reef, so coral must continue to grow tomaintain the reef. If the coral’s growth were tobe slowed, erosion would eat away at the reef,reducing the amount of coral and upsetting theecosystem.

Threats to Coral Reefs

Coral reefs are experiencing the problem of“bleaching.” The normally purple, red, andbrown hues of coral are caused by the presenceof the algae living inside them. When coral is

harmed in some way, its polyps expel the algae.The coral turns white as it loses its symbioticpartner. Since much of its food supply has beenlost, the coral’s growth is substantially slowed.Bleaching was first spotted in the Florida Keysin 1918, but it was not until massive outbreaksof bleaching were observed in the 1980s thatscientists became alarmed.

A possible cause of bleaching is globalwarming. Coral can survive only in the narrowtemperature range of about 21˚ C to 29˚ C.Warming of the oceans stresses coral, causingpolyps to expel cohabiting algae. A coral reefcan usually recover from bleaching; once thestress is gone, algae return to the coral.

Another possible cause of reef bleaching ispollution. Toxic chemicals in sewage and othersources of pollution can kill the tiny algae. Other pollutants, such as fertilizers, supplynutrients to the otherwise nutrient-poorwaters. This pollution causes an overgrowth ofalgae, which clouds the water, preventing sun-light from reaching the coral reefs. The lack ofsunlight halts photosynthesis by the zooxan-thellae, slowing coral growth.

Coral reefs have been damaged extensivelyby commercial activities of the coastal nationswhere reefs occur. Seafaring vessels dropanchors on reefs, smashing the coral. Largeships occasionally hit reefs and wipe out thou-sands of square meters of coral. Small fishingboats that help support the economy by har-vesting reef fishes can also destroy chunks ofcoral. The collecting of tropical fish for homeaquariums is another industry that contributesto reef destruction while supporting localeconomies. Tourism also accounts for much ofthe destruction. Many tourists illegally takepieces of coral as souvenirs.

Environmentalists wish to strengthen lawsto protect United States coral reef environments.The states’ governing jurisdictions extend up to4.8 kilometers offshore. Federal or internationalmandates would be necessary to protect reefsworldwide from damage caused by human activ-ities. Many want the entirety of the only barrier

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should legislation protecting coral reefs bestrengthened?

reef in the United States, located off the coast ofFlorida, to be declared a federal sanctuary.

Benefits of Legislation

Legislation could protect reefs from theeffects of further human activities. Aside fromsupporting a highly diverse group of marineorganisms, coral reefs affect Earth in other ways.When coral polyps produce calcium carbonatein making their limestone exoskeletons, largeamounts of carbon dioxide are fixed in theoceans. If the reef ecosystems were destroyed,the carbon dioxide cycle would be affected.Atmospheric levels of carbon dioxide wouldincrease, adding to global warming.

Coral reefs, like rain forests, have practicaluses and benefits to humans. Reefs protectcoastal areas from storm damage; where reefsare destroyed, human-made barriers are neces-sary. The reef environment supports the fishingand tourist industries of many tropical nations.

Problems with Legislation

Since the cause of coral-reef bleaching isstill in dispute, the type of legislation needed toprotect reefs cannot yet be determined. If thebleaching is a natural event, legislation will nothelp the problem.

As with all environmental issues, imple-menting programs to protect coral reefs wouldbe costly, and proper enforcement would beneeded. Funding would be needed for furtherresearch on the status of the reefs and theimpact of regulation. Many people in the trop-ics depend on the coral reef environment fortheir livelihood. These ecosystems provideseafood and stock the tropical fish trade.Tourism is also a major money-maker in theregions surrounding reef ecosystems. If strictregulations prevented such activities, theeconomies of these regions would likely suffer.


Review


1. How are coral reefs similar to tropical rain forests?

2. Describe the symbiotic relationship involved in coral reefs.

3. What is the cause of the warming trend in Earth’s oceans?

4. How are people disrupting coral reef ecosystems?

5. How do coral reefs benefit people?

6. What are the difficulties in establishing legislation to protect coral reefs?

Decisions


1. One problem with the preservation of coral reef environments is overfishing. Keeping inmind that many nations are financially dependent on fishing industries, what can be doneabout regulating the fishing of the reefs?

2. To help replace damaged coral reefs, some scientists think that artificial reefs could provide asolution. Artificial reefs are made by dropping discarded appliances, used automobiles, oilplatforms, or sunken boats to provide shelter and increase the variety of fish and the biomassof marine organisms. What might be bad about creating artificial reefs? Do you think theywould be an acceptable solution? Why or why not?

3. Since all nations share the planet’s oceans, it might make sense for countries to agree oninternational regulation of oceanic waters. What might be the advantages of such regulation?Who do you expect might oppose international agreements?


I n the spring of 1993, scientists gathered toshare information on the status of PrinceWilliam Sound in the wake of the Exxon

Valdez oil spill of March 1989. The status of theSound stirred an energized debate, in which thescientists were divided according to two oppos-ing points of view. One faction took the stancethat the Sound was recovering amazingly well.The other view was that the Sound was stillseriously damaged and would not recover formany years.

The two groups have completely differentopinions about the same study area and aredivided over the results of research conductedby Exxon and research conducted by theNational Oceanic and Atmospheric Administra-tion (NOAA). This heated debate also extendsto the question of who bears the responsibilityfor cleaning up Prince William Sound. There isabout $2.4 billion in spill-related damages to becovered and an additional $900 million cleanupfund to be financed. The class-action suit inwhich the $2.4 billion would be claimed by 40,000 Alaskan natives, fishers, and other indi-viduals, was to go trial in June 1994.

One of the issues disputed by the scientistsis Exxon’s use of a laboratory technique called“hydrocarbon fingerprinting” to show thatorganisms contaminated by oil in the Soundwere actually affected by oil that came fromsources other than the Valdez spill. Hydrocar-bon fingerprinting is commonly used in oilexploration to determine which deposits areproducing which types of crude oil. It identifiesthe different types of hydrocarbon molecules incrude oil and matches them to a known pointof origin. For example, an analysis of the crudeoil that was pumped out of a well in a placecalled Oil Town showed that Oil Town crudewas 17 percent molecule A, 53 percent mole-cule B, and 24 percent molecule C. If oil sam-ples taken from various areas showed the samepercentages of molecules A, B, and C as the OilTown crude oil, one could assume the oil sam-ple’s origin was the Oil Town deposit.

Valdez Studies

Exxon researchers tried to match the finger-print of Valdez crude oil to 5000 oil samplescollected from animals for analysis by theNOAA. This study was conducted to determinethe extent to which oil from the Exxon Valdezcontaminated the organisms of Prince WilliamSound. The study showed that only a verysmall percentage of the samples containedcrude oil that could be matched with Valdez oil.These matches were made among samples thatwere collected in 1989. Very few samples from1990 were matches, and no samples from 1991were reported to match the Valdez oil. Exxonclaimed that any reports showing an extensivepresence of Valdez oil were a result of misinter-pretation on the part of NOAA researchers.

Further studies also support claims byExxon researchers who state that PrinceWilliam Sound has been subjected to oil pollu-tion for more than 150 years. Features knownas oil seeps occur naturally in areas over oildeposits. Many oil seeps around the Gulf ofAlaska have been mapped and fingerprinted.These seeps are the result of oil leaking out ofsediments on the Gulf floor and floating upthrough the water. Analyses of oil samplestaken from the Sound matched the fingerprintsof the oil seeps. Exxon researchers provided anexplanation of how these oil seeps were carriedinto the relatively quiet waters of the Sound.

Studies concluded that most of the oil indeep areas must have come from the seeps.Areas of shallower waters within the Soundshowed the presence of diesel oil, which is usedto fuel tankers and local boats. The combinationof these two oil sources provided a fingerprintvery similar to the fingerprint for Valdez oil.Again, Exxon researchers claimed that NOAAresearchers must have mistaken the fingerprintof this combination for that of Valdez oil.

NOAA Studies

NOAA researchers maintain that the“hydrocarbon fingerprinting” technique is not

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can exxon be excused?

useful for determining the origin of oil contami-nants in organisms. Hydrocarbons are brokendown, or metabolized, by organisms into mole-cules that are no longer the same as the mole-cules that first entered the organisms. Thus, it isvery difficult to support or deny any claimsbased on matching fingerprinted oils with oilsfound in contaminated organisms.Furthermore, NOAA scientists state, deepwateroil seeps cannot account for the oil pollution inthe shallow waters of the Sound.

Other studies conducted by the NationalMarine Fisheries Service and an independentconsultation firm view the Exxon studies withsuspicion. The author of the Marine Fisheries

report is uncomfortable with the idea that theoil seep–diesel oil combination could accountfor the Valdez-like fingerprint in the absence ofValdez oil. If this idea is accepted, then finger-print explanations could easily be used to coverup any evidence of Valdez oil in the Sound.

The independent firm claims that many ofthe reports on wildlife contamination by Exxonresearchers ignore the results of longer andmore extensive studies conducted on the areaby independent researchers. Some claims statethat the Exxon researchers chose only thosesamples and results from wildlife studies thatwould support Exxon’s claims of a quick andthorough recovery from the oil spill of 1989.


Review


1. What is hydrocarbon fingerprinting?

2. What are the two main opposing views on the status of Prince William Sound?

3. What factors make it difficult to specifically identify Valdez oil with Prince William Sound?

4. What is the drawback to identifying the origins of oil contaminants in organisms?

5. What issue do you think is being discussed in this article?

Decisions


1. Why do you think the studies conducted by Exxon researchers are viewed with suspicion?What opinions did you have about the Valdez oil spill prior to reading this article? Explain.

2. If you were an impartial judge, what additional information would you request from Exxonand NOAA so that you could make a fair and sound decision on the class-action suit againstExxon?

3. Predict what might happen if the class-action suit against Exxon was dropped and no finan-cial settlement was made. If you were governor of Alaska, what would you do on behalf ofthe 40,000 individuals who feel they should be compensated for the damages and losses theysuffered due to the spill?


P eople who live in communities alongriver systems risk periodic flooding oftheir cities, towns, and farms. Lives may

be lost and property damage can reach millions,even billions, of dollars. As more communitiesestablish permanence along river systems, theneed for flood control becomes urgent. Formany years, the most common method of floodcontrol has been the construction of levees anddikes along river systems.

Levees are walls built along stream chan-nels to hold in high waters. Dikes are usuallysmaller walls built along small channels thatdivert some of the flow away from the mainstream channel. A system of dikes helps todecrease the volume of water in the mainstream channel, reducing the danger of flood-ing. During periods of normal flood levels, asystem of dikes and levees is effective in main-taining stream boundaries and minimizing thedangers of flooding. During periods of record-level flooding, however, the effectiveness oflevee systems is questionable.

The Mississippi River Watershed Flood of1993 was the most recent test of the effective-ness of levees. When levees were topped orbreached by record-level flood waters, manypeople blamed the extensive flood damage thatresulted on the levees themselves. The U.S.Army Corps of Engineers, which is primarilyresponsible for the design and construction oflevees along major waterways, was heavilycriticized. Civic leaders, environmentalists, andcivil engineers clashed over the advantages anddisadvantages of constructing levees.

The Case for Levees

In 1992, a federal task force reported thatwithin 17,000 communities across the UnitedStates, 59,000 hectares of land are part of afloodplain. About 10 million households nowexist on floodplains, accounting for some of thenearly $390 billion worth of property alongriver systems. The Army Corps of Engineers hasbuilt approximately 16,900 km of levee and

dike systems along these rivers to control floodsand protect developments.

Levees provide protection from normalflooding that occurs almost annually in citieslike St. Louis and Des Moines. Moving citiesaway from rivers is not a workable option.Families and their farms have existed along theMississippi River Valley for generations. Manyriver-valley property owners feel that they areentitled to federal protection, like owners ofcoastal properties that are subject to hurricanes,or owners of property in earthquake zones.

The potential for periodic record-levelflooding is viewed by some people as a possiblestimulus for local economies. Flood controlprojects provide jobs and stimulate businesses.Already, more than $8 billion has been spent onflood control projects for the Mississippi Riversystem. The damage and loss caused by floodingmay be offset by new development and rede-velopment of damaged property.

Natural Flood Control vs. Levees

Natural flood control systems use vegeta-tion and floodplains to capture excess waterand reduce stream-flow energy. This approachallows flood waters to spill out over floodplainsnaturally and reduces the threat of major flood-ing further down the river. During the flood of1993, levees kept the stream flow inside thestream channels of the upper Mississippi River.High flood waters accumulated there, and floodenergy traveled farther down the river. Somepeople think that the levees upstream storedthe stream energy that eventually burstthrough the levees downstream.

After a flood in 1984 killed 13 people andcaused nearly $200 million of property damagein Tulsa, Oklahoma, city planners and the U.S.Army Corps of Engineers developed a naturalflood control system. A string of lake basins wasdug out along the Mingo Creek floodplain andconnected to a system of flow channels. Duringfloods, the string of lakes stores flood waters,

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should levees be used to control flooding?

reducing the downstream flow. This systemrequires developers to include flood water“catch ponds” as part of their developmentdesigns. Catch ponds offset the increased flowthat devegetation and paving can cause. Cityplanners and the Army Corps of Engineers considered this natural flood control systemsuccessful after the Mingo Creek area did betterthan expected during storms that would otherwise have caused severe flooding.

Ecological Dangers Posed by Levees

Environmentalists point out that construc-tion of levees results in loss of ecologically valu-able wetlands. During annual floods, water

normally spills over riverbanks onto floodplains.The natural flood cycle nourishes wetlands andriver-system habitats by spilling fresh water andnutrient-rich sediments onto the floodplain. Thisnatural cycle makes floodplain ecosystems someof the richest and most productive in the world.

When levees are built along rivers, theyprevent the natural flood cycle from spillingwater and nutrients onto the floodplains. Lev-ees also present a threat to endangered species.About half of the endangered species in theUnited States depend on water and nutrientsfrom coastal and floodplain wetlands. If leveeconstruction were prohibited or reduced, thethreat to these endangered species would belessened.

Review


1. What are levees, and why are they constructed?

2. Why might a community object to the construction of levees upstream?

3. How do levees affect floodplain ecosystems?

Decisions


1. Why do you think so many cities are built on the banks of rivers?

2. What changes would be involved in returning the leveed floodplains around St. Louis, Missouri, to their natural condition? Who might object to these changes?

3. The floodplains of many rivers are valuable as farmland because the sediments left by floodwaters enrich the soil. Based on this, do you think levees should be built to protect farmland?Why or why not?



I n the United States, there are at least 10million cases of food poisoning reportedannually due to deadly bacteria such as

Salmonella. About 9000 of those cases are fatal.Medical treatment and loss of worker produc-tivity cost the nation billions of dollars eachyear. During the past several decades, the foodprocessing industry and the federal Food andDrug Administration (FDA) have supported theuse of food irradiation to reduce the danger offood poisoning.

Since the mid-1980s, the FDA has approvedirradiation of a variety of foods—everythingfrom mangoes to meatballs. The prospect of anirradiated food supply has pleased some peopleand alarmed others. Although the practice isbecoming more widespread, food irradiationcontinues to be a controversial topic.

Food is irradiated to destroy harmful bacte-ria or insects in or on the food and to stop thenatural process of ripening. The most commonradiation source used is radioactive cobalt-60.This substance gives off gamma rays, which arelike high-energy X-rays. The radiation dose formost irradiated food ranges from 20,000 to 3million rads (a measurement of radiation). Thelatter figure is about equal to the radiation in150 million chest X-rays. Fruits and vegetablesreceive 200,000 rads to slow down the ripeningprocess. Potatoes are zapped with about 2 mil-lion rads to inhibit sprouting.

During irradiation, gamma rays passingthrough the food break chemical bonds amongatoms and destroy the genetic material inmicrobes or insects, preventing them fromreproducing. Gamma rays also break the bondsof some of the food molecules. However, irra-diated food is not radioactive, just as you arenot radioactive after undergoing dental X rays!Still, the debate rages over the safety of irradi-ated food.

Opposition to Food Irradiation

Opponents of food irradiation point out thatirradiation is not necessary to kill harmful

organisms in food. Proper and thorough cook-ing kills harmful organisms in or on foodincluding both Salmonella and Trichinella, whichcan infect pork and cause trichinosis inhumans. Opponents further point out that irra-diation may actually result in accidental foodpoisoning. In some cases, it may kill organismsthat signal that food has spoiled, without killingother, truly dangerous organisms. A food maytherefore look and smell fresh because theodor-causing organisms have been killed byirradiation. Disease-causing organisms, how-ever, may still infect the food.

Evidence has shown that irradiation lessensthe nutritional value of food by causing a loss ofvitamins. Some people think that this loss ofnutrients in irradiated food may have seriousconsequences. Scientists have noted that foodexposed to gamma rays loses vitamins A, C, andE, and certain B vitamins. One study found thatanimals fed irradiated food lost weight, and thatpregnant animals often miscarried—probablybecause of the food’s reduced vitamin E con-tent. In another study, mice fed irradiatedchicken had unusually short lifespans and weremore likely to develop tumors.

Opponents of irradiation point out that theprocess alters or creates some chemicals in food.As gamma rays break chemical bonds, the freedchemicals can recombine with other substances.The by-products of this recombination are calledradiolytic products (RPs), or free radicals. The pro-duction of RPs in irradiated food is of concern tosome people. When chemical bonds are broken,the number of new RPs that can form duringrecombination is nearly limitless. How, they ask,can tests be made for the toxicity of substancesthat cannot be identified? And, how can it beassumed these substances are safe?

Although these unidentified RPs occur inextremely small amounts, no one knows whateffect they will have as they accumulate in thebody over a lifetime of eating irradiated food.Some of the RPs are known, as are their harm-ful effects. Biophysicists have identified thefollowing RPs in irradiated food: formaldehyde

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is food irradiation safe?

(a known cancer-causing agent formed fromirradiated starch); peroxides (mutagens foundin irradiated plant tissues); and formic acid (amutagen formed from irradiated sucrose).Opponents of food irradiation argue that noamount of a known cancer-causing substance is safe.

Benefits of Food Irradiation

Those in favor of food irradiation point outthe great value and efficiency of irradiation inwiping out harmful insects and microorganismsthat infect food. Irradiated, sterilized food isparticularly beneficial for people whoseimmune system is impaired. In answer to thecharge that irradiation destroys nutrients, theproponents point out that cooking food alsodestroys some nutrients. Also, the nutrient losscaused by irradiation is generally slight. Mostscientists agree that food irradiated with 10,000rads or less of gamma rays shows little or nonutrient loss, even of easily destroyed vitaminC. At greater than 10,000 rads, irradiated foodexhibits nutrient loss that is, according to theFDA, generally no more than the loss thatoccurs in canned or frozen foods.

FDA scientists do admit that some of theRPs that are of concern to opponents are in factknown cancer-causing agents. However, theRPs occur in very minute amounts in irradiatedfood. A 1980 FDA study showed that no more

than 30 parts per million of RPs were found inthe irradiated food tested. Most of these RPsturned out to be identical to naturally occurringfood substances, and so were considered safe.

As for the problem of being unable to iden-tify all the RPs produced by irradiation, sup-porters point out that many substances inunaltered food are unidentified. As abiochemist for the FDA asserted, “You can’tidentify everything that’s in an apple. The basisfor establishing safety is not absolute safety. It’sreasonable safety.”

Food irradiation may make the applicationof harmful insecticides, fungicides, and preserv-atives to harvested foods a thing of the past. Itsuse may therefore reduce or eliminate thesetoxins from the environment. However, pesti-cides that are used during the growth of thefood product may still need to be used.

Grocers, supermarkets, and some poultryproducers may benefit greatly from irradiation.Irradiated food has a much longer shelf-lifethan traditionally treated food. One irradiationcompany official publicly dined on a 14-year-old packaged ham, and proclaimed it “luscious.”By irradiating the meat of chickens and otherpoultry, farmers who raise the birds could avoidthe costs of better hygiene and purer feed.

The controversy over food irradiation may,perhaps, best be summed up by an irradiationproponent who said, “Food irradiation is sogood for food because it is so dangerous foreverything that lives.”

Review

In the space provided, answer the following questions.

1. How does irradiation affect organisms living in or on food?

2. What long-term negative health effects of food irradiation are cited by its opponents?

3. What are the health benefits of food irradiation?

Decisions


1. The FDA requires that all irradiated whole foods display the irradiation symbol—a picture ofa plant set in a broken circle. Yet, packaged foods that contain ingredients that have beenirradiated need not display the symbol. Do you agree with this FDA ruling? How do youthink irradiated foods should be labeled?

2. How do you feel about eating irradiated food? Would you buy irradiated food for yourselfand your family? What information about irradiated food would help you make your decision?



M any people are aware of the deple-tion of natural resources and aretrying to conserve or recycle them.

But most people are not aware of the problemof declining fish populations in lakes, rivers,and coastal waters. Of the 236 fish species inUnited States coastal waters, 67 are being over-fished, and 61 more are in danger of beingoverfished. To help protect the supply of fishand maintain the balanced ecosystem in whichthe fish live, the United States government, aswell as governments of other nations, haveimposed regulations on fishing.

Changes in the sizes of fish populations addto the problem of overfishing. If fish are presentin unusually large numbers for some reason,fisheries invest in more equipment, boats, andworkers to harvest the surplus. Once thesestocks have been used up, the fisheries have tocontinue to make payments for their extraboats and equipment, even though these are nolonger being used. Workers lose their jobs andfisheries often ask the government for financialassistance. These problems could be avoided iffisheries would agree to hold back from intensefishing during times of surplus. This is a lot toask of hard-working people who want to have agood financial year.

Restrictions on Fishing

Determining the maximum number of fishthat can be harvested without seriously affect-ing the population is a difficult task. Fisheriesand federal and state governments rely on rec-ommendations from scientists. Scientists do notalways agree on the causes for the decline ofparticular fish species, and none can predict thefuture of any given fish population with greataccuracy.

Overfishing in the United States is not arecent problem. People were aware of the prob-lem in the late 1800s. As early as 1932, theUnited States and Canada set catch limits to pro-tect the populations of some fish species. In 1976,the U.S. Congress passed the Magnuson FisheryConservation and Management Act. This law

imposed stricter catch limits and shortened fish-ing seasons. Despite these regulations, fish popu-lations of many different species are stilldeclining.

In November 1993, Congress went furtherto regulate catch limits and fishing seasons. Thisnew law focused on the shallow waters of theAtlantic shoreline. Traditionally, the regulationof inshore waters that extend to about 5 kilo-meters from the coastline was left to the states.The federal government formerly had regulatedonly the deeper waters beyond that range, withlaws like the Magnuson Fishery Conservationand Management Act. Because many species ofAtlantic fish migrate, laws need to be standard-ized for all the coastal states. This is usually notthe case. The new federal law requires thecoastal states to agree on fishing seasons andcatch limits for species common to those states.If a state refuses to follow these guidelines, thefederal government has the power to declare amoratorium (MOR-ah-TOR-ee-uhm), demand-ing a halt to all fishing in that state for thoseinvolved species of fish.

The Atlantic is not the only area that isaffected by overfishing and is strictly regulated.Pacific halibut populations off the coast ofAlaska had declined to a point where the fish-ing season was limited to two 24-hour periods.During this short time 600 million pounds ofhalibut were harvested.

Effects of Fishing Restriction

The main purpose of laws that restrict fish-ing is to revive declining fish populations. Theselaws keep the species from extinction and alsohelp conserve a natural resource. Setting catchlimits helps prevent a species from becomingendangered. Shortening fishing seasons allowsthe fish to grow without interference for alonger time.

Some evidence already shows that theseregulations can aid in reviving declining fishpopulations. Many species have been helped byfishing limits. The striped bass population of the

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should restrictions be used to revive declining fishpopulations?

Atlantic and Chesapeake Bay had almost beenwiped out when Congress ordered strict limitson its harvesting. A decade later, large numbersof striped bass now live in these areas and areavailable to recreational and commercial fish-ers, but they are still strictly regulated.

Other marine animals also benefit fromgovernment regulation. The banning of drift-nets protects whales and dolphins. Special netsused in the harvesting of shrimp have “turtleexcluders,” or escape hatches, so that sea turtlesand fish can swim out of the nets. These regula-tions also aim at preserving entire ecosystems,not just a few species of organisms in theecosystem.

Opposition to FishingRestrictions

The major opposition to strict fishing regu-lations comes from the fishing industry. Someopponents doubt that making laws will solvethe problem of declining fish populations,because more factors than overfishing areinvolved in the problem. Many commercialfishers invest large amounts of money in the

boats and equipment used to harvest fish. If thefish season is greatly reduced, they must lay offworkers. A controversial ban on cod fishing inCanada caused 20,000 Newfoundland workersto lose their jobs. If a large percentage of atown’s population is involved in the fishingindustry, the resulting unemployment is likelyto hurt the town’s economy.

When fishing seasons are reduced to veryshort spans of time, as in the case of the Pacifichalibut, other problems arise. These short sea-sons force laborers to work around the clock atan extremely fast pace. Under these exhaustingconditions, work-related accidents and injuriesare more likely to occur.

Overfishing alone is not entirely responsiblefor the declining populations of fish in freshwaters and in oceans. The building of dams cankill fish or prevent them from breeding. Theloss of a species’ habitat due to human activitiesaffects populations of fish. These problems alsoneed to be addressed. Consumers couldbroaden their tastes to include fish species withplentiful stocks, such as mackerel and pollock.There might then be less demand for fish withless plentiful stocks.

23© Addison-Wesley Publishing Company, Inc. All Rights Reserved.

Review


1. How do natural changes in fish populations affect overfishing?

2. How do laws that regulate fishing protect fish populations?

3. How does the 1993 federal law on fishing regulation differ from previous laws?

4. What are the drawbacks to legislation limiting fish catches and establishing shorter fishingseasons?

5. List four reasons why fish populations are declining in lakes, rivers, and oceans.

Decisions


1. Suppose you are a politician representing the interests of a small community whose econom-ic health depends on the fishing industry. How would you approach the problem of the over-fishing of nearby species?

2. Do you think federal laws regulating the fishing industry are necessary? Why or why not?


A s the world’s population continues togrow, so will the need for additionalfood resources. Harm done to the envi-

ronment through careless agriculture and com-mercial fishing practices can result in less foodproduction over the long term. Today, millionsof people are starving. Starvation is not alwayscaused by a shortage of food. Much of the foodthat is given to poor nations remains rotting ondocks because there are no means to transportit to the people who need it. Although somedeveloping nations produce enough food tofeed many of their own people, economic fac-tors force them to export food.

Getting enough protein is the greatestnutritional challenge for starving people. Mostpeople in the United States get much of theirprotein by eating beef and chicken. The averageperson eats only about 7 kilograms (kg) of fish,compared with 31 kg of beef and 29 kg ofchicken. Health experts are now suggesting thatpeople should get more of their protein fromfish. Fish is lower in cholesterol and has fewercalories than beef. Cold-water fish, such assalmon and mackerel, contain large amounts ofomega-3 fatty acids, which may even preventheart disease.

Consuming fish seems to be a good nutri-tional alternative to other sources of animalprotein both in the United States and in devel-oping countries. However, the choice of fish fordinner is generally more expensive than othersources of protein. Many fish species are cur-rently being overfished. Fish populations arealso declining because of dams, pollution, andhabitat loss. The decrease in the supply of fishresources along with the increasing demand forfish creates a problem. Enough fish must beavailable to meet the demand.

Aquaculture, or underwater farming, mayoffer a solution. Fish are raised and harvested inindoor or outdoor tanks or in cages set in lakesor oceans. Freshwater fish, such as pike, perch,bass, trout and catfish, are cultured in thesetanks and cages, as are ocean fish such assalmon, sturgeon, and yellowtail. Crustaceans,

such as shrimp, lobsters and crabs, can also befarmed by these methods. The majority of mol-lusks sold in markets, such as oysters and clams,are raised through aquaculture. Some species ofseaweed can also be raised in warm saltwatertanks or in natural saltwater settings. Seaweedmay not seem like an appetizing alternative tobeef, poultry, or fish. However, some species arevery high in protein, low in fat, and contain alleight of the essential amino acids.

The United States did not experiment withaquaculture until the late 1800s. At that point,people were attempting to increase salmonstocks. It was not until the 1970s that aquacul-ture was actively explored in the United States.

Benefits of Aquaculture

Aquaculture provides a steady supply offresh fish not normally available in natural set-tings. This allows consumer prices to stay low.In many cases, farm-raised fish arrive at mar-kets fresher than fish harvested from their nat-ural habitat. The artificial environments ofaquaculture tanks can be controlled so fish canbe farmed in areas of the world that lack a nat-ural abundance of fish. Certain traits, such asgrowth rate and fat content, can be geneticallycontrolled in farm-raised populations.

The increased production of fish and result-ing decrease in cost to the consumer mayreduce the demand for beef. Raising cattle forbeef can be harmful to the environment. Thelarge amounts of grain required to feed live-stock could otherwise be used to feed people.Tropical rain forests are being cut to make roomfor cattle to graze, placing many species ofplants and animals in danger of extinction. Thewaste products produced by cattle, includingthe release of methane gas from their digestivetracts, contribute to the pollution of the land,water, and atmosphere.

Aquaculture can be a reliable source of pro-tein to feed the increasing human population.Fish farming can also be used to increase fishstocks where needed and may even protectendangered species from extinction.

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should the united states promote aquaculture?

Concerns About Aquaculture

Not all species of fish can be raised by aqua-culture. The ideal aquaculture species is hardyand resistant to disease. It is able to reproduce incaptivity and grow quickly. The cost to feed theanimal must be low and the animal must berather inactive, because confined spaces leavelittle room for movement. Most species do notmeet all of these qualifications, and some aretoo expensive to raise for profit. Lobsters areespecially difficult to raise. Their cannibalisticnature prevents them from being kept in farm-ing groups. They grow very slowly and will eatonly fresh fish.

Disease is often a problem in aquaculture.Because the tanks or cages are so densely popu-lated, diseases are easily spread. Diseases arealso introduced when wild fish are caught andadded to the tanks. Although antibiotics can beused to control the spread of disease, use ofantibiotics results in the development of moreresistant strains of bacteria. Diseases cannot beentirely eliminated.

Animal rights activists object to aquaculturefor several reasons. They point out that the fishare caged in small, crowded areas. The artificialhabitat may interfere with normal behaviorssuch as reproduction. Fish are sometimesinjected with hormones to increase egg laying.

Setting cages in lakes or sea water can resultin environmental problems. The altering of theecosystem due to the presence of cages can beharmful. The waste produced by dense popula-tions of fish can pollute the waters and harm thenatural fish population. The cages are usually setin fast-moving currents to avoid the accumula-tion of waste products in one area. Chemicals,including antibiotics, added to the cages can flowaway and affect the natural fish population.

The escape of farm-raised fish can be dam-aging to surrounding fish populations. In 1990,Norwegian salmon raised in cages had beenselected for fast growth, late sexual maturation,and fat content. Salmon normally return to theirbirthplace to reproduce. When the geneticallyaltered salmon escaped from the cages andinterbred with wild salmon, many of their off-spring were unable to find their birthplace.

The United States falls behind other coun-tries in exploring aquaculture. Industries such asreal estate, as well as coastal residents, object tothe unsightly appearance of cages in coastalareas. Strict government control over the use ofcoastal areas and the initial expense of aquacul-ture prevents many people from investing. Fur-ther exploration of aquaculture as a possiblefood producer in the United States could lead toa healthier, less expensive source of protein. Theestablishment of aquaculture in developingcountries could help fight the war against hunger.


Review


1. Why is fish an excellent source of nutrition?

2. What kinds of food can be mass produced using aquaculture?

3. What is the positive impact of aquaculture on the environment?

4. What is the negative impact of aquaculture on the environment?

5. Why might consumers object to the products of aquaculture?

Decisions


1. As a public official, what obstacles could you face in promoting a federal aquaculture program? What would your program include?

2. Do you think aquaculture could be a profitable investment for private enterprise?

3. If aquaculture were planned on a large scale, what laws would be needed to protect the envi-ronment and the interests of consumers, residents, and other involved groups?


S ince the beginning of agriculture approxi-mately 10,000 years ago, humans havehad to compete with pests such as fungi,

weeds, insects, birds, and rodents. Not until the1800s did farmers begin to use pesticides—chemicals that kill these destructive organisms.The group of chemicals collectively called pesti-cides includes insecticides, which kill destruc-tive insects and their larvae; fungicides, whichkill fungi that infests crops; rodenticides, whichkill rats and other rodent pests; and herbicides,which kill weeds or unwanted plants. For along time pesticides were considered miracu-lous chemicals, not only for protecting cropsand increasing crop yields but also for protect-ing humans from deadly diseases such astyphus and malaria that are spread by insects.The safety of pesticides in regard to humansand the environment went largelyunquestioned until 1962, when a biologistnamed Rachel Carson published the book SilentSpring. In this book she warned that theoveruse of pesticides could be dangerous towildlife. Since then, the controversies havecontinued over the use of pesticides and theirregulation by the United States government.

History of Pesticides

The development of pesticides has beenclosely connected to wartime research. BeforeWorld War II there were only about 30 pesti-cides in use. Today, more than 50,000 types ofpesticides and 1.8 billion kilograms of thesechemicals are used worldwide each year. Theinsecticide DDT was originally created to protectsoldiers from disease-transmitting flies and mos-quitoes. It was initially successful in reducingthe number of cases of malaria worldwide. Italso eliminated the typhus epidemic in Naples,Italy, in 1943 by killing the lice that transmittedthe disease. The herbicide Agent Orange wasinvented to thin out the dense Vietnamese jun-gle during the Vietnam war. Other chemicalsspecifically designed to destroy enemies’ crops,thin jungles, or protect soldiers from insects later

became widely used as pesticides.

Drawbacks of Pesticide Use

The amount of pesticides that the averageperson is exposed to, either by eating producetreated with pesticides, by drinking contami-nated water, or breathing chemically pollutedair, is not usually enough to cause long-termeffects. Those people who handle pesticidesregularly are at a higher risk. Ninety percent of fungicides are suspected oncogens, or tumor-causing chemicals. The National Cancer Insti-tute reported that farm workers exposed toherbicides had a six times greater chance ofdeveloping a particular type of cancer than didthe general public. DDT and its family of pesti-cides are stable, fat-soluble chemicals that donot break down in the body. Instead they accu-mulate in fatty tissues, and over time may causenausea, weakness in the muscles, and convul-sions. Other pesticides are more biodegradable,but are nonetheless toxic. Some cause birthdefects, genetic damage, and other reproductiveproblems, or may interfere with the functioningof the nervous or respiratory systems.

In some instances, the overuse of pesticidescreates pest resistance. Repeated applications ofthe chemicals select for individual insects,weeds, and other pests that possess a naturalresistance to the chemical. These pests multiply,creating a bigger pest problem requiringtougher pesticides (and more expensiveresearch). One case that demonstrated this phe-nomenon was the application of DDT in SaudiArabia in the 1960s to control a malaria epi-demic. Initially it proved very effective; only 17cases of malaria were reported in 1966. By1970, however, 4 million cases were reported.The pesticide was no longer effective against themosquitoes. Even if the pests failed to develop aresistance, they returned to the farms, wherethere was an abundance of food, once the pesti-cide was gone. Since most pesticides kill theinsects’ natural predators as well as the pests,the pests often return in greater numbers than

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should traditional chemical pesticides be banned?

existed before the pesticides were used. Thenstronger pesticides become necessary.

Pesticides may also cause permanent dam-age to ecosystems. Suppose a pesticide seepsinto the soil and is taken up by a plant. If thechemical is not easily broken down, it will accu-mulate in the tissue of the plant. When an ani-mal eats a quantity of these contaminatedplants, the chemical becomes even more con-centrated. Animals at the top of the trophicpyramid are especially at risk because pesticidelevels become most concentrated in them. Theendangerment of these species can then affectthe balance of the entire ecosystem.

Pesticide Regulation

The regulation of pesticides in the UnitedStates was largely ineffective for many years.Initially laws were passed only to ensure thatpesticides were safe and effective. The lawsrequired testing and registration of all thechemicals used in pesticides. The Environmen-tal Protection Agency, however, has been slowto implement these rules. In 1992 a pesticidelaw was passed that focused on worker safety.Employers of farms, nurseries, and greenhousesare now required to train their employees onthe use of safety equipment (such as gloves,goggles, and breathing masks) and the safe han-dling of pesticides. They must also provide theiremployees with access to emergency medicalcare and a place to wash off the pesticide if theycome into direct contact with it. Once an area issprayed with pesticides, signs must be posted towarn workers that it has been sprayed, and noone can be permitted to enter the area for 72hours.

Alternatives to Pesticides

Some people argue that there are plenty ofalternatives to using harmful pesticides and thatthe government should encourage their develop-ment. Biological control is one method. A pest’snatural predator species may be brought in tocontrol the pest population. Predators might beinsects, reptiles, amphibians, or birds. Somepredators are selective, eating only the speciesharmful to the crops. Ladybird beetles (morecommonly known as ladybugs) are a predator

species that controls aphids and scale insects.Insects are not the only pests controlled bypredators; some predator species control weedsas well. However, keeping the predators in thearea once the pests are eliminated is difficult.

Parasites such as different fungi or insectlarvae can also control pest populations. Evendisease-causing microorganisms such as thecommonly used bacterium Bacillus thuringiensiscan be used to wipe out pest populations. Bothof these methods are very specific, killing thepest without harming other species.

Other, nonbiological methods can be usedas alternatives to pesticides. Traps, screens, andelectric “bug zappers” are options, but theseaffect beneficial insects along with the pests.Hormones can be used to interfere with thegrowth and development of either plant orinsect pests. Growing companion species ofplants, such as marigolds, garlic, and mint,alongside crops repels some insects and worms.

Reasons for Using ChemicalPesticides

The agricultural industry has little incentiveto try new methods of pest control or to cutback on its use of pesticides. Sometimes lessharmful alternatives are too expensive or arenot available. The research involved in develop-ing less harmful pesticides is time-consumingand expensive. Farmers are usually subsidizedby the federal government or the chemicalmanufacturers for the use of chemical pesti-cides. Without some form of pest control, theircrop yields drop significantly. With other factorsto contend with such as droughts and floods,farmers look to pesticides as one way of main-taining their productivity.

The cost of research and safety regulationalso keeps pesticides in wide use. The assess-ment of health risks for pesticides is expensiveand difficult, and there is disagreement overexactly how the pesticides should be tested. Forexample, in 1989 the EPA banned the use offungicides containing a specific chemical on 56crops because the residue left on the crops inthe field exceeded the allowable levels. Thechemical manufacturers argued that the levelsof the chemical residues dropped substantiallyby the time the produce reached the market.


After measuring the chemical residues on pro-duce that was to be sold to consumers, the EPAdetermined that 45 of the 56 crops studied hadresidue levels within acceptable ranges, so in1992, the ban on the use of the fungicide onthese crops was lifted.

Laws restricting the use of pesticides arecostly to the agricultural industry eitherbecause they require equipment and trainingrelated to using pesticides safely or because theylead to lower productivity. These effects addanother burden to an already distressed indus-try. The added costs to farmers in turn affect


markets and consumers. Ultimately the con-sumer pays a higher price for produce.

Pesticides are a useful resource for agricul-tural and industrial societies. With an increasingpopulation, food production will continue to bean important concern. If pesticides had beenavailable to kill the parasitic fungus that com-pletely wiped out the potato crop in Ireland in1845, one million people might have beensaved from starvation. When it comes to pre-venting future starvation, economic problemsdue to loss of crops, and epidemics caused bydisease-transmitting insects, pesticides serve animportant purpose.

Review


1. What are the health risks associated with the use of pesticides?

2. Why did the development of pesticides occur during a time of war?

3. According to the 1992 pesticide regulations, what must be provided to employees who han-dle harmful pesticides?

4. What are some alternatives to using pesticides?

Decisions


1. Some pesticides banned in the United States are being used in other parts of the world, espe-cially developing nations where starvation is a problem. Should there be a global ban on theuse of pesticides? Why or why not?

2. Some environmentalists and farm workers object to current regulations of pesticides becausethere is no guarantee of enforcement. How could these regulations be enforced? What penal-ties should be imposed to those who do not comply?

3. Should state and local governments be able to further restrict the use of pesticides in theirjurisdictions? Why or why not?


L imited oil supplies, highway crowding,and pollution are growing problems forthe United States and many other

nations. Many segments of society must cometogether to solve these problems, including pri-vate vehicle owners, transportation industries,and local and federal governments.

About one-third of the energy consumed inthe United States is used for transportation.Nearly three-fourths of that amount is used byautomobiles. This places a high demand onalready low supplies of oil, a nonrenewableresource. Many studies show that economicallyavailable oil supplies will dry up in about 40years, while the number of cars on the roadincreased from 50 million cars worldwide in1950 to over 400 million in 1990.

There are simple ways each person can help reduce pollution, traffic, and fossil fuel use.These include carpooling, practicing good vehi-cle maintenance, using cleaner grades of gaso-line, and using public transportation. However,long-term problems posed by automobiles stillexist. Automobiles emit toxic gases, such ascarbon monoxide, that are harmful wheninhaled. Cars also generate greenhouse gasessuch as carbon dioxide, which are thought tocontribute to global warming.

Reducing the numbers of cars on the roadwould be difficult to achieve. In the UnitedStates, social attitudes toward private vehiclesare very strong. Cars are part of the culture.Local and national organizations exist to pro-mote private vehicles as symbols of status andindependence.

The development and application of alter-natives to fossil fuels has already been provenpossible. Use of alternative energy represents amajor step toward ending U.S. reliance on for-eign fuel sources. However, powerful represen-tatives of the oil industry vigorously promote afossil fuel–based society.

Two practical solutions are the develop-ment of highly fuel-efficient or alternative-fuel vehicles, and the restructuring of publictransportation systems. In both cases, the fed-

eral government will play an important leader-ship role by providing money and enactinglegislation.

Redesigning the Automobile

“Green” technology is technology that usesrenewable, or sustainable, energy sources suchas wind and solar energy, and creates little orno pollution. These technologies are meant tobe environmentally sound while still beingprofitable. The United States government plansto spend several hundred million dollars a yearon green technology for automobiles.

The U.S. automobile industry is a strongcompetitor in the largest manufacturing indus-try in the world. The federal government isconfident that green technology in the automo-bile industry will produce greater profits and astronger hold on the global automobile market.As part of the federal government’s green tech-nology strategy, automobile executives andfederal officials will be asked to considerresearch and development in the auto industryin terms of broad social needs. The governmentplans to work jointly in a 50/50 partnershipwith the three biggest U.S. auto makers.

The U.S. automobile industry supports sev-eral other industries of economic importance,such as oil, steel, rubber, glass, and electronics.Other small businesses, such as gas stations,repair services, and automobile dealerships arealso directly connected to the auto industry.Eighteen percent of the federal government’stax support comes from the automobile indus-try and its suppliers. About 20 percent of themoney spent in the United States is directly orindirectly connected to automobiles.

Gearing Up for Mass Transit

Proponents of mass transportation think of“green,” or clean-burning cars as only a tempo-rary solution to the problems of pollution, lowoil supplies, and highway congestion. Manyexperts predict the inevitable replacement of

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should governments invest in “green” cars?


the automobile with mass transit systems. InSweden, for example, the Office of FutureStudies suggested that Stockholm should beginto reduce its emphasis on private automobilesand expand current mass transit systems.

Cities around the world will have to com-pletely restructure existing mass transportationsystems in order to make them faster and moreconvenient. For the restructuring to occur,more people would have to agree to use masstransit. More people would have to have similardestinations. Central business districts and sub-urban areas would have to expand. New, moredensely populated suburban areas would beneeded, and communities would have to be

built along major transportation routes. Loca-tions of shops and stores would need to bewithin walking or bicycle distance.

Today, public transportation systems aremore fuel-efficient than new cars, includingthose that can get 24 kilometers per liter (58miles per gallon). A study in Germanyconcluded that money spent on public trans-portation could yield as many as 33 percentmore jobs than the same amount of moneyspent on highways. But before the governmentcan invest heavily on public transportation projects, people in the United States will haveto change their relationships with their automobiles.

Review


1. Describe three reasons why green technology for automobiles is considered a worthwhileinvestment.

2. Discuss the ways that city planning will have to change in order to develop efficient masstransit systems.

3. Under what social or economic conditions do you think green cars best fill broad socialneeds? Why?

4. Under what conditions would mass transit be most beneficial? Why?

5. What are the drawbacks to developing green cars?

6. What are the drawbacks to expanding mass transit systems?

Decisions


1. What would you do with automobiles that are already on the road if alternative-fuel carsreplaced current ones? How would you deal with concerns regarding automobile insurancecompanies?

2. If you were a member of a city planning commission, what action would you take in order toease the problems of traffic congestion and air pollution in your city?

3. If you were elected to a high political office, what recommendations would you make ontransportation? Support your answer. What changes would you expect to see in local andnational economies with respect to your decision?

4. If you could only use mass transit, would it affect your concept of independence? How?


A vast amount of energy is stored in thenuclei of atoms. Devices called nuclearreactors can release this energy

through controlled chain reactions. Becausethey do not produce harmful waste chemicalsand greenhouse gases, nuclear reactors do notcontribute significantly to acid rain or globalwarming. Using nuclear energy also reducesdependence on fossil fuels from foreignsources, such as petroleum from the MiddleEast. For these reasons, many people considernuclear power the solution to the problem ofproviding safe and abundant energy.

Nuclear energy poses several problems,however. Nuclear power plant accidents canrelease large amounts of radiation into theenvironment. This happened at Chernobyl,Ukrain, in 1986. Accidents are not common,but some people think that the severe effects ofa major accident make even a small riskunwise. Another problem with nuclear energyis the radioactive waste produced by nuclearpower plants. This waste is very dangerous andwill remain so for thousands of years. Whereand how to dispose of it safely is a difficult envi-ronmental dilemma that remains unsolved.

The Disposal Problem

The options for storing radioactive wastematerials are very limited. Sinking it into theocean in special sealed containers once seemedlike a promising solution. However, bothradioactive waste and seawater are highly cor-rosive; not even the strongest containers canremain intact for the amount of time requiredto safely store wastes. Serious abuses involvingocean dumping have already occurred. Itrecently came to light that the Soviet Unionsecretly dumped dangerous reactor cores fromsubmarines into the northwestern PacificOcean. Large quantities of radioactive materialwere released. The United States and Russia areplanning a joint research program to investigatethe problem. Ocean dumping of radioactivewaste is probably not a good solution.

Burial on land poses the risk of radioactivematerials leaking out and contaminating sur-rounding soil and underground water. It is pos-sible, however, that very deep sites are usable.Another problem of land burial is that geologi-cal activity can disturb waste containers. Wastesmust be placed underground in geologicallystable areas, where earthquakes and volcanoesare unlikely to occur. Because there is somedegree of geological activity everywhere onEarth, however, underground burial anywherecarries a risk.

In 1986, the U.S. Congress authorized theDepartment of Energy (DOE) to search forplaces to bury more than 22,000 tons of highlyradioactive spent nuclear fuel rods from powerplants. Temporary storage space for the usedrods is nearly full, and a permanent repositorymust be found soon.

Communities near proposed waste sitesprotested the construction of the sites. Congresseventually decided on a site under YuccaMountain in the southern desert of Nevada.The proposed repository would be locatedunderneath a thick layer of volcanic ash; itwould lie well above groundwater level toreduce the danger of seepage.

The DOE is now conducting studies of thissite. Large numbers of samples of core materialsare being collected and tested. About $6 billionis expected to be spent on remaining studies.Before Yucca Mountain can be used as a dis-posal site, it must be determined that the site isboth geologically stable and safe from intrusionby groundwater.

A number of geologists have warned thatthe area around Yucca Mountain is geologicallyactive, with numerous faults and even a smallvolcano nearby. If earthquakes or volcaniceruptions occurred with sufficient violence, theradioactive material at the site could be carriedto the surface, threatening the entire region.Other geologists argue that the volcanic activitynear Yucca Mountain is mild, with a minimalchance of a large eruption, and that the chanceof a severe earthquake is also remote.

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nuclear waste disposal: where and how?


Studies of the patterns of mineral depositsuggest that there may be periodic upwelling ofgroundwater at the Yucca Mountain site. Suchupwelling could carry radioactive waste to thesurface or wash it into aquifers. DOE officialsclaim, however, that the likelihood of suchevents occurring in the next 10,000 years—theperiod of greatest danger—is extremely small.Some geologists think that the rock formationsin question were formed by rainwater seepingdownward, not by groundwater seepingupward.

The scientists who oppose development ofthe site accuse the DOE of failing to conduct anunbiased scientific study. They claim that theDOE’s obvious support for the project is basedon political choice rather than objective scien-tific evidence. The evidence presented so far bythe DOE appears to its opponents to have beengathered mainly to ward off legal challenges.Opposing scientists argue that the decision to goahead with development is far too important tobe left to a government agency they think isbiased. The DOE, in turn, accuses the scientistsof being biased against the repository.

The DOE also has plans to open an under-ground repository for radioactive waste in NewMexico. The planned facility is called the WasteIsolation Pilot Plant (WIPP). It consists of a largenumber of caverns cut out of a deep saltdeposit. The DOE had planned to store nearly200,000 drums of high-level radioactive wasteat the site and test for any resulting contamina-tion. However, opposition from the State ofNew Mexico caused the DOE to change itsplans. The agency now plans to carry out thetests aboveground.

Radioactive waste must be disposed ofsomehow. A tremendous amount of waste hasbeen generated, and more will be produced inthe future. Scientists generally agree that burialis the best disposal method. But is Yucca Moun-tain the best site? Is it geologically stable andsafe from the intrusion of groundwater? No oneknows for sure. Geologists cannot predict how aregion will change over many thousands ofyears. Waste will be deposited, however, atYucca Mountain or at a place like it. Onlyfuture generations will know if this generationchose wisely.

Review


1. What are the unique disposal problems of nuclear waste?

2. Why is ocean dumping generally thought to be a poorer choice than land burial?

3. Summarize the arguments in favor of Yucca Mountain as a nuclear waste burial site.

4. Summarize the arguments against the Yucca Mountain site.

5. Explain what WIPP is, and describe the controversy surrounding it.

Decisions


1. Who do you think should decide where a radioactive waste repository should go?

2. How would you feel about a proposed nuclear power plant or repository that was going to besited hundreds of miles from your home? How would you feel if you lived only a few milesaway? Should you still be concerned, even if you lived far from the site?

3. Should the repository at Yucca Mountain be built? Why or why not?


S oil is one of Earth’s most importantresources. The upper layer of soil, or top-soil, is richest in humus, and is the most

fertile layer. Topsoil provides the best mediumfor the growth of plants, including importantfarm crops.

About 1.8 billion metric tons of topsoil arelost each year in the United States due to ero-sion by wind and moving water. Some U.S.farmers have been hard-hit by falling grain andvegetable prices. As a result, these farmers havetried to offset the economic setback by clearingmore land for farming and by farming moreintensively. The result has been an even greaterdepletion of topsoil.

Much of the best U.S. farmland is located inrelatively dry areas, increasing the need formore extensive irrigation of additional crops.Crop irrigation, however, is one of the mostserious causes of erosion throughout the UnitedStates. Erosion can occur at the staggering rateof 2.5 metric tons of soil per hour of wateringfor each hectare of land.

The cheapest and most popular method ofirrigation involves the use of furrows, or ditches,that run between rows of plants. Water releasedinto the furrows seeps into the soil; as the watertravels down the furrows, it collects topsoil withthe force of its motion. Most of the soil is ulti-mately washed into natural waterways, togetherwith dangerous pesticides and fertilizers.

The problem does not end there. Fine clayparticles carried in the water settle to the bot-tom. As the clay settles, it seals the pores in thesoil, preventing water from reaching the rootsof plants. In this way, irrigation loses its effec-tiveness as time passes. The soil’s ability toabsorb water can decrease rapidly within justweeks.

PAMs to the Rescue

A possible solution to the problem of irriga-tion-related erosion was developed by RobertSojka of the Agricultural Research Association,assisted by Isaac Shainberg, an Israeli research

scientist. These scientists found that chemicalsknown as PAMs (polyacrylamides), added toirrigation water, limit erosion and prevent soilfrom becoming sealed by sediments. PAMs arevery large molecules that can develop a nega-tive electric charge. They are drawn to andattach to the edges of tiny clay particles, whichtypically have a positive charge. PAMs causethe particles to hold together and resist theforce of moving water.

Adding PAMs to the soil can greatly reducerates of erosion and soil clogging. The additionof only ten parts per million of PAMs to waterearly in the irrigation process can reduce ero-sion by as much as 99 percent. The cost isapproximately $7.40 per hectare per day ofirrigation. Small amounts of PAMs added laterin the watering process provide continuing pro-tection. PAMs have such low toxicity that theypresent no real pollution threat.

PAMs are particularly useful on land thatslopes sharply. Since water traveling quicklydown a slope removes more topsoil than watermoving across a flat field, irrigation efforts onslopes are often inefficient. According to oneestimate, the use of PAMs on sloping fieldscould greatly increase crop yields, producing ayield that is equivalent to farming one to twoextra hectares of land.

Problems with PAMs

There are drawbacks to the use of PAMs.First, they must be applied in the properamounts, which requires extra time and care.Second, PAMs are not effective when added toirrigation water that is already dirty. PAM mole-cules cause the suspended soil sediments indirty water to stick together, which clogs irriga-tion furrows. Clean water must therefore beused, which may not be readily available.Third, the cost of PAM application may seemlow, but may not prove to be cost-effective,especially in dry areas.

To an extent, this negative economic effectcould be offset by the expected increases in crop

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pams and soil erosion control: are syntheticmethods the remedy?


yields resulting from more efficient irrigation.The most incalculable saving that could resultfrom the use of PAMs, however, is the preven-

tion of topsoil erosion and the protection of thenation’s farmland.

Review


1. Explain why soil erosion is a serious problem.

2. Describe the problems related to the use of furrows to irrigate farmland.

3. What are PAMs and how do they help prevent soil erosion?

4. What are the short-term and long-term advantages of using PAMs?

5. What are the short-term and long-term disadvantages of using PAMs?

Decisions


1. Suppose you were a farmer with limited financial resources concerned with increasing yourprofits. What factors would affect your decisions on farming and irrigation practices? What,if anything, would you do to reduce erosion?

2. If you were elected to a powerful government position overseeing agricultural practices, whatrecommendations would you make concerning soil erosion? How could you balance theneed to take measures against soil erosion with the economic hardships your recommenda-tion might cause small-scale farmers?

3. Soil erosion is a global problem related to human population growth and the challenge ofobtaining sufficient resources for survival. In some parts of the world, erosion contributes tofood shortages and famine. What would you suggest to help solve this worldwide problem?


T he disposal of toxic wastes presentsmany serious problems. Sanitary land-fills used for the disposal of ordinary

garbage are generally inadequate for toxicwastes. For a site to be appropriate for toxicwastes, it must present a minimal chance ofleakage. Sites chosen must contain underlyingrock that will prevent leaching or upwelling ofwastes. It is extremely important to select siteswisely, because leakage of toxic wastes canresult in large-scale poisoning, increased cancerrates, and other harmful effects. Even whentoxic-waste disposal sites are chosen with theutmost care, absolute safety is difficult toassure, especially over the long term.

There are other factors involved in choosingsites besides safety. There are aesthetic and psy-chological considerations, because landfills canmake areas unattractive and undesirable to livein. Important social, economic, and politicalissues are involved in siting decisions as well.The construction and operation of a site cancreate job opportunities that are attractive toresidents of low-income areas. Residents ofmore affluent areas, on the other hand, haveno reason for wanting toxic-waste facilities neartheir homes. These residents band together,using their money and political influence toprevent landfill projects from materializing intheir areas.

A Proposed Toxic-Waste Site in Mississippi

Noxubee County, in eastern Mississippi (asshown on the map), is one of the lowestincome counties in the nation. A large portionof its residents—about 70 percent—are AfricanAmerican. Two large companies recentlydecided to seek a permit to construct ahazardous-waste facility in Noxubee County,even though the state allows only one suchfacility in a county. The two companies gotaround this limitation by joining forces. Theynow hope to construct one of the largest toxic-waste dumps in the southern United States, one

that would handle about 180,000 metric tons ofmaterial each year. The companies defend theirplan on the basis of the local geology. Theyclaim that a thick layer of underlying chalk inthe area of the dump site would prevent toxicwastes from leaching into the environment.

The leadership of the NAACP (NationalAssociation for the Advancement of ColoredPeople) supports the plan. They believe thehealth risks would be minimal and new jobswould be created for the local low-income pop-ulation. The waste-management companieshave promised to hire minority-owned firms tohelp operate the facility, which could then gen-erate many new small businesses. The NAACPleadership claims that most of the residents ofthe area support the plan.

Charges of Exploitation

There is great division within NoxubeeCounty over the plan. Most local middle-classCaucasian and African-American residents,who would not benefit from the creation ofnew jobs, oppose the plan. These residentsrefute the NAACP claim that most residentssupport the plan. They cite statistics suggesting

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toxic wastes in Noxubee County: Economic Opportunity or exploitation?

Brooksville

Macon

Shuqualak

Alabama

Ark.

Jackson

Mississippi

Mississippi river

Gulf of Mexico

Louisiana

Noxubee

20

55

59

20


that in local elections, most people voted forcandidates who were opposed to the plan.

Opponents also argue that the site of thetoxic-waste facility was not chosen on the basisof geology, but rather on the basis of demo-graphics. The geology of Noxubee County, theysay, is not significantly different from that of anumber of other counties in eastern Mississippi.They believe the siting decision was based onthe racist assumption that African Americansare desperate enough to opt for job creation atthe expense of their own long-term well-being.

A Worldwide Problem

The connection among environmental pollu-tion, race, and economics has come into focusrecently in other places around the world. Forexample, in a 1991 memo, the high-rankingchief economist of the World Bank claimed thatpoorer countries are “underpolluted,” and thathighly polluting industries should be locatedthere. The author argued that residents of suchcountries face great health risks in any case,given their impoverishment and poor living con-ditions. He also claimed that, for these residents,

the economic benefits of the establishment ofnew industries would outweigh the risks.

The memo created an uproar and waswidely attacked as being racist. Some peoplestill defended the idea of promoting the growthof “dirty” industries in poor areas, in spite ofresistance to such industries by those living inaffluent regions. The possible economic benefitscould outweigh the disadvantages.

Making a Decision

The U.S. Environmental Protection Agen-cy’s Office of Civil Rights is currently investigat-ing the situation in Noxubee County. Thisinvestigation was prompted by local environ-mentalists and various spokespersons for theAfrican-American community in Noxubee. Theorganization will have to decide whether racialdiscrimination was involved in the site choice.They will also need to consider whether themostly minority population would face exces-sive and unfair risk from the construction of thetoxic-waste facility. If the answer to these ques-tions is “yes,” then the plan could be prohibitedas a violation of the Civil Rights Act of 1964.

Review


1. What dangers are associated with the disposal of toxic wastes?

2. Summarize the arguments in favor of locating toxic-waste facilities in low-income areas.

3. Summarize the arguments against locating toxic-waste facilities in low-income areas.

4. How does the issue of race relate to controversies over site selection of environmentally dangerous facilities?

Decisions


1. Suppose you were an unemployed resident of a town for which a toxic-waste facility hasbeen proposed. What factors would you evaluate regarding the soundness or desirability ofthe plan? How do you think you would feel about such a plan?

2. How much importance do you think should be given to demographics in deciding the loca-tions of toxic-waste facilities? How would you feel if it could be proven that a disposal com-pany had considered the racial or economic makeup of a community in its decision-makingprocess?

3. People with low incomes may be more willing to accept the potentially dangerous environ-mental conditions created by “dirty” industries providing there are economic advantages forthem. Do you think it is fair, therefore, to locate potentially dangerous facilities in theirneighborhoods? Explain your answer.


T he disposal of sewage is an increasinglyserious problem in many parts of theworld. To help solve the problem of

sludge disposal, a number of coastal cities havebegun dumping sludge from sewage plants off-shore. At offshore sites, dumping vessels releasesewage close to the water’s surface. Althoughmost sludge sinks to the bottom, many of thesmaller particles will drift long distances beforesettling. For example, small sludge particlesdumped off the coast of New Jersey may drift as far as the waters off North Carolina beforesinking to the bottom.

Some oceanographers think they havecome up with better ways to dump sludge. Onehas suggested “rocketing” the sludge to thedeep-sea bottom by placing it in large drums,attaching them together, and placing a massivenose cone on the bottom drum. The chain ofdrums is released at the surface and is pulledrapidly downward by the nose cone. Eventuallythe cone would implant itself deeply into theooze that covers the sea floor.

A group of oceanographers from Denmarkhas suggested ocean disposal of sludge throughan enormously long hose. The hose would belowered from a dumping vessel to the deep-seabottom. It would be one-half meter in diameterand would have a nozzle weighing many metrictons to ensure that it sinks rapidly. Sludge couldbe released directly to the bottom, where itwould settle many kilometers below the surface.

Another method of deep-sea dumping pro-poses the use of a type of elevator that wouldbe lowered between two ships to transport thesludge downward.

A Solution to Land Pollution?

All these methods of deep-sea dumpinghave one benefit in common. They provide forcontrolled flow of sewage directly to the seafloor. There would be little or no direct contam-ination of shallower levels of the ocean. Theproblem of large-scale particle drift wouldthereby be nearly eliminated.

These methods also have something else incommon; only a few years ago, they wouldhave been virtually unthinkable. At that time,nearly all reputable oceanographers and envi-ronmentalists would have argued stronglyagainst deep-sea sewage disposal. It would havebeen simply unacceptable to consider using theocean as a dumping ground. However, in thelast few years, the problem of where to putsewage has grown more urgent. Proposals thatonce would have been considered far too riskyare now considered justifiable. The alternative,of course, is the use of limited land space fordisposal, creating more pollution on land.

The oceanographers in favor of the plans fordeep-sea dumping point out that the total areaof deep-sea bottom is enormous, covering morethan 50 percent of Earth’s surface. The possibil-ity of running out of places to dump sewagewould therefore be extremely remote. Also, theyclaim that there would be little risk of dangerouscontamination of higher levels of the ocean. The action of currents usually does not lift updeposited materials from that far underwater.

Scientists in favor of the plans also pointout that there are not very many life forms onthe deep ocean floor. Therefore, relatively feworganisms would be affected by the sludge.Also, the types of organisms that live at thatdepth are not a major part of the food chains athigher ocean levels. Thus, there would be littlerisk of contamination of shallow-water species.Because almost all species of seafood that areharvested live in the upper levels of the sea, the health risk to people who eat seafoodwould be small.

An environmental benefit of sludge dump-ing has been suggested. Some scientists thinkthat sludge, a rich mix of organic and mineralcompounds, might act as a powerful fertilizerfor ocean life forms. It may thereby increase thepopulation sizes of ocean species rather thandecrease them.

Just Another Kind of Pollution?

There is another side to the issue of deep-

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super trash bin or environmental trash pit?


sea dumping. No direct large-scale dumping hasactually been carried out on the deep-sea floor,so its consequences are unknown. Environmen-talists highly concerned about deep-sea dump-ing point out that oxygen would be consumedas organic matter in sludge breaks down. Thedecrease in oxygen could lead to possible wide-spread suffocation of ocean organisms thatdepend on the oxygen supply.

Sludge often contains highly toxic materials,including heavy metals. The effects of thesematerials on deep-dwelling organisms cannotbe ignored. Nor, the scientists claim, shouldsuch organisms be considered unimportant. Theweb of interactions among Earth’s life forms isso complex that it is not possible to predict withcertainty the ultimate effects of deep-sea dump-ing on ecosystems throughout the world.

Critics argue that it is unsound to allowdeep-sea dumping when its effects may not berecognized in time to prevent disaster. They alsocite with pride many of the advances that havebeen made in recent decades against the spreadof pollutants. Many of these advancements result

from increased awareness of how pollution prob-lems occur. Deep-sea dumping would, in theopinion of many environmental advocates, rep-resent a setback. They also point out that oceandumping of sludge in any form is now illegal inmany regions. Critics of deep-sea dumping seeno reason to repeal essential protective legisla-tion that has been very difficult to put in place.

A Proposed Pilot Plan

Oceanographers met at Woods HoleOceanographic Institution in Cape Cod, Massa-chusetts, and proposed a plan to begin deep-seadumping and to study its effects. According toproponents of the plan, about 1 million metrictons of sludge would be deposited each year for10 years. The United States government wouldoversee the pilot program, at the end of whichthe effects of the dumping would be studied. Atthat point, a decision would be made as towhether to increase the yearly volume ofsludge disposed of in this manner, or to discon-tinue the practice of deep-sea dumping.

Review


1. Describe the main features of the newly proposed methods of deep-sea sewage disposal.

2. What general advantage do these methods have over land disposal?

3. Summarize the arguments that deep-sea sewage disposal is ecologically safe.

4. Summarize the arguments against deep-sea sewage disposal.

Decisions


1. Do you think that carrying out a 10-year pilot program of deep-sea sewage dumping is agood idea? Evaluate the argument that such a period is too short to allow proper assessmentof the effects.

2. On the basis of the arguments cited in the reading, would you be in favor of deep-sea sewagedumping? Explain your answer.

3. Suppose you lived in an area where sludge was dumped on land. How might the disposal ofsewage near your home affect your opinion on the advisability of deep-sea dumping?

4. Do you think it is a good idea to repeal current regulations forbidding ocean dumping inorder to test the possibility of deep-sea dumping? Explain your answer.

5. Suggest another possible approach to the problem of sewage disposal that you think might beworkable but less damaging to the environment. What are some drawbacks to the approachyou have suggested?


E arth, the water planet, contains 1.4 bil-lion cubic kilometers of water. Thatamount represents 3.8 trillion liters of

water for every person on Earth. Why, then, doso many experts worry about whether therewill be enough water to sustain the humanpopulation? Ninety-seven percent of Earth’swater is salt water. Of the remaining 3 percentthat is fresh, more than 2 percent is frozen inpolar ice. That means less than 1 percent ofEarth’s water is available to sustain life. Morethan 90 percent of available fresh water onEarth runs in river basins. More than 200 riverson the planet are shared by two or morenations, and almost half of the world’s humanpopulation depends on water originating in aforeign country.

Although competition for water rights occursin developed countries such as the United States,most struggles over water occur in developingcountries. Rapidly growing human populationsand the pressing need for industrial developmentoften lead developing countries to undertakelarge-scale water projects. Many of these pro-jects, although initially helpful, can hurt the verypeople they were supposed to help.

Building High Dams

Many developing countries try to controltheir region’s water supply by building enor-mous high dams. These dams, generally morethan 150 meters tall, divert the normal flow ofriver water. High dams use moving water as apower source. They often contain hydroelectricplants that supply electricity for homes andindustries. The stability of developing countriesdepends on the availability of electric power torapidly growing industries and urban centers.

When a river is dammed, a lake or reservoiris created behind the dam where river waterbacks up. This stored water can serve as a watersupply for drinking and for crop irrigation.Often, industries that use large amounts ofwater, such as the paper industry, are importantto the economies of developing countries.

Relocating People

High dams, which are built on major rivers,form enormous reservoirs that fill hundreds ofsquare kilometers of land. The people who liveon this land are resettled while the dam is beingbuilt. The land around the dam and the areas itirrigates increase in value. As land values sky-rocket in developing countries, poor farmers areoften bought out by rich individuals or by cor-porations. These farmers must then relocate,adding more displaced poor people to the num-ber who lost their homes prior to the dam’sconstruction.

The Manatali Dam on the Senegal River inAfrica caused the relocation of about 180,000people. Some were forced out by land investors,others by the flooding of their homeland. InIndia, the Narmada River Project—which whencompleted will include 30 major dams, 125mid-sized dams, and 3000 small dams—willflood 388 square kilometers of land, forcing theresettlement of 100,000 to 1 million people.Most of these people are poor.

The James Bay Project, planned for northernQuebec, Canada, would flood the ancestral landsof the 10,000 native Cree who have treaty rightsto the land. If completed, this vast hydroelectricproject would devastate wetland habitats formigrating and breeding birds and the fish andwildlife upon which the Cree depend. Most ofthe electricity the dam will produce is expectedto be sold in the northeastern United States.

Massive Debts and salty soil

High-dam construction costs millions ofdollars. To pay for the dams, developing coun-tries must take out huge loans from lendinginstitutions such as the World Bank. Manydeveloping countries incur huge debts.Guatemala found itself deep in debt when itbuilt the Chixoy Dam. Today, 40 percent ofGuatemala’s international debt payments go topay off this loan. Guatemala’s creditors, theInter-American Development Bank and theWorld Bank, suggested that Guatemala fund its

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are large-scale water-diversion projects the answerfor a thirsty world?


debt by imposing a 70 percent increase in thecost of electricity to its citizens. This suggestionwas not received favorably by the public.

Supporters of high dams argue that usingreservoir water to irrigate crops will producehigher yields. The irrigation is usually beneficialto farmers in the short run. Long-term conse-quences of irrigation, however, can becatastrophic. Irrigation water, unlike naturalrain water, may contain a good deal of dissolvedsalt. As the irrigation water evaporates fromcropland soil, a residue of salt is left behind.Over time, the soil may become too salty tosupport plant life. Studies indicate that suchsalinization of soil has already resulted in a 24percent loss of irrigated cropland worldwide.

There are some irrigation systems that limitthe effects of salinization, but these systems arecostly and require specialized planning andmanagement. Developing countries are so con-cerned with the construction of high dams forindustrial development that they do not plansufficiently for quality irrigation. Irrigation pro-jects are often added as an afterthought whenthe dam has been completed. By this time, thenation may be so burdened with debt, it cannotafford the necessary irrigation technology thatwould be less destructive to cropland.

Other Environmental Effects

The flooding of the land surrounding a dammay cause vegetation to rot and fish to die. Thewater can also become a breeding ground fordisease-carrying insects that require still watersto thrive. As a result, local populations maysuffer more frequently from diseases such asriver blindness and guinea worm.

In some ways, high dams actually increasethe demand for water, not satisfy it. Industryhas used about 10 percent of available water inmost developing countries. As dams are builtand hydroelectric power becomes more avail-able, industrial water use is expected to jump350 percent by the end of the century.Increased industrialization will lead to increasedindustrial pollution. Yet industrialization maynot bring the prosperity these countries hopedfor. Some multinational corporations are relo-cating their more polluting processing plants todeveloping countries. In such countries, theycan use cheap water, electricity, and labor, andavoid the costs and constraints of environmen-tal regulations in developed countries. Most of

the corporations take their profits out of thehost country, leaving the host country poor andenvironmentally damaged.

Water Wars

Water is essential to life, but is available inincreasingly short supply in many places in theworld. Some social scientists predict that con-flicts over water rights will be the cause of somewars in the future. Water conflicts are alreadyoccurring in some places, and are especiallyfierce in the arid Middle Eastern regions.

The Nile River in Africa provides water toeight countries, which compete aggressively forit. The economies of these nations dependsupon the Nile water. For example, more than90 percent of Egypt is desert. Egypt reliesalmost entirely on the Nile for water, yet 86percent of the Nile water Egypt uses originatesin Ethiopia. Egypt built the Aswan High Dam in1970 to generate electricity and irrigate moreland. The silty waters of the Nile are building upbehind the dam and will eventually destroy it.In the meantime, the nutrient-rich silt has beenblocked from moving downstream, as it other-wise would, to the Nile delta. This once-fertilecropland is becoming barren for lack of theannual deposition of Nile silt.

Egypt is planning another water project,which is likely to lead to serious conflicts withsome of its neighbors. It will move more waterthrough the Nile Basin by creating a bypass tochannel Nile water away from the vast Suddwetlands in central Sudan. The wetlands are arich oasis for wildlife in that arid region. Theplanned bypass would rob the wetlands ofwater and deprive the people of Sudan of wateras well. The lengthy civil war in Sudan wascaused in part by this loss of water to parts ofthat nation.

Turkey’s recently completed Ataturk Damdiverts nearly one-third of the water that for-merly flowed into Syria and Iraq. The AtaturkDam is a part of Turkey’s planned Anatolia Pro-ject, which would prevent virtually all thewaters in the ancient Euphrates and Tigrisrivers from flowing into Syria and Iraq. Thesetwo nations are alarmed; they cannot survivewithout water from these two rivers. All threenations are trying to negotiate an agreement toallocate the river water they all desperately need.

Reaching Agreement

A way must be found to enforce equal dis-tribution of the world’s freshwater supplies. Astep in that direction was taken in 1988 in SanFrancisco, California. At a conference on waterrights sponsored by the International RiversNetwork, 26 nations signed the San FranciscoDeclaration. Although the Declaration receivedwidespread support, it is not binding or enforce-able as international law. The document pro-vides for the following conditions that must bemet before any nation undertakes a large-scalewater project: (1) free availability of informationabout the project; (2) respect for human rightsby seeking alternatives to huge water projectsthat displace many people; (3) thorough long-term economic analysis prior to the project; (4)comprehensive environmental and health

assessments prior to the project; (5) demonstra-tion that public health will be improved by theproject; and (6) clear information about whatland is to be irrigated, how it will be irrigated,and the environmental effects of irrigation.

Some countries are working together tosolve their water problems. For example, riversthat flow from northern Mexico into the UnitedStates contain human and industrial wastes.The pollution is creating serious problems inMexico and along San Diego’s coast. Ecoparque,a combined park and sewage-treatment centerin Tijuana, Mexico, was jointly built by groupsin both countries. It treats the Tijuana River’ssewage-laden water and then uses the treatedwater on trees and plants in Ecoparque. Mexicogets sewage treatment and a park, the UnitedStates gets a clear-flowing and nonpollutingriver from Mexico.


Review


1. Why do developing nations favor the construction of high dams?

2. Why must large numbers of people usually be relocated prior to the construction of a dam?

3. How has the diversion of reservoir water for irrigation proved to be harmful for farming?

4. What other obstacles prevent high dams from fully benefiting developing nations?

Decisions


1. The Glen Canyon Dam has greatly reduced the flow of the mighty Colorado River. The damprovides electricity for Las Vegas and other cities. When electricity demand is high, hugequantities of water are released from the reservoir all at once. The daily water surge is ruin-ing campsite beaches and wildlife habitats in the Grand Canyon, through which the riverpasses. Who do you think has the greater right to control the water flow: people in the citieswho need the electricity or people concerned about the Grand Canyon environment? Howwould you resolve this conflict?

2. Every nation has given itself the right of “eminent domain,” which is the ability to buy outcitizens whose residences are in the way of public-works projects. For example, if your houseis in the way of a projected interstate highway, the government has the right to compensateyou for it and force you to vacate. Do you agree with the principle of eminent domain? Whatcould happen if nations no longer had this right?

3. How might developing countries be discouraged from carrying out large-scale water projectsthat would be harmful to them in the long run? Who should be responsible for promotingalternatives in these countries?


E very year, about 3.2 million metric tons ofoil pour into the world’s oceans. About 50percent seeps into the sea from natural

offshore deposits. Another 30 percent comesfrom inland oil spillage that travels via rivers intothe oceans. Twenty percent of the oil in the seascomes from oil well blowouts, pipeline breaks,and oil tanker spills. There are between 5000and 10,000 oil spills in U.S. waters annually.

The overall long-term effects of oil on themarine environment are not known. However,depending on winds and ocean currents, theshort-term effects of oil spills can be catastrophicfor marine life. Coastal ecosystems may takefrom two to ten years to recover from the effectsof oil spills. Scientists are therefore seeking anefficient and inexpensive way to clean up oilspills.

A Burning Question

In August 1993, more than 98,000 liters ofAlberta crude oil leaked slowly into the watersoff the Grand Banks in Newfoundland. Twohundred scientists stood and watched, curiousbut unconcerned. The spill, after all, was not anaccident. It was part of the Newfoundland Off-shore Burn Experiment (NOBE), intended totest the effectiveness of burning as a method ofcleaning up oil spills. For three hours, the scien-tists watched flames shoot more than 90 meters(m) into the air and smoke plumes reach 1200m high. The $6.5 million project would helpdetermine if burning is the low-cost, environ-mentally safe method of oil cleanup many peo-ple believe it is.

Two burn tests were conducted. The firstwent according to plan. During the second,technicians experienced problems with theboom, the fireproof enclosure used to “roundup” surface oil. Technicians position the boomsprior to setting the oil ablaze. Midway throughthe second burn, the boom, 200 meters indiameter, began to fall apart. Scientists stoppedthe burn immediately and prevented the oilfrom escaping.

The failure of this test did not alter the sci-entists’ belief in the efficiency of burning oil.They admitted, however, that boom design andtechnology needed improvement. Proponentsof oil burning point out that with improvedboom design, the method will prove to be moreefficient and economical than mechanicalmethods of oil removal currently used.

Scientists acknowledge that burning is notsuitable for all oil spills in all conditions. Highwinds in excess of 20 knots and short, choppywaves higher than 1 meter may make burningimpossible. Such conditions are common in theopen ocean, especially in northern seas. How-ever, in situations where conditions are favor-able, burning can remove as much oil in oneday as mechanical skimmers and other devicescan remove in one month.

Oil burning has its critics. They point outthat many kinds of oil mix with water quitereadily. The more water that is mixed with theoil, the harder it is to burn. Once an oil slickcontains 60 percent water, burning is impossi-ble. Furthermore, burning of oil slicks that areblown or washed into coastal areas with abun-dant wildlife or near human population centerswill endanger life. Some studies also show thatburning does not completely dissipate surfaceoil. An oil slick must be at least 2 to 3 millime-ters (mm) thick before it will ignite—that iswhy booms are used to “pile up” surface oil.Still, the 1 mm of oil that slicks the surface ofthe water cannot be burned off.

Concerns also center around air pollutionfrom smoke plumes. During a study of 1000chemicals produced by burning oil, scientistsfound that rather than staying within the smokeplume, toxic chemicals dispersed in all direc-tions, especially downwind. Thus, the toxic sootfrom burning oil may settle on beaches and pop-ulated areas. Citizens, particularly those wholive near coasts, are understandably worriedabout the health effects of these airborne toxins.

Proponents of burning, however, claim thatthe overall concentration of air pollutantsresulting from burning an oil slick is the same

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is burning the best way to clean up oil spills?

as that expected from evaporation alone. Somescientists say that burning even reduces con-centrations of air pollutants by between 5 and75 percent. They also claim that smoke fromburning oil disperses quickly, leaving little evi-dence of deposition farther than half a milefrom the burn. Under optimal conditions, thiscleanup method may remove 99 percent ofspilled oil. Wildlife officials discount damage toanimals; they “found no evidence of curiousanimals that were drawn to investigate the oilyinferno.”

Oil Eaters

Techniques of bioremediation (BY-oh-ree-mee-dee-AY-shun) are also being used for oilspill cleanups. In bioremediation, oil-eatingbacteria or algae are applied to the spill. Theresults have been mixed. In 1989, the oiltanker Exxon Valdez spilled 42 million liters ofcrude oil into Alaska’s Prince William Sound.Exxon, the owner of the tanker, applied fertil-izer solutions to the spill to stimulate the

appetites of oil-eating organisms. Exxon engi-neers claimed that the application of 48,000kilograms of nitrogen fertilizers acceleratedmicrobial consumption of oil three- to five-fold. Three years after fertilizer application, theU.S. Environmental Protection Agency’s Sci-ence Advisory Agency stated that Exxon’sreported success with bioremediation wasexaggerated and their data misleading. EPAscientists question whether it wasn’t the fertil-izer but the high-pressure wands used to applythe fertilizer that actually accounted for mostof the cleansing.

EPA conducted its own tests on threeislands in Prince William Sound. Test resultsindicated that the most effective fertilizer accel-erated microbial degradation of oil by “abouttwo summers.” As one EPA scientistcommented, “The data didn’t indicate thatbioremediation was such a great idea, but wedidn’t think it would do a lot of harm either.”Though not the remedy Exxon claims, bioreme-diation could be beneficial in increasing the rateat which oil is biodegraded.

Review


1. What are three reasons why burning may be the best means of cleaning up oil spills?

2. What are three reasons cited for opposition to burning oil spills?

3. How are microbes used to clean oil spills?

Decisions


1. A large percentage of Americans live within 80 kilometers of a coast. If you lived near or on acoast, would you support or oppose a policy of burning oil spills? Why?

2. If it were shown that burning is a promising method of oil-spill cleanup, would you supportdeliberate test spills in the ocean to confirm this? Why or why not? Do you agree with theEPA’s refusal to issue permits for test spills in the ocean? Explain your answer.

3. Based on what you have read, do you think burning or bioremediation is the least environ-mentally damaging method of cleaning up oil spills? Explain your answer.



W hen lightning bolts or ultravioletlight from the sun strike moleculesof oxygen (O2) in the upper atmos-

phere, the oxygen atoms split and free oxygen(O) results. Some of this free oxygen binds toother oxygen molecules, forming ozone (O3).The layer of ozone in the stratosphere—20 to50 kilometers above Earth—screens out morethan 99 percent of the sun’s harmful UV radia-tion. Nitrous oxides, produced by volcanoes,can break down atmospheric ozone. Through-out Earth’s history, the rate of ozone formationand ozone breakdown by natural events havebeen in balance—until now.

In the early 1970s, atmospheric scientistsdiscovered a large area of significant thinning inthe ozone layer over Antarctica. This is com-monly referred to as the ozone hole. Theirresearch led them to conclude that human-made substances called chlorofluorocarbons(CFCs) were entering the stratosphere anddestroying the protective ozone layer. CFCs areorganic compounds containing hydrogen, car-bon, chlorine, and fluorine. They are used ascoolants in refrigerators and air conditioners, tomake plastics such as styrofoam, and to cleancomputer silicon chips and circuit boards.

Because any alteration of Earth’s atmos-phere could have disastrous environmentaleffects, scientists called for an immediate halt tothe manufacture and use of CFCs. In 1987, 24nations signed the Montreal Protocol, a plan toreduce CFC production by 35 percent by theyear 2000. By 1990, 49 countries had signedthe treaty, and a provision to ban CFC produc-tion after the year 2000 was put in place.

Effects of Ozone Depletion

Exposure to UV radiation can cause deadlyskin cancers in humans. The U.S. Environmen-tal Protection Agency (EPA) reported that forevery 1 percent decline in atmospheric ozone,there would be a 1.3 percent increase in theamount of UV radiation bombarding Earth’ssurface. By the year 2000, when ozone deple-

tion could be most severe, the EPA projects a 6 percent loss of ozone cover in temperate climates, resulting in an 8 percent increase inUV radiation. In the United States, this couldresult in an additional 940,000 cases of non-lethal skin cancer and 30,000 cases of fatal skincancer each year.

The EPA further anticipates that higher lev-els of UV radiation hitting Earth will negativelyaffect plant life, including crops. Research hasshown that intense UV radiation is fatal toplants; even small increases in UV exposurecause a reduction in photosynthesis, stuntedgrowth, and mutations. The United NationsEnvironment Programme reported thatincreased UV radiation could severely disrupt oreven destroy the world’s ecosystems by killingoff large populations of plants, which form thebase of food chains.

Natural Causes of OzoneDepletion?

A recently published book, Trashing thePlanet, by Dixy Lee Ray, zoologist and formerWashington governor, criticizes alarmist predic-tions about the ozone layer. Much of her datawere obtained from the book Holes in the OzoneScare: The Scientific Evidence that the Sky Isn’tFalling, by Ralf Schauerhammer and RogelioMaduro. She also cites Fred Singer, former chiefscientist for the U.S. Department of Transporta-tion. These books present data that seem tocontradict scientific arguments that ozonedepletion is caused by human-made CFCs. Thebooks have been followed by magazine andnewspaper articles condemning the scientificcommunity for falsely raising alarms about anonexistent threat to the planet’s atmosphere.These writers insist that the ozone layer is notbeing unnaturally depleted. They claim that anyozone depletion that is occurring is caused bynatural events.

Maduro and Schauerhammer contend thatthe chlorine that destroys atmospheric ozonecomes from natural sources: 540 million metric

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is ozone depletion a serious problem?


tons from the oceans, 33 million metric tonsfrom volcanoes, 7.6 million metric tons fromburning of biomass, and 4.5 million metric tonsfrom marine organisms. By contrast, CFCs con-tribute only 680,000 metric tons of chlorine tothe atmosphere; they cannot, therefore, be thecause of stratospheric ozone depletion.

Atmospheric scientists dispute these figures.They point out that chlorine from naturalsources is soluble in water; therefore, it iswashed out of the lower atmosphere by rainbefore it can reach the stratosphere where itdamages ozone. CFCs, on the other hand, areinsoluble in water and can reach the stratos-phere, where they release chlorine. Further,chemical analyses of stratospheric chlorine failto support critics’ claims. First of all, if sea salt,which contains chlorine, reached the stratos-phere, it would leave a trail of chlorine in thelower atmosphere. There is no such trail.

Burning biomass creates a distinctive typeof chlorine, a compound that containsmethylchloride. Maduro asserts that the stratos-phere holds 7.6 million metric tons of chlorinecontaining methylchloride. Yet, satellite dataconfirm that only 20 percent of the chlorinecompounds in the stratosphere containsmethylchloride. Only one-quarter of thisamount, or 5 percent of the total chlorine in thestratosphere, can be attributed to biomass burn-ing. Though significant, this quantity of chlo-rine is much less than that from CFCs.

Finally, there is the claim that volcanoescontribute to atmospheric chlorine. In 1980, ascientific study estimated that the 1976 eruptionof Mount Augustine in Alaska released 159,000metric tons of hydrogen chloride (HCl) into thestratosphere. The study also discussed a volcaniceruption that occurred in California 700,000years ago in which about 262 million metric tonsof HCl were released into the stratosphere—significantly more than the Mount Augustineeruption. The ancient California eruption wouldhave released into the stratosphere the equiva-lent of about 570 times the amount of CFCs pro-duced in the world in 1975.

In the book Trashing the Planet, the authorconfused the two eruptions studied in 1980. Shestated that Mount Augustine released 262 mil-lion metric tons of HCl into the stratosphere in1976, which is causing the current ozone deple-tion. She mistakenly attributed the chlorineemission from the ancient California eruption tothe small eruption that occurred in 1976.

Maduro argues that Antarctica’s MountErebus, an active volcano that has been erupt-ing continually since 1973, is the cause of theozone hole over that continent. Maduro cites ascientific paper reporting that Mount Erebusemits more than 907 metric tons of chlorineeach day. He concludes that this continualcloud of volcanic chlorine is creating the ozonehole. However, what Maduro failed to report isthat Mount Erebus does not erupt explosively.Since an explosive eruption is necessary toshoot volcanic gas into the stratosphere,Maduro’s claim may be misleading. Most of theemissions from Mount Erebus rarely rise morethan one-half kilometer above the volcano’srim. Most gases and other volcanic materialsimply ooze over the side of the volcano, neverentering the stratosphere where they couldharm the ozone layer. After carefully reviewingthe latest scientific data, even Fred Singer con-cedes that volcanoes play a very minor role inreleasing chlorine into the stratosphere.

Scientists Respond to Criticisms

Atmospheric scientists admit that there aremany things they don’t know yet about ozonedestruction. For example, in 1992, researchersdetected large amounts of chlorine in thestratosphere over the Northern Hemisphere.This finding led them to predict significant lev-els of ozone loss over heavily populated areas.Fortunately, the prediction did not hold true.Critics quickly used this opportunity to chargethe scientists with furthering their own inter-ests—that is, seeking funding for research.

Scientists countered that they had notclaimed certainty in their prediction. Theyexplained that the Arctic region experienced anunexpected warming in January, and thestratosphere did not get cold enough for thepredicted ozone destruction to occur. Further,the scientists pointed out that those in themedia do not understand the uncertaintiesinvolved in making such predictions. Instead,the media gave the false impression that disas-ter was likely to happen.

Where Do We Go from Here?

Some scientists believe that a “middle-of-the-road” approach should be taken. That is,ozone destruction may not mean doom for theplanet—but neither should it be ignored and


assumed to be harmless. At least one industry is looking for alterna-

tives to CFCs. Soon after the Montreal Protocolwas ratified, DuPont, a major producer of CFCs,announced that it would willingly seek a safesubstitute for the ozone eater. DuPont acceptedthe scientific findings and treated them as alegitimate warning that demanded immediateaction. The company has begun producingHCFCs, an interim substitute for CFCs.Although HCFCs are an improvement overCFCs, they still cause some damage to the

ozone layer. DuPont and other chemical com-panies continue to search for ozone-friendlycoolants in response to data they find to be sci-entifically compelling. Unfortunately, the loserin this controversy is the public, which may notknow what to believe. Because the scientificevidence is so complex and still not completelyunderstood, the public is at the mercy ofexperts—and so-called experts—to interpret theevidence. The wisest course to take at this pointis to stay open minded and well informed onthe issue.

Review


1. What do scientists think is the cause for ozone depletion in the stratosphere?

2. How does the Montreal Protocol address the problem of ozone depletion?

3. What do critics of the ozone theory claim is the cause of ozone depletion?

4. What evidence have scientists put forward to counter the claims made by their critics?

5. Some critics think scientists are raising false alarms about ozone depletion. What reason dothey give for scientists making such dire predictions?

Decisions


1. Old car air conditioners, household air conditioners, and refrigerators may one day have tobe removed and replaced in order to safely destroy their CFCs. Should the cost of replacingthese products be the burden of individual consumers, or should the government help peopleto act environmentally responsible by subsidizing purchases of new, CFC-free appliances?Explain your answer.

2. How can you be sure that the scientific information you read is not biased, and that the datait cites are accurate? As someone concerned about the environment, what can you do tomake sure that you are receiving complete, unbiased information on an environmental prob-lem you read about or see on TV?

3. Imagine you are the editor of a magazine or newspaper that reports extensively on environ-mental issues. What guidelines would you implement to ensure that your writers andreporters correctly report scientific information surrounding environmental issues?


M any industries and utilities releasetoxic gases, such as nitrogen oxidesand sulfur dioxide. These gases pose

risks to human health and the environment.Acid rain and global warming, for example, arecaused by gaseous air pollutants.

The problem of reducing emissions of airpollutants is difficult to solve. Some industrieshave been unwilling to make investments intechnologies that reduce pollution because ofthe high cost. Companies making large invest-ments in antipollution technology might beforced to scale down their operations and evenlay off employees.

For many years, various laws have beenpassed to set limits on emissions and to forceindustries to use cleaner technologies. Theimpact of these laws has been limited, partlybecause of resistance by industries. This hasresulted in nonenforcement of the laws and indelays of improvement deadlines. In response,environmentalists have called for stricter laws,quicker enforcement, and stiffer penalties forviolators.

Recently, a new approach has beenproposed that appeals to many environmental-ists and many industrialists. The idea is toreward clean industry and penalize those thatcontinue to produce large-scale pollution. Thisconcept will be tested under the provisions ofthe Clean Air Act of 1990.

Encouraging EnvironmentalResponsibility

The Clean Air Act uses a new approachcalled “free-market” environmentalism. Insteadof simply placing limitations on emissions ofpollutants, the act establishes a “market” for pol-lution and clean air. Under the provisions of thelaw, which will go into effect in 1995, each util-ity company will be issued credit permits to emita certain quantity of sulfur dioxide. The amountof pollutant allowed per utility will depend uponhow much companies in the industry typicallyemitted in the past. Companies that have been

cleaner than the average will be granted permitsto release more pollution than companies withpoorer environmental records. The amountallowed per utility will then be decreased on ayearly basis. The goal is to cut emissions by 25percent by the end of 1995 and by more than 50percent by the year 2000.

To provide an incentive for reducing pollu-tion, the Clean Air Act will allow emissionspermits to be bought and sold. Any utility thatis cleaner than the level set by law will be ableto sell its extra credits to other utilities that arestill polluting above the allowed levels. This willgive the offending utilities more time to lowertheir own emissions levels—but at a price. Thehope is that the cost of exceeding pollutionlimits and the profit in falling below these limitswill encourage all the companies to becomemore environmentally conscious.

Companies that invest in cleaner technol-ogy would then be able to get back the moneyspent, in the form of the credit permits they sellto “dirtier” companies. This will encourage fur-ther investments that will modernize industry,improve air quality, and stimulate growth inother areas of the economy.

Environment for Sale?

There is another side to this issue. The newClean Air Act will allow clean air and the optionto pollute to be bought, sold, and traded on themarket. Critics claim that the atmosphere,which belongs to everyone, will now go to thehighest bidders. Profits could be made at theexpense of ordinary people and of the environ-ment itself. The enthusiasm with which somepolluters have greeted the act has heightenedthe concerns of some environmentalists.

According to these critics, it would becheaper for many industries to buy credits thanto make a real effort to improve the technolo-gies they use. These companies may still resistmaking environmentally desirable changes thatincrease short-term costs. Critics also claim thatover time, such a law could easily be weakened

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free-market environmentalism: is trading emissionspermits just selling the right to pollute?


to suit the interests of these industries so thatthey may never have to make the changesrequired.

According to critics of the Clean Air Act, citi-zens will have less control over the environmentthan they do now. They will have to breathe airpolluted by nearby utilities for the profit of moredistant ones that have sold their credits. With thegovernment regulating the process, control andenforcement may be difficult.

Some studies have suggested that one effectof the emissions permits may indeed be toimprove air quality—but only for some people.People who live in wealthier areas in which thereis little need for industry and the employment itcreates will benefit from cleaner air. Poorer areas,in which people are more likely to accept indus-trialization because of the employment it creates,may bear the brunt of increased pollution. Theonly alternative, according to critics, is for thegovernment to clamp down on polluters ratherthan creating a new market for pollution.

Internalizing Hidden Costs

The price of polluting the environment ishigh, in terms of health and the slow destructionof Earth itself. The pollution-credit idea mayallow a truer cost to be set for resources. If the

idea works well, the hidden costs of polluting willbe reflected in higher costs to polluters. Thesecosts would in part be passed on to consumers.

This reflecting of real costs is called “internal-izing externals.” In the case of emissions permitsmore of the cost of polluting would have to beabsorbed by those who pollute most extensively.This cost would have to be figured in, or inter-nalized, in projections as to expenses and profits.

The idea of internalizing externals can beapplied in a number of other ways in our soci-ety. For example, individuals who producelarger-than-average amounts of garbage couldbe required to pay more for garbage disposal. Incontrast, people who produce smaller-than-average amounts of garbage might be rewardedwith lower taxes and other incentives. The pro-gram would make everyone more aware of thehidden costs of polluting.

Environmental economists warn about“internalizing externals.” They fear that theindirect costs of environmental pollution thatcould show up abruptly in the price of goodsand services would have harmful effects on theeconomy. However, many of these expertsbelieve that gradually internalizing these hid-den costs will make for better decision-makingby society and a healthier and cleaner worldfor everyone.

Review


1. Why have industries resisted investing in technologies that would reduce the amount of pol-lutants produced?

2. Describe the approach to pollution control represented in the Clean Air Act of 1990. Includea description of the idea of emissions permits. State the arguments given in favor of the act.

3. Summarize the arguments against the trading of emissions permits.

4. Explain the concept of internalizing externals, and give an example.

Decisions


1. State your own opinion on the pros and cons of emissions-permit trading. Do you believethat the practice gives industries a right to pollute? Will resources belonging to everyonebecome the property of polluters? Explain your answer.

2. How would your opinion on emissions-permit trading be affected if you were the director ofa utility? If you lived near an industry that was buying credits to keep pollution levels high?If you lived close to an industry selling permits?


W hen you think of air pollution, youprobably picture industrial smoke-stacks or crowded highways. Indoor

pollutants, however, can be more dangerous tohealth than outdoor pollutants. People may beexposed to indoor toxics for longer periods oftime in closed, unventilated spaces. Also, circu-lation of air is generally slow indoors, especiallyif windows are kept closed. This allows pollu-tants to become concentrated in small areas.

Secondhand smoke is one of the mainsources of indoor air pollution. Sometimescalled mainstream smoke, the exhaledsubstances from smoking can contain harmfulsubstances. When inhaled, some of the toxicgases in secondhand smoke, such as carbonmonoxide, nitrogen dioxide, and hydrogensulfide, enter the bloodstream. The toxins canproduce symptoms of poisoning and long-termdamage to the circulatory system. Tars in thesmoke coat the lungs and can cause cancer.Nicotine constricts blood vessels and raisesblood pressure. Particles of partially burnedtobacco enter the lungs, resulting in emphy-sema, a serious breathing disorder.

The Danger to Others

Some of the dangerous pollutants ininhaled smoke are absorbed by the smoker, butthe exhaled smoke is still full of toxic materials.These materials may be breathed in by non-smoking people present. Nonsmokers alsobreathe in sidestream smoke, which is releaseddirectly into the air by the burning cigarette tip.Sidestream smoke contains even more toxinsthan mainstream smoke, including carbonmonoxide, tars, nicotine, and ammonia.

Nonsmokers who take in secondary smokefrom sidestream or exhaled smoke become“passive smokers.” The danger of toxins inhaledfrom passive smoking has become more obvi-ous in recent years, thanks to a number of stud-ies. These studies have shown elevated rates oflung cancer and higher death rates in non-

smokers who are married to smokers or whowork among smokers.

The effect of secondary smoke on infants andchildren is even more severe. Those whose par-ents smoke are much more likely than childrenof nonsmokers to develop bronchitis, pneumo-nia, and other respiratory infections. Pregnantwomen who smoke pass poisons through theirblood to their fetuses. Their babies are apt tohave lower birth weights than other babies aswell as higher infant mortality rates.

There is no “quick fix” to the problem ofpassive smoking. Air-cleaning devices or effortsto increase ventilation have been tried toreduce indoor secondary smoke. Studies haveshown that these measures are not very effec-tive. Efficient exchange of inside air with freshoutside air is more helpful, but installing andusing the proper equipment is costly. Separatingnonsmoking from smoking workers is not effec-tive as long as both are in the same room.

Limiting Smoking

Alarm over the dangers of smoking has ledsome nonsmokers to seek legal protectionagainst secondary smoke. Laws have beenpassed on state and local levels to limit smok-ing in offices and other public buildings. Non-smoking areas have been designated inrestaurants and office buildings; smoking hasbeen banned on airplane flights within theUnited States.

Some states, such as California, forbid smok-ing inside all state-owned buildings. Throughoutthe country, companies have gone even further.They have forbidden smoking not only insidethe workplace but on all company property,including outside grounds and parking lots.Some companies even refuse to hire smokers.Insurance companies often insist on higher pre-miums for companies that hire smokers.

The Issue of Individual Rights

The smoking habit is difficult to break.Many smokers enjoy their habit and do not

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are antismoking laws justified or too restrictive?


wish to quit. Some of them show little concernor are not convinced of the dangers to them-selves or to nonsmokers. However, some smok-ers have taken a responsible and reasonableposition. They accept limitations on smokingthat clearly protect nonsmokers, but they rejectlimitations in situations where others cannot beharmed.

For example, many smokers resent limita-tions placed on them when they smoke out-doors in the open air. They also resentdiscrimination in hiring. They believe theyshould be provided with smoking areas thathave been set aside for them. They resent whatthey feel is the extreme position of some anti-smoking activists who oppose smoking under

any circumstances, even when nonsmokersafety can be guaranteed.

Many people, including smokers and non-smokers, believe that adults should have theright to do as they please, as long as theiractions do not harm others. They feel that thisbasic freedom—the “right to smoke”—is beingtaken away from them.

The issues of health, individual freedom,and behavior control are all involved in thesmoking debate. In its decisions, society muststrike a delicate balance between the rights ofsmokers and nonsmokers. Reaching a workableagreement between these groups will requireincreased awareness and mutual respect andunderstanding.

Review


1. Describe the health problems associated with smoking.

2. What is the difference between mainstream smoke and sidestream smoke?

3. Why are both of these types of secondhand smoke dangerous to nonsmokers? What evidenceis there regarding these dangers?

4. What kinds of measures have been taken to limit smoking?

Decisions


1. What measures do you think should be taken to protect nonsmokers against secondarysmoke?

2. Explain how the issue of individual rights relates to the limitation of smoking.

3. Some nonsmokers believe all smoking should be banned. Explain your feelings on the issueof controlling the behavior of adults if that behavior is harmful only to them.

4. No serious attempt has been made to limit smoking within private homes. Do you think limi-tations should be placed on smoking in the home? Explain your answer.


H umans have colonized nearly everyecosystem on Earth. They havelearned to use the resources available

in each of the diverse environments theyinhabit, and, like other organisms, have alteredthe environment in which they live. For exam-ple, Native Americans of the Plains burned theprairie to enhance the growth of the grassesthat attract buffalo. Even the earliest agricul-tural societies diverted water to irrigate theirfields. In most cases, these changes did not dras-tically affect the natural balance of organismswithin local ecosystems.

Over the course of the industrial and post-industrial eras, the human population hasincreased exponentially. Growing populationsencroach on natural habitats in their search forplaces to live and sites for industries. This con-stant infringement has caused the destructionof the habitats of other organisms and has ledto the endangerment or extinction of manynative species.

In 1973, the United States governmentpassed the Endangered Species Act (ESA). Thepurpose of this law was to identify and thenrevive populations of endangered plants andanimals throughout the nation. The ESA isscheduled for reauthorization by Congress. Abattle over its goals and methods is alreadyraging. The combatants represent two differentpoints of view: those who think the act needsto be strengthened to effectively save endan-gered species and those who think it shouldgive priority to human rather than nonhumanneeds.

Human Needs

One of the most cherished American rightsis that of the individual to seek out opportuni-ties for success and work hard to achieve thatsuccess.The frontier ethic is an outgrowth of thebelief in individual freedom. It embodies theidea that the world and its resources are thereto be used, and that people have the right totransform natural resources into something that

is useful. Making profits from the exploitationof resources naturally stems from this right.

The frontier ethic is apparent in real-estatedevelopment. As the human populationincreases around metropolitan areas, buildingfor homes and businesses extends to openareas, away from the cities. These patches ofundeveloped land are often the last refuges ofendangered species—species whose populationshave declined drastically as their habitats weredestroyed by human activities. In some cases,enforcement of the ESA has prohibited buildingon these remnant habitats to protect endan-gered species living in them.

Property rights proponents argue that landdevelopment is right and natural becausehumans should be viewed as part of an ecosys-tem as much as any other organism. Therefore,people have as much right to use ecosystemsfor their needs as plants and animals do fortheirs. Critics argue that the human use of nat-ural resources in an ecosystem often destroysecosystems. Nonhuman organisms also exploitresources, but usually do so within the balanceof biotic and abiotic conditions that maintainthe ecosystem’s biological diversity and stability.By contrast, of the 990 species listed as endan-gered or threatened, many are endangered pre-cisely because human development of naturalareas has resulted in widespread destruction ofhabitats.

Some people deeply resent the limitationsthe ESA places on their right to develop land tomake money. Some landowners fear that if anendangered or threatened species is found tolive on their land, they will be prohibited fromdeveloping it. Because the land cannot bedeveloped, its property value might declinesharply. Many people who hold this view haveorganized groups such as the American LandRights Association and the Wise UseMovement. These organizations try to influenceCongress to rewrite the ESA so that it placesmore emphasis on the human right to own anddevelop property. The groups insist that theabsolute right of property owners and property

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should the endangered species act be strengthened?


developers to use their land as they wishshould, in all cases, take priority over the rightsof nonhuman species.

Revising the ESA

Congress defeated a compromise measureproposed by the property-rights proponents.This amendment to the ESA would haverequired property owners to be reimbursed bythe federal government for any loss of value ormoney they suffer if their land is prohibitedfrom development because of ESA provisions.

After carefully reviewing the proposal, mostenvironmental groups announced their opposi-tion. They contend that the amendment couldbe so costly to the government that it would bemore reluctant to list and protect endangeredorganisms. It would, in effect, weaken the pur-pose of the ESA.

Advocates of property rights are fightingaggressively for their cause because they fearthe ESA will be substantially reinforced. Theywant their concerns represented. Much of thescientific community, however, seeks changesin the ESA that will strengthen it. Scientistsbelieve that, as currently written, the processfor listing a species as endangered or threatenedtakes far too long. More than 80 species havebecome extinct while awaiting classification asan endangered species. The listing process mustbe streamlined if species are to be saved.

The ESA presently requires that recoveryplans for listed species “restore the listed speciesto a point where they are viable, self-sustainingcomponents of their ecosystems.” That meansincreasing the sizes of species populations to thelevel that is natural for their ecosystems. How-ever, studies have shown that recovery plansfor 28 percent of listed species set their popula-tion goals at or below the population sizes of thespecies at the time the plan was written, whenthe species were already endangered. In somecases, the population goals that were set werefutile because what little habitat was left couldno longer support a viable population of thespecies. Such species were seemingly dismissedby being classified as having “a remote chanceof recovery.”

A New Approach

Scientists have proposed a radically newapproach to saving species. First, they insist that

the ESA include guidelines for setting speciespopulation goals that are viable. Second, theESA should follow its current requirement thatspecies be preserved within their ecosystems. Todate, 70 percent of endangered species havebeen saved by being relocated to nonnativeecosystems; 64 percent have been saved solelythrough captive breeding programs. These fig-ures indicate that the species had been identi-fied as endangered far too late, when they werealready on the verge of extinction.

The best way to correct these problems,according to some scientists, is to save entireecosystems, before their populations are threat-ened. The ESA should identify remaining intactecosystems and set them aside for permanentpreservation. In this way, viable populations ofall native species will continue to exist in theirnatural state.

As a first step toward this goal, the U.S.Department of the Interior, which enforces theESA, was given $164 million to conduct anationwide National Biological Survey. Con-ducted by scientists and volunteers, the surveywould inventory plant and animal life in theUnited States. Without such a survey, it wouldbe impossible for the department to identifyhealthy ecosystems and to formulate effectiveplans to save them.

The Controversial Compromise

The Department of the Interior has begunexperimenting with new ways of saving endan-gered species by protecting entire ecosystems.Though in theory this new approach seemspromising, it has not proven flawless. Themethod’s first test-case is being carried out inCalifornia.

The California gnatcatcher is a tiny song-bird whose habitat, coastal sage scrub, hasdwindled to 121,000 hectares, only 10 percentof its original range. This chaparral-like habitatlies near the Pacific Ocean in a desirable areafor real estate. As 2500 pairs of the world’s lastCalifornia gnatcatchers struggle to survive intheir remnant habitat, developers are submit-ting plans for building in this area.

The Department of the Interior’s plan forsaving the gnatcatcher’s ecosystem represents acompromise. It allows developers to build in the

endangered ecosystem in return for a guaranteethat a specified number of hectares will remainuntouched. In theory, everybody wins. Thedevelopers can build in the endangered ecosys-tem without facing lawsuits, and some undevel-oped land is left to protect the gnatcatchers andother species.

Critics stress that this plan would workmost effectively when there is a more substan-tial amount of ecosystem to save. Thegnatcatcher has already lost 90 percent of itshabitat to development. Surely, they argue,allowing any further destruction of some of theremaining 10 percent would be devastating tothe survival of the gnatcatcher.

Landowners are also unhappy with theplan. They do not want surveyors trespassingon their property conducting species invento-ries. They insist that the National BiologicalSurvey is an intrusion on their privacy. They


Review


1. What was the purpose of the 1973 Endangered Species Act? What shortcomings in the lawprevented it from achieving its goals?

2. Why is the preservation of entire ecosystems considered more effective in saving species thandeveloping recovery plans for individual endangered species?

3. What is the National Biological Survey and how can it aid in species preservation?

4. Why do landowners and developers oppose the National Biological Survey and the preserva-tion of ecosystems?

5. How is the Department of the Interior’s plan for saving the California gnatcatchers ecosystema compromise between real-estate interests and environmentalists?

Decisions


1. Suppose the natural habitat of a rare species of bird is found in an area just outside your metro-politan area. Developers are interested in building homes and apartments in the habitat toaccommodate the increasing population. Environmentalists are opposed to the plan becausethey feel it will harm the already endangered species. What should be done?

2. Should the ESA be strengthened? Are there other compromises that can be made to protectplant and animal species and at the same time promote economic growth? Explain.

3. Suppose you invested your life savings in a piece of property on which you plan to build yourretirement dream house. Shortly after your purchase, a rare insect is found to live only onyour property, and environmentalists are trying to list it as endangered. If the insect dies outbefore it is listed, you will be free to build as planned. If not, the land will be protected andyour investment will be lost. how will you proceed?

also fear it may lead to their land being declaredbiologically valuable, preventing developmentand the possibility of business ventures. Theyfurther assert that the plan has no provisions bywhich they can challenge survey findings incourt. However, they admit that once compro-mises are reached and the preserves are decidedupon, they will not have the threat of ESA law-suits hanging over them.

The reauthorization of the ESA brings intoconflict two very different beliefs about the roleand rights of humans in the nature of theworld. On the one hand are those who believethat humans have every right to use the earth’sresources to benefit people, even at the risk ofendangering some other species. On the otherside are those people who believe thatuntouched ecosystems have a worth all theirown and that humans are responsible for pro-tecting those ecosystems and the species thatinhabit them.


T he United States faces a solid-waste dis-posal crisis. It is projected that half of thenation’s landfills now in use will close

within five years. Tipping fees paid by trashhaulers to dispose of garbage at landfills havedoubled in the last decade. Many states areexperiencing a shortage of potential landfillsites. Some smaller states in the Northeast payhigh tipping fees to out-of-state landfills toaccept their trash. The cost of building newfacilities to accept garbage is a primary concern;strict environmental regulations increase thecost of building and maintaining landfills.Where to locate new landfills is also a problem.Although everyone understands the need forwaste disposal, no one wants an unsightly,odorous mound in their neighborhood—the“not in my backyard,” or “NIMBY” syndrome.

In August 1990, the city council of Austin,Texas, adopted a five-year plan to expand recy-cling efforts and reduce the amount of wastegenerated. A “pay-as-you-throw” programwith variable-rate fees was tested. Customerswere charged according to the amount of trashthey generated each week: $6 for a 30-galloncan, $9 for a 60-gallon can, and $12 for a 90-gallon can. Stickers, costing $10 for a set of five, could be placed on any excess bags. Recyclable materials were collected along withgarbage.

Waste Reduction

Over the first six months of the pilot study,participation in the city’s curbside recyclingprogram increased from about 50 percent tomore than 80 percent. There was an increase inthe recyclable materials collected. As a result,34 percent of total waste was diverted from thelandfill. Eighteen percent of separately collectedyard wastes was diverted from the landfill. Theleaves and grass clippings were mixed withsewage and composted, producing Dillo Dirt, anatural fertilizer. The resulting reduction inwaste generation was 23 percent comparedwith that of similar neighborhoods not partici-pating in the pilot project.

Many communities around the UnitedStates have started variable-fee waste manage-ment programs. Some charge by the bag, sellingeither stickers or special bags, and some by vol-ume. Still others charge by the weight of thegarbage.

One of the oldest and best documentedvariable-fee programs is Seattle’s per-containerbilling system, begun in 1981. Similar toAustin’s program, the Seattle program chargesresidents a monthly fee for collection of trash,depending on the sizes of the cans they fill. Theprogram has increased the proportion of wastethat is recycled from 5 percent to 42 percent,and has decreased the amount of garbage destined for a landfill.

Conserving Resources

Many customers like the variable rate; theydo not pay for excess trash their neighbor maygenerate, and are rewarded for recycling andgenerating less garbage.

Participants of pay-as-you-throw programslike the variable-fee system for other reasons.The distributed recycling containers are uni-form in appearance, making the streets look alittle better on trash collection days. Residentshave become more aware of the environmentalhazards of waste disposal; they enjoy the feelingthat they are making a significant contributionto the environment.

The increase in the amount of materialsthat are recycled aids resource and energy con-servation. The production of a 100 percentrecycled aluminum beverage can saves 90 to 95percent of the energy needed to make the canfrom raw materials. Recycling paper not onlysaves energy, but for each metric ton of recycledpaper produced, 66 percent of the water used inpaper production and 19 trees are saved.

Not a Perfect Solution

A pay-as-you-throw program, such as theone in Austin, requires extensive research andforesight. Recycled goods must have a market,

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do “pay-as-you-throw” programs pay off?

or they will eventually end up in a landfill.Most communities do not include multifamilydwellings in their programs, mainly because ofthe difficulties in assessing waste generation inapartment or condominium complexes. To beeffective, a community must set up programs todeal with organic matter such as leaves andgrass clippings; community-wide composting,however, is difficult to carry out.

In addition to being difficult to organize,pay-as-you-throw programs are expensive. The distribution of cans and recycling bins iscostly. Designing the program and setting upnew computer billing systems require adminis-trative and technical expenses. The necessarycommunity education is also costly. The city ofAustin spent approximately $7 per householdon educational materials, including a monthlynewsletter, for the first six months.

Billing procedures pose a problem for somecommunities. Since many current computerizedbilling systems cannot handle a variable rate,new systems must be devised. Instead of includ-ing the garbage collection fee with other cityutilities on a single bill, separate billings may berequired, causing customer inconvenience.

Other objections have been raised. Infre-quent collection, such as the once-a-week col-lection in Austin, generates complaints aboutinsects and odor problems. Some opponents ofthis plan suggest that it encourages illegaldumping and backyard burning of garbage. Pro-grams that use stickers to charge per bag havereported stickers being blown off or stolen.

Alternatives

Critics of pay-as-you-throw programs thinkthat communities must also explore other waysof minimizing landfill trash. The incineration ofsolid wastes is an option. Other industrial coun-tries routinely incinerate a significant percentageof their wastes. For example, Japan incinerates50 percent of its nonrecyclable wastes. Com-posting, which could produce fertilizer in addi-tion to reducing trash volume, is anotheroption. It may be idealistic to expect all Ameri-cans to voluntarily reduce waste generation,participate in recycling, and buy products madewith recycled materials. Therefore the searchfor new waste disposal solutions continues.


Review


1. What was the purpose of the “pay-as-you-throw” program in Austin, Texas?

2. What is variable-fee pricing for waste management?

3. Do the results of the pilot study of Austin’s new plan look promising? Explain.

4. How does recycling affect energy conservation?

5. What are some objections to “pay-as-you-throw” programs?

Decisions


1. Should the federal government be involved in recycling efforts or other programs to reducegarbage? Explain your answer.

2. Do you think recycling programs should be voluntary or mandatory? That is, should con-sumers be charged for the amount of trash that they throw away or be fined for mixing recy-clable materials with other wastes?

3. Some communities have commingling programs, in which city workers separate recyclablewastes from collected trash. How does this method affect the cost and effectiveness of therecycling and waste reduction effort? Does commingling give consumers incentive to reducewaste generation? If you were the mayor of a city, would you support such a program?


F or every political issue, from gun controlto health care to international policies,there are many different corporations,

associations, and special interest groups thatinfluence members of Congress. These groupssend lobbyists as representatives to Washington,D.C., to persuade individuals in Congress tosupport government policies that favor thegroups’ interests.

Lobbyists represent special interest groupssuch as the auto industry, small businesses,religious groups, tobacco farmers, and environ-mentalists concerned about endangered species.Often one group will join together with othergroups that hold the same views about an issueto form a coalition. These same groups maydisagree on other issues.

Lobbyist groups often support candidatesfor a political office by contributing money totheir campaigns. These groups, called politicalaction committees (PACs), control funds setaside specifically for campaign contributions forvarious political candidates. Usually the PACsare associated with large corporations or laborunions. Sometimes they are affiliated with aparticular cause. A campaign contribution froma PAC serves two purposes: it can convince acandidate to back the group’s interests, or if thecandidate is already sympathetic to the group’sconcerns, the contributions can help elect thatperson to a political office where he or she willhave the power to influence the passage (orblockage) of laws.

Lobbying is protected under the First Amend-ment to the Constitution of the United States.This amendment guarantees freedom of speech,freedom of the press, and the right to “petitionthe Government for redress of grievances.” Lobbying is a way of petitioning, or askingmembers of Congress to represent the group’sinterests when considering certain laws. Thisguarantee makes it difficult to restrict lobbying.

Benefits and concerns of Lobbying

Lobbying is useful for several reasons. Lob-byists enable group concerns to be heard andgive Congress an idea of which issues areimportant to different groups. Because there areso many issues that Congress must consider,most politicians have limited knowledge aboutspecific issues and the short-term and long-termeffects of the passage of certain laws. Specialinterest groups may bring important new infor-mation to the attention of members of Congressabout the issues. Lobbyists also speak for thosepeople or things that do not have much influ-ence in Congress, such as children, the poor,the environment, and endangered animals.

Many people fear that lobbying in somecases is a form of bribery—that PACs can buy apolitician’s vote. There have been instanceswhen politicians voted in favor of groups thatdonated very large sums of money, even whentheir views did not represent the opinions ofthe general public. The largest coalitions withthe most money can launch the most influen-tial campaigns for their causes. Sometimes billsare defeated not because the public objects tothem, but because lobbyists of powerful groupshad enough influence to block their passage.Some people question if this impedes the demo-cratic process.

Acid Rain

An example of how lobbying can affect lawscan be seen in one effort to reduce acid rain.When fossil fuels are burned, sulfur dioxide andnitrogen oxides are released into the atmos-phere, making precipitation, whether rain,sleet, snow, more acidic. Known as acid rain,this precipitation falls into lakes and streamsand seeps into the soil. Over time, this alters theenvironment enough that many species ofplants and animals die, affecting the balance ofthe entire ecosystem.

In 1993, a bipartisan bill was passed in aHouse of Representatives committee that tried

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should lobbying be restricted?

to limit the amount of sulfur dioxide and nitro-gen oxides released into the atmosphere. Beforethe bill could be presented to Congress, a lobbygroup named Sensible Control of Acid Raingenerated more than half a million computerletters to key members of Congress and theirconstituents. The letters indicated that the costfor implementing the restrictions in this billwould be greater than $100 billion and thatutility rates would increase more than 30 per-cent. In contrast, Congress had estimated a costof between $26 billion and $50 billion and a 2percent increase in utility rates. The campaigncontributed to the defeat of the acid rain bill.

The lobbying organization was the creationof a Washington, D.C., public relations consult-ing firm. Interestingly, the funding for this effort(over $2 million) was provided by severalpower companies that were all major producersof sulfur dioxide pollution.

Greenhouse Gases

Vehicles that are powered by the burning offossil fuels consume more than a third of theenergy used in the United States and produceabout a third of all carbon dioxide (CO2) emis-

sions. Carbon dioxide is considered a “green-house gas,” and is suspected to cause globalwarming. In October of 1993, the Clintonadministration proposed the Climate ChangeAction Plan, which included 50 initiatives forreducing the buildup of carbon dioxide in theatmosphere. These measures included incen-tives to the use of public transportation, newenergy-efficiency standards for householdappliances, initiatives to encourage the use ofmore efficient lighting systems, and tighter reg-ulation of the release of methane from landfills.Lobbyists for environmental groups, such as theSierra Club, opposed the plan because the mea-sures proposed were offered merely as guide-lines that groups were supposed to adoptvoluntarily. The plan also failed to includeenergy-tax increases to promote conservationof natural resources and to raise the standardsof fuel efficiency for automobiles. The GlobalClimate Coalition, a group of trade associationsand private companies, were pleased that thePresident had faith in their willingness to com-ply with his recommendations. The auto indus-try and coal-burning power companies wereinfluential in keeping mandatory energy taxesand pollution fines out of the plan.


Review


1. What is a political action committee? How does its contributions influence the making oflaws?

2. Why is lobbying important?

3. What are some concerns about the power lobbyists?

4. How has lobbying affected the outcome of laws involving environmental issues?

Decisions


1. Should lobbyist groups be prevented from offering misleading information in their cam-paigns? Does this violate their First Amendment rights?

2. Suppose lobbying were prohibited by law. How would this affect the way members of Con-gress vote on specific issues, such as higher fuel-efficiency standards for automobiles? Wouldpoliticians and the public be as well informed? Would politicians be more likely to vote infavor of the majority of people they represent? Explain.


B efore a pesticide, a drug, or a new scien-tific technique can be used, the risks ofusing the method must be weighed

against the benefits. Some drugs that proveeffective against a particular microorganism orsymptom have harmful side effects. Some pesti-cides, for example, can increase food produc-tion, but may be harmful either to the farmworkers who apply the pesticide or to the con-sumers who eat the produce. A vaccine maycause a few people to become ill with the samedisease against which the vaccine is supposed toprotect. Radiation exposure usually producesharmful effects in humans, but the risk of someexposure may be small compared to the cost ofprotection.

Risk assessment is important because itallows government policies to be made in arelatively objective, scientific way. It provideslawmakers with information about possibleharmful effects on humans or other organismsor the environment as a whole. Lawmakers cancompare these risks to either the benefits ofusing the method or chemical in question or tothe cost of preventing potential side effects.Then they can make decisions regarding its use.

Ideally, risks are evaluated by scientific stud-ies. For example, to determine the risk of using acertain chemical pesticide, a variety of tests maybe conducted. Laboratory tests on nonhumanmammals might demonstrate how harmful thechemical is. Scientists often examine case studiesof patients suffering from ailments thought to becaused by the chemical. Also, studies can mea-sure the amount of pesticide still left on producethat has reached the market. Then scientists candetermine whether or not this amount of resid-ual pesticide is likely to harm people who eat theproduce. The risk is then compared to the bene-fits of using the pesticide, such as increased foodproduction, and the costs of limiting the risk ifthe pesticide is used, such as techniques toremove residues. After this analysis, if the chemi-cal is considered dangerous enough to eitherfarm laborers or consumers, it may be bannedfrom use as a pesticide.

There are, however, limitations on the relia-bility as well as the practicality of using riskassessment to make policy decisions. One prob-lem is that the risk itself is difficult to determineand may be debated by other scientists. Resultsfrom laboratory tests on nonhuman mammalsdo not necessarily apply to humans. Becauselaboratory animals are much smaller thanhumans and have different physiological char-acteristics, it is difficult to determine whatamount of exposure in humans is equal to ahazardous exposure in lab animals. Further-more, risk assessment is expensive because sci-entific experiments are time-consuming andcostly. Since there are so many possible healthhazards, it is impossible to individually test eachspecific situation.

Radon Risks in the Air

One can observe examples of both the ben-efits and the limitations of risk assessment bylooking at the debate over which laws shouldbe passed to protect the public from radon pollution. Radon is a colorless radioactive gasthat is formed by the radioactive decay ofradium in Earth’s crust. It occurs naturally invarying amounts in air and water. According tothe Environmental Protection Agency (EPA),anywhere from 7,000 to 30,000 people per yeardie of lung cancer as a result of their exposureto radon indoors. This estimate has been chal-lenged, however, since it was based on studiesof uranium miners exposed to high amounts ofradon and radon isotopes. Another governmentagency, the Department of Energy (DOE), isone of the EPA’s critics. The DOE claims that theeffects of low-level radiation some people areexposed to cannot be accurately determinedfrom studies of miners. A public-awarenesscampaign was initiated, however, to alert thepublic to the risks of radon. The warning wasintended to give the public the opportunity totest levels of radon in their homes and makedecisions regarding protection from exposure.

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risk assessment

Radon in Drinking Water

The EPA has been trying to decide whataction, if any, needs to be taken to protect thepublic from possible harmful effects of radon indrinking water. In 1986 Congress reauthorizedthe Safe Drinking Water Act, giving the EPA the responsibility of proposing limits for 83 contaminants, including radon, in drinkingwater. The EPA’s report estimates that each year192 cancer deaths can be connected to radon indrinking water. The report proposes keeping thesame strict limits the agency recommended inJuly 1991. The EPA projects that this limitwould reduce the number of cancer deaths to107 per year.

Critics of the EPA’s report say that the esti-mates may not be accurate, since they werebased on studies of xenon, a gas similar toradon. Some critics also argue that tests need tobe done on nonsmoking households to isolate

radon as a possible cause of cancer. These stud-ies are expensive, however.

The cost of reducing radon in drinkingwater to acceptable levels is also an issue. TheEPA estimates that the reduction will cost tax-payers $272 million per year. Since 85 lungcancer deaths will be avoided annually fromthis action, each life saved will cost $3.2 mil-lion. The decision then comes down to whetheror not reducing radon in drinking water isworth the price.

Finally, opponents of strict regulation ofradon claim that there are more pressing healthissues that need the EPA’s attention and govern-ment funds. Other hazards that pose more obvi-ous risks to human health should be givenpriority over radon. They claim these hazardsdeserve more research, more funding, andmore immediate action than risks, like radonexposure, that affect fewer people.


Review


1. Why is risk assessment important?

2. How are risks estimated?

3. What are the drawbacks of risk assessment?

4. Which risk assessment approach do you think the EPA studies on radon in drinking waterused? Explain your answer.

5. What effect will reducing the maximum contaminant level of radon in drinking water haveon public health? What are the costs of implementing these limits?

Decisions


1. As a member of Congress, what action would you take regarding the EPA’s recommendationsto reduce the maximum amount of radon in drinking water? Defend your position.

2. Considering the costs of experimentation, should scientists conduct more tests to determinespecific health risks, or should they use studies from similar situations? Explain your answer.

3. Propose a plan that would help scientists better communicate their results. Could this lead tomore accurate risk assessment? Explain your answer.


Answer Key

Issues and Decisions 1

Review

1. The pressure in the volcano drops, magma rises, gases escape from the volcano, and the gravita-tional field changes.

2. Nothing can be done to prevent an eruption.

3. The risks can be reduced by organizing evacuation strategies, accurately predicting volcanic activ-ity, and predicting and physically diverting the paths of lava flow.

4. Predictions are not always accurate and may lead to unnecessary evacuation. Taking measure-ments near a volcano is dangerous. Monitoring and planning strategies are expensive.

Decisions

1. Responses will vary. Students might suggest that international agencies, such as the UnitedNations, should be responsible for raising funds. Most students will probably say that developingcountries should be given financial aid for monitoring and evacuation programs.

2. Accept all logical responses. Some students might favor such laws because they would protectlives and property. Others might point out that such laws could hurt regional economies, andthat volcano prediction and evacuation programs could be used to minimize the risks to peoplewho purchase property near volcanoes.

3. Responses will vary depending on the relative importance students place on each option. Stu-dents’ choices should be supported with logical explanations.

issues and decisions 2

Review

1. Echolocation is the method by which aquatic animals use sound to locate other underwaterobjects. Human-generated undersea noise interferes with the sounds produced by the animals,impairing their ability to locate underwater objects.

2. Oil drilling, undersea explosions, ship engines, and scientific research are some sources of oceanicnoise pollution.

3. A 120-decibel level will prohibit some types of marine research that require producing underwa-ter sounds that exceed 120 decibels, including some studies of global warming.

4. The moving lights might be annoying and disorienting to people, similar to the way underseanoises affect marine mammals.

Decisions

1. Accept all logical responses. Students may believe that underwater noise could be justified if itpromoted a better understanding of oceans or marine life or if it were used to obtain essentialresources, such as oil.

2. Students’ responses should show an understanding that the 195-decibel policy represents a com-promise that will allow certain human activities in the oceans while attempting to minimizeharmful effects on marine animals.

3. Responses will vary depending on how students feel about the issue of oceanic noise pollution.Accept responses that include logical explanations for the recommendations made.


Review

1. Global warming may change weather patterns and ocean currents, increase sea levels, causechanges in ecosystems, and lead to the extinction of species.

2. Climatic systems are very complex. Also, the many interactions that relate to ecosystems make itvery difficult to predict the effects of global warming on climate.

3. Such standards would slow down the development of industries that are important to theeconomies of the developing countries.

Decisions

1. Accept all logical responses. Students who support such a policy might explain that because masstransit contributes less to air pollution per person than cars do, it should be subsidized in thisway. Students who object to the policy might argue that revenues obtained from privatemotorists should be spent on highway improvements and other automobile-related expenses.

2. Responses will vary, depending on how serious students think the problem of global warmingreally is. Those who do not think global warming is an urgent problem may be unwilling to makedrastic changes in their lifestyles and to see the jobs of millions of people put in jeopardy. Stu-dents who think that global warming is a serious threat may be willing to support such a policy.


Review

1. The produce is being monitored for the presence of Medflies, which is an introduced species thatdestroys fruit and vegetable crops.

2. The ballasts are filled with water that carry organisms native to the areas from which the shipsdeparted. The water is released from the ballasts into the harbor, thereby introducing alienspecies to the harbor ecosystem.

3. Honey production in Brazil increased sixfold after the African bee was introduced. The escape ofAfrican bees has increased their range over areas where they outcompete honeybees for resources.

4. The game fish are stocked to promote sports fishing. The introduced fish species may lead to theendangerment or extinction of native fish species.

Decisions

1. Responses will vary but should show an understanding of the arguments for and against thestocking of game-fish species.

2. Responses will vary. Students might suggest growing kudzu plants in confined areas, such asgreenhouses, so they can be grown without harming ecosystems.


Review

1. Both exist in warm, tropical environments; both are home to diverse species of organisms; bothhave potentially beneficial species that have not yet been identified; both are vital to the environ-mental health of the planet.

2. Coral is made up of colonies of polyps, animals that shelter zooxanthellae and supply them withcarbon dioxide; the algae, in return, supply the polyps with food and oxygen.

3. Scientists are unsure; it may be due to global warming caused by an increase in carbon dioxideand other gases in the atmosphere, or simply due to natural fluctuations in global temperature.


4. Coral reefs are damaged by boat and ship groundings, dropped anchors, irresponsible tourism,and dredging of the ocean for sand.

5. They serve as natural barriers to prevent storm damage, they supply food, and they attracttourism. Some coral-reef organisms produce chemicals used to make medicines.

6. The uncertainty of the true cause of bleaching, the cost of research, and the economic depen-dence of some countries on the reefs must be addressed.

Decisions

1. Responses will vary. Rather than prohibiting all fishing near coral reefs, students might suggestregulating how many fish are caught, where they are caught, and/or when they are caught.

2. Students may say that they are unsightly, may leak chemicals and pollute the water, and mayresult in oceans becoming dumping grounds for trash. Some students may favor artificial reefs, inspite of their drawbacks, because they can help establish marine ecosystems similar to thosefound near natural reefs. Other students may be opposed to artificial reefs because they believetheir drawbacks outweigh their benefits.

3. Responses will vary. Students might say that uniform international regulations are necessary toensure the health of the oceans. The activities of individual countries that benefit from theexploitation of ocean resources could be monitored. Difficulties in establishing international reg-ulations include establishing consensus among countries with varying interests, deciding howregulations will be enforced, and determining penalties for violations that are fair and impartialfor developed and developing countries.


review

1. Hydrocarbon fingerprinting is a process in which the molecules in crude oil are analyzed in orderto match the oil to its place of origin.

2. The two main opposing views are that the Sound is recovering very well, according to Exxonresearchers, and that the Sound is severely damaged and will need many years to recover,according to government and independent researchers.

3. The presence of deepwater oil seeps combined with diesel oil provides a fingerprint similar toValdez crude oil.

4. Many scientists feel that an organism metabolizes hydrocarbons into molecules that bear noresemblance to the original molecules in the oil.

5. This article touches upon the issue of slanted, or biased, research. Slanted research may be con-ducted in order to gain results that support one’s views or interests.

Decisions

1. Many view the Exxon research with suspicion because the Valdez oil spill was of such great mag-nitude that it is difficult to believe that the Sound is recovering as well as Exxon says it is. Also,because Exxon is the firm responsible for the spill and a great deal of money is involved, it seemsunlikely that they, or any firm in their position, would be able to conduct damage studies objec-tively. Answers will vary according to the student’s familiarity with the Valdez oil spill.

2. As an impartial judge, you might request that both Exxon and the NOAA provide more detailconcerning what happens to hydrocarbons after they have been metabolized by organisms. Youmight want Exxon to provide examples of instances in which it was possible to clearly identifyhydrocarbons after metabolic activity.

3. Students are likely to state that many angry citizens would object and seek a new trial for thecase. The original 40,000 citizens who brought the class-action suit to court are bound by the


outcome of the trial. However, there may be boycotts of Exxon products. Public officials who citi-zens feel may not have done a good job may not be reelected. As governor, you may be con-cerned about your reelectability, and you may wish to pursue the possibility of a new legalapproach against Exxon. You may also wish to impose strict regulations on single-hulled tankers.


Review

1. Levees are walls built along stream channels to hold back floodwaters.

2. If levees are built upstream, the water that would have spilled over the banks there remains con-tained, increasing the energy of the stream as it travels downriver. This increases the risk offlooding downstream.

3. Levees prevent the natural flood cycle from occurring. Wetlands along the floodplain are notreplenished with water and nutrient-rich sediments.

Decisions

1. Rivers provide people with transportation and a ready water source.

2. Levees and dikes would have to be removed, businesses along the river would either have tomove or risk frequent flooding, and transportation of goods along the river would be more diffi-cult. Residential and commercial property owners would object strongly, fearing floods and prop-erty damage and devaluation.

3. Answers should reflect an understanding that, without periodic flooding, farmlands would losetheir source of nutrients.


Review

1. Irradiation breaks chemical bonds in the organisms, thereby destroying their genetic material. Asa result, the organisms die or cannot reproduce.

2. The loss of nutrients in irradiated food may lead to problems, such as weight loss and miscar-riages, in organisms that eat the food. The long-term accumulation of RPs in the human bodymay be detrimental because some RPs are known carcinogens and mutagens.

3. Food irradiation may reduce the incidence of food poisoning by killing harmful organisms on andin harvested food. It may also reduce the need to apply toxic pesticides and preservatives to food,thereby exposing consumers to fewer harmful chemicals and reducing environmental pollution.

Decisions

1. Students’ responses will depend on their feelings about the safety of food irradiation and theimportance of consumer awareness.

2. Responses should show an understanding of the advantages and disadvantages of irradiated food.


Review

1. A large surplus of fish resources one year may encourage fisheries to invest more money inexploiting the supply, resulting in a serious depletion of fish resources shortly thereafter.

2. Established catch limits and fishing seasons give the suffering fish populations time to replenish.


3. The new law gives the federal government more power over the fishing in shallow waters, for-merly regulated by the individual states. If the states do not agree on catch limits and fishing sea-sons, the federal government can declare a moratorium for affected species.

4. Many workers lose their jobs; very short seasons can influence the health and safety of the workers.

5. Overfishing, dam building, pollution, and habitat loss contribute to declining fish populations.

Decisions

1. Responses will vary, but students should recognize that the economic health of the communitydepends, in the long term, on not depleting nearby stocks of fish by overfishing them.

2. Accept all logical responses. Most students will answer that the removal of all legislation regulat-ing fishing will have an adverse effect on marine ecosystems.


Review

1. Fish is high in protein and low in cholesterol. Many species contain large amounts of omega-3fatty acids, thought to help prevent heart disease.

2. Fish, shellfish, mollusks, and seaweed can be produced.

3. The raising of fish and other seafood is less harmful to the environment than raising cattle forbeef. It can also be used to restock depleted supplies of fish and protect endangered species.

4. The raising of fish in closed areas and the wastes they produce can alter the surrounding environ-ment, endangering nearby populations of fish and other organisms.

5. Consumers may object to the taste of seaweed or the taste and texture of farm-raised fish. Theymay also object to the antibiotics and hormones sometimes used in aquaculture.

Decisions

1. Establishing an underwater farm is initially costly. There may be opposition from animal rightsand environmental groups, and lack of public interest in buying aquaculture products. A federalaquaculture program might designate areas for the development of aquaculture, provide taxincentives for investors, run an advertising campaign to increase the public’s knowledge of aqua-culture, etc.

2. Opinions will vary but should show an understanding of the advantages and disadvantages ofaquaculture that would affect its profitability.

3. Students might say that laws should regulate the locations of underwater farms, how the farmsmust be maintained, and the kinds of chemicals used to treat fish and farm-raised organisms.


Review

1. Overexposure to pesticides can result in cancers, birth defects, reproductive problems, nausea,convulsions, even respiratory paralysis in extreme cases.

2. Many pesticides were created during wartime, either to protect soldiers from disease, to kill theenemy’s crops, or to thin jungle foliage.

3. The employer must supply safety equipment and training, a place to wash, access to emergencymedical care, and notices of quarantine of recently sprayed areas.

4. Alternatives include predators, parasites, and pathogens; traps, screens, “bug zappers,” and hor-mones; and the planting of other species to repel insects.


Decisions

1. Some students may argue that it is worth the possible health risks to prevent starvation; othersmay argue that a global ban is needed to protect ecosystems that may be affected by its use.

2. Responses will vary.

3. Responses will vary. Students may think local government has the right to regulate because of localenvironmental situations, or they may think additional restrictions are unfair to local industries.


Review

1. Green technology would decrease pollution, decrease the demand on nonrenewable resources,and increase profits for the automobile industry.

2. City planners would have to concentrate on the broader aspects of transportation; focus on theorganization of new systems around industrial centers; and redistribute suburban transit systemsto allow more commuters to use mass transit.

3. Green technology would be most beneficial for sparsely populated, rural, or outlying areas,because these areas would need the most individualized transportation considerations. Privategreen-vehicle ownership would work best under these circumstances.

4. Mass transit would be most beneficial in densely populated industrial centers and suburbs,because these areas generally contain the most people traveling to the same destinations at regu-lar intervals.

5. Drawbacks of developing green cars are that the development is very expensive and time-consuming; sponsors and the automobile industry might not be willing to make changes; peoplemight not want to spend money on the new vehicles.

6. Expanding mass transit systems would entail, in some cases, complete restructuring of cities andcommunities. Entire routes and schedules would be altered, and a period of transition would beneeded, making the task large and potentially confusing.

Decisions

1. Some materials from the outdated cars could be recycled and used again. Insurance for the newcars would have to be transferred from the old ones.

2. Give financial incentives to businesses that provide car-pooling services or are located near majormass transit routes.

3. Students might suggest that they would increase mass transit in outlying areas; sponsor adver-tisements encouraging the use of mass transit and car-pooling; or create a special lane on high-ways and major routes specifically for car-pool vehicles.

4. Answers should demonstrate an understanding of the limitations and benefits of mass transit use.


Review

1. Nuclear waste is very toxic, highly corrosive, and its radioactivity is very long-lived.

2. Seawater is corrosive and would spread released waste quickly.

3. Yucca Mountain is isolated, geologically stable, and far above groundwater.

4. Yucca Mountain could experience a large volcano or earthquake. It may also be vulnerable tointrusion by groundwater.


5. WIPP is a planned underground repository for radioactive waste in New Mexico. It consists ofcaverns cut out of a deep salt deposit. The plan had been to store many drums of high-levelradioactive waste at the site and test the surrounding area for contamination. Opposition fromthe state caused the DOE to abandon plans to test waste storage at the site.

Decisions

1. Answers will vary.

2. Concern will probably be greater if the site is nearby. There should be concern in any casebecause a serious accident or leakage can affect areas even at great distances from the site.

3. Answers will vary, but should be supported with facts from the essay.


Review

1. Erosion removes topsoil that is essential in supporting all plant life, including agricultural crops.Eroding soil also washes chemical pollutants into natural waterways.

2. The movement of water through the furrows causes rapid soil erosion. Clay particles clog soil andprevent plants from taking up water.

3. PAMs are polyacrylamides, large molecules that can develop a negative charge and attach to posi-tively charged clay particles, causing soil to hold together and resist erosion by moving water.

4. Short-term advantages include the near elimination of irrigation-related soil erosion and cloggingof soil pores. The long-term advantage is that the eventual loss of valuable farmland and otherserious effects of large-scale erosion are greatly reduced.

5. Short-term disadvantages include expense, time, and care associated with treatment. Currently,there are no long-term disadvantages known.

Decisions

1. Responses will vary. Students should consider the possible effects of erosion on future crop yieldsand the more far-reaching effects of irrigation-related erosion. A major farming decision involvesweighing the expense of using sounder methods of farming and irrigation to minimize erosionagainst the desire to farm more intensively and cheaply, maximizing profits at the expense of soilquality. Most students will probably express a desire to use sounder methods, but will recognizetheir options are limited, given their low financial resources.

2. Responses may include erosion-preventing legislation that would serve the general good. Studentsmight include a provision for a transition period and for financial assistance to eligible farmers.

3. Accept all logical responses. Students should address the causes of erosion, including nonrotationof crops to increase yields, cutting trees for fuel or profit, etc. Some students may suggest com-bined international efforts to limit these practices and to provide education, materials, equip-ment, and other assistance.


Review

1. Dangers include many health problems, including increased poisoning and cancer cases, frompossible environmental contamination.

2. Students may say that jobs will be created and economic influence of minorities may beincreased.

3. Possible arguments include: there are various health and safety risks, people are being takenadvantage of, and racial prejudice affects decision making.


4. Sites are selected in areas predominantly populated by racial minorities, relying on the belief thatthese people are usually less affluent and more desperate for new employment opportunities.They may therefore be less likely to oppose construction of dangerous facilities.

Decisions

1. Probable degree of risk (long-term and short-term), economic advantages for self and the com-munity at large, and the possible exploitative motivations of proponents are among the factorsthat might be considered. Students’ opinions of the desirability of the plan will vary, but somemay argue that the long-term risks outweigh the possibility of short-term economic gain.

2. Responses will vary. Some students will feel it is simply logical and realistic to factor in demo-graphic information. Others are apt to feel that unacceptable racism is involved in any such fac-toring, however well-meaning.

3. Some students will argue that the economic advantages are apt to be greater than the risks andthat lower income people should be allowed to take those risks if they wish. Other students willargue that the lack of economic options for these people does not justify their exploitation.


Review

1. In one method, drums containing sludge would be attached to a heavy nose cone and sunk. Inanother, sludge would be sent through a long hose to the sea floor. In a third, an elevator wouldlower sludge from two ships to the sea floor.

2. More area is available on the sea floor than on land, so space and land-pollution considerationswould no longer be an issue.

3. Material would not be carried upward or drift significantly, so effects would be confined to thesea floor. Relatively few organisms live on the sea bottom, so the effect on ocean life would beminimal. Sludge might even enrich the sea floor with nutrients that organisms can use.

4. Damage to any ocean organisms is unacceptable, even those living on the sea floor. Damage todeep-sea organisms could affect other organisms, given the complexity of interactions amongorganisms. The effects of using the ocean as a dumping ground cannot be predicted easily andcould prove highly damaging over the long term.

Decisions

1. Responses will vary. Students should recognize the difficulty of obtaining conclusive data aftersuch a short period of time, given the complexity of the systems involved and the possible longlag period before effects can be observed. They should also be aware of the advantages and possi-ble dangers inherent in such a program.

2. Student opinions will vary but should be justified by reasonable assessment of the pros and cons.

3. Students may say that such a situation could sway them to support deep-sea dumping, but theyshould not become insensitive to the larger environmental issues involved.

4. Students should be aware of the dangers involved in repealing protective legislation.

5. Suggestions will vary. Each should be workable to some degree and should offer at least oneadvantage over proposals already made.


Review

1. High dams can be used to divert fresh water for industries, irrigation, and personal use and toproduce electricity for personal and industrial use without polluting the environment.


2. A high dam creates an enormous lake that floods the surrounding land, thus necessitating therelocation of people living in the area.

3. When irrigation water evaporates from the soil, it leaves a residue of salt that is harmful to plantgrowth.

4. The construction of high dams is expensive, harmful to the environment, and can lead to morehuman diseases in the area.

Decisions

1. Responses will vary depending on the relative importance students place on human needs andenvironmental concerns. As a compromise between the two interest groups, students might sug-gest establishing energy-conservation measures in the cities to reduce the demand for electricity,and releasing less water through the dam, for shorter periods of time.

2. Responses will vary depending on how students feel about the rights of governments. Studentsshould recognize that if nations did not have the right of eminent domain, they might not be ableto establish certain programs beneficial to the common good.

3. Accept all logical responses. Students might suggest that international agencies, such as the United Nations, be responsible for informing developing countries about the negative aspects oflarge-scale water projects. Alternatives should be encouraged, such as the construction of small,local dams and the establishment of less damaging irrigation systems. Foreign aid might be allo-cated specifically for these purposes.


Review

1. Burning spilled oil is inexpensive, removes oil faster than mechanical methods, does not producehigh concentrations of pollutants, and may remove up to 99 percent of spilled oil.

2. Burning of oil poses a danger to humans and wildlife in coastal areas, produces toxic air pollu-tants that are dispersed in all directions, and does not completely dissipate surface oil or oil that isheavily mixed with water.

3. Bacteria and algae that eat oil are applied to oil spills. Fertilizers are also added to speed up thedegradation of oil by microbes.

Decisions

1. Answers will vary depending on students’ opinions of the safety and efficacy of burning oil spills.

2. Some students may believe that the potential benefits of burning oil spills outweigh the risks oftest spills in the ocean, particularly if steps are taken to choose appropriate sites and to containthe spilled oil during the testing. Others may believe that the potential risks posed by test spillsare too great to justify. Students’ agreement or disagreement with the EPA will depend on theirfeelings about test spills in general.

3. Accept all logical responses. However, most students will probably say that bioremediation is theleast environmentally damaging as long as genetically altered microbes are not used.


Review

1. Scientists think ozone depletion is caused by the release of human-made CFCs into the atmosphere.

2. The Montreal Protocol calls for a 35 percent reduction in CFC production by the year 2000 and acomplete ban of CFC production after the year 2000.


3. Critics think ozone depletion results from natural sources of chlorine, including the oceans,marine organisms, volcanoes, and the burning of biomass.

4. Scientists point out that because natural sources of chlorine are soluble in water, they would bewashed away by rain before reaching the stratosphere. CFCs are insoluble in water and wouldtherefore reach the stratosphere after being released.

5. They think that by raising such concerns scientists hope to get more funding for their research.

Decisions

1. Responses will vary depending on how students feel about the role of government in the privatelives of individuals.

2. Students should recognize that getting information from various sources, both for and against aparticular issue, will help them form a more unbiased view on an environmental issue.

3. Students may say they would assign environmental issues to writers and reporters who have ascience background, directing writers and reporters to seek many sources of scientific informa-tion, and having scientists review materials for accuracy before they are reported to the public.


Review

1. They saw the costs as being too great and saw no immediate benefit to themselves. The compa-nies could in some cases be forced to close down, and employees could lose their jobs.

2. The approach is to offer incentives for businesses to comply through the trading of emissions per-mits, which overpolluting firms will buy from underpolluting ones. The approach is supposed tocreate consensus between environmental and business interests and use market forces to solvethe problem of pollution control.

3. The air belongs to everyone. Clean air and air pollution should not become items to be traded forprofit. The approach may not be effective, may not reduce pollution significantly, may make itworse in some areas, and may further disempower average people.

4. Hidden costs show up in the use of resources and consumer prices. Examples include adding onfees for excessive disposal services and allowing hidden costs to affect the pricing of utilities.

Decisions

1. Responses will vary. Either position may be argued, but the arguments should be logical and rea-sonably well supported.

2. Responses will vary. Directors of utilities would probably favor the practice because it allowsthem more time to comply and may be a source of extra profit. Those living near an industrybuying credits might be opposed unless they were eager for the jobs and revenues created by theindustry. Those living near an industry selling credits would probably be in favor.


Review

1. Toxic gases produce symptoms of poisoning and damage the circulatory system. Tars can causecancer. Nicotine raises blood pressure and can cause circulatory problems. Tobacco particles cancause emphysema.

2. Mainstream smoke is inhaled and exhaled by a smoker. Sidestream smoke is released directlyinto the air from the burning tip of a cigarette.

3. Mainstream and sidestream smoke inhaled by “passive” smokers cause the same kinds of health


problems as smoking itself. Studies have revealed higher mortality and cancer rates among non-smokers who live or work with smokers. The children of smokers are also affected negatively.

4. Laws have been passed that require separate smoking areas in restaurants and ban smoking onairplanes and in public and state buildings. Many companies have separate smoking areas; somedo not permit smoking at all and may even refuse to hire smokers.

Decisions

1. Accept all logical responses. Many students may opt for some degree of legislation to limit smoking.

2. Students should recognize that limiting smoking is controlling a behavior that has always beenconsidered a personal choice and a private right. Protecting the health of nonsmokers must bebalanced against that of protecting personal choices and freedoms.

3. Responses will vary. Some students may feel that society has a right to limit behavior that isharmful to the individual engaged in it. Others may feel that society has no such right, at leastwhere adults are concerned.

4. Accept all reasonable responses. Issues of responsibility and rights should be addressed. Some stu-dents will oppose legislated control of behavior that takes place within the privacy of the home.Others may feel that some degree of control is justified, given the risk to children.


Review

1. The ESA intended to identify and revive endangered plants and animals in the United States. Itdid not achieve its goals because the process of listing endangered species was too lengthy andrecovery plans for listing species set futile population goals.

2. The preservation of entire ecosystems keeps the habitat of many species intact, preventing speciesfrom becoming endangered in the first place.

3. The National Biological Survey, conducted by scientists and volunteers, will inventory plant andanimal species in the United States to identify healthy ecosystems that can be permanently pre-served, thus preventing species in those ecosystems from becoming endangered.

4. Landowners fear the possible intrusion of surveyors on their property. They also fear that ifendangered species are found, development on their land would be prohibited and decrease thevalue of their property. Developers are concerned that they will make fewer profits if they areprohibited from building in certain areas.

5. The plan allows for limited development in the gnatcatcher’s ecosystem, leaving a portion of thehabitat untouched.

Decisions

1. Responses will vary. Thoughtful answers may side with developers, environmentalists, or mayreach a compromise.

2. Responses will vary. Accept all thoughtful answers.

3. Responses will vary. Accept all thoughtful answers.


Review

1. The project was intended to provide a financial incentive to recycle garbage and reduce wastegeneration.


2. Customers are charged for the amount of waste they dispose of. Separate charges could be estab-lished for different sized cans, or waste could be rated by weight or by number of bags.

3. Yes. The amount of materials people are recycling and the amount of wastes being diverted fromlandfills have increased.

4. Making new goods from recycled materials requires less energy than making them from rawmaterials.

5. These programs are difficult to organize and expensive to initiate. They may cause customerinconvenience. Infrequent collection can cause insect and odor problems. They may encourageillegal dumping and backyard burning.

Decisions

1. Accept all logical responses. Students might say that state or local governments should encouragerecycling efforts, not the federal government. Recycling programs might be more efficient if theyare managed on a smaller scale. Others might say that the federal government must be involvedto ensure that all communities are recycling.

2. Answers will vary depending on how students feel about mandatory environmental regulations.

3. Students should recognize that a commingling program would probably be more expensive andwould not provide consumers with significant incentive to reduce waste generation, although theprospect of increased taxes to pay city workers might serve as an incentive. Some students mightsay that such a program would be more effective than a pay-as-you-throw program because allrecyclables would be assured removal from the trash. Other students might say that a commin-gling program would be less effective because of the large volume of trash that workers wouldhave to sort through. Students will support or reject a commingling program depending on theirviews of its cost and effectiveness.

Issue and decisions 24

Review

1. A PAC is a nonpartisan group that represents a special interest and operates a fund that con-tributes to campaigns of various political candidates. These contributions may help a candidatewith similar interests to get elected or may convince a candidate to vote a particular way.

2. Lobbying serves as a source of information for members of Congress. It also gives political repre-sentation to groups that cannot represent themselves, such as animals.

3. Some people feel that lobbying, specifically when contributions are involved, is a form of bribery.The special interest groups do not always represent the views of the general public and mighthurt the democratic process.

4. Lobbying is protected under the First Amendment, which guarantees the right to petition Con-gress about the concerns of special interest groups and other associations.

5. Lobbying by some power plants prevented a bill from being passed that would reduce the sulfurdioxide and nitrous oxide emissions that cause acid rain. Environmental groups influenced theClimate Change Action Plan, although other groups kept it from being mandatory. The autoindustry has kept fuel efficiency in cars from being regulated. Lobbying by environmental groupsand property rights advocates will undoubtedly play a role in the reauthorization of the Endan-gered Species Act.

Decisions

1. Answers will vary.

2. Answers will vary. Students should discuss the possible effects of a lobbying prohibition on thelaw-making process.



Review

1. Risk assessment provides lawmakers with information that allows them to make decisionsregarding public health.

2. Risks to human health are determined by conducting tests, either on laboratory animals exposedto the questionable hazard or by drawing analogies to studies of similar situations.

3. Risks are difficult to determine and can be inaccurate, since scientists must extrapolate from labo-ratory tests with different exposures on different animals. Risk assessment is expensive, and thedecisions made on the basis of the assessment can also be costly. The public may also be unneces-sarily frightened about some health risks.

4. The studies on radon in drinking water used the horizontal approach. The studies used thebehavior of xenon to arrive at estimates of radon-related deaths.

5. Since an estimated 192 deaths from lung cancer per year are due to overexposure to radon indrinking water, the EPA estimates that the limits will reduce these deaths to 107 per year. It willcost the government $272 million per year.

Decisions



3. Responses will vary. Students may suggest data bases or conventions to exchange information,which may or may not lead to more accurate risk assessment.


Documents

issues/case studies - Henriksen Science · 8/1/2011 · tions shaped Earth long before humans evolved. These powerful natural events can cause immense destruction, and humans have