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Food ResourcesFeeding the
World
InstructionsYou will need to answer each question on your copy of the PowerPoint provided. Each question is in an orange box. There are 21 questions for this section. You may add extra paper if necessary. You will only be allowed to use your written answers to the questions on the January 27 quiz.
Save yourself time and do not write complete sentences. Some of the questions you should be able to answer without using the resource link.
Look for the following symbol to click to find answers to the questions:
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FOOD SECURITY AND NUTRITION
One of six people in developing countries One of six people in developing countries cannot grow or buy the food they need.cannot grow or buy the food they need.
Others cannot meet their basic energy needs Others cannot meet their basic energy needs (undernutrition / hunger) or protein and key (undernutrition / hunger) or protein and key nutrients (malnutrition).nutrients (malnutrition).
FOOD SECURITY AND NUTRITION
The root cause of hunger and malnutrition is poverty. Chronic hunger (undernutrition) means not enough calories
to be healthy vs. malnourished which means they get the calories, but diet lacks the correct balance of proteins, carbohydrates, vitamins and minerals
Food security means that every person in a given area has daily access to enough nutritious food to have an active and healthy life.Need large amounts of macronutrients (protein,
carbohydrates, and fats).Need smaller amounts of micronutrients (vitamins such
as A,C, and E).
Even when people have access to sufficient food, a deficit in just one essential vitamin or mineral can have drastic consequences.
What is vitamin A and what does it do? What foods contain vitamin A? What happens if you do not get enough vitamin A or if
you get too much vitamin A?
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Solutions: Reducing Childhood Deaths from Hunger and Malnutrition
There are several ways to reduce childhood deaths from nutrition-related causes:Immunize children.Encourage breast-feeding.Prevent dehydration from
diarrhea.Prevent blindness from vitamin
A deficiency.Provide family planning.Increase education for women.
In the twentieth century, farming became more mechanized, and the use of fossil fuel energy increased. These changes have led to increasing food output as well
as a variety of environmental impacts. Industrial agriculture, or agribusiness, applies the techniques of the
Industrial Revolution-mechanization and standardization-to the production of food.
Describe the environmental impacts of the Green Revolution.Click
Deforestation of tropical rainforest to make room
for cash crops
The number one use of water worldwide is for agriculture
What is an aquifer?Click
The Ogallala Aquifer((pronounced OH-GA-LA-LA)
What are the effects of groundwater depletion?Click
Click
How much of the irrigated farmland in the U.S. gets water from the Ogallala?
What percent is predicted to be
depleted by 2060? Recharge rate is about 0.5 inches
per year
ClickDescribe the
agricultural issues with waterlogging.
Can you see the salt crystals?
What is soil salinization? How does salty soils interfere with plant growth? Where does the salt come from? Why is soil salinization
more of a problem in arid or semi-arid regions?Click
Compare and contrast synthetic fertilizer with organic fertilizer as they relate to the following:
source of NPK, advantages, disadvantages, cost, and nutrient distribution.
Click
Synthetic – Ammonium Nitrate Fertilizer
Organic Fertilizer
PROTECTING FOOD RESOURCES: PEST MANAGEMENT
• Organisms found in nature (such as spiders) control populations of most pest species as part of the earth’s free ecological services.
PROTECTING FOOD RESOURCES: PEST MANAGEMENT
• We use chemicals to repel or kill pest organisms as plants have done for millions of years.
• Chemists have developed hundreds of chemicals (pesticides) that can kill or repel pests.– Pesticides vary in their persistence.– Each year > 250,000 people in the U.S. become
ill from household pesticides.
Type of PesticideType of Pesticide ExamplesExamples Biomagnified?Biomagnified?
Chlorinated Chlorinated hydrocarbonshydrocarbons
DDTDDT, dieldrin, , dieldrin, chlordanechlordane
YesYes
organophosphatesorganophosphates Malathion, parathion, Malathion, parathion, diazinondiazinon
NoNo
BotanicalsBotanicals Rotenone, camphorRotenone, camphor NoNo
Contact HerbicidesContact Herbicides ParaquatParaquat NoNo
Systemic HerbicidesSystemic Herbicides 2,4-D, Roundup2,4-D, Roundup NoNo
FungicideFungicide Methyl bromideMethyl bromide NoNo
FumigantFumigant Carbon tetrachloride, Carbon tetrachloride, ethylene dibromideethylene dibromide
YesYes
Major Types of Pesticides
Bioaccumulation
Click
What were the four advantages for using
DDT?
Differentiate between bioaccumulation and
biomagnification.
Bioaccumulation describes the way pollutants enter an ecosystem. Many human activities, such as pesticide use and coal-burning, introduce such harmful substances as DDT, methylmercury and other organic chemicals into the environment. These substances are collectively known as Persistent Bioaccumulative Toxic substances, or PBTs. Bioaccumulation occurs when a PBT enters an organism—through breathing, ingestion, or skin contact—more quickly than the substance can leave the organism. The organism now has a higher concentration of the substance than the surrounding environment. Source: http://www.ehow.com/list_5890741_effects-bioaccumulation-ecosystem.html
PROTECTING FOOD RESOURCES: PEST MANAGEMENT
Which disadvantage do you think is the worse? Explain.
Superpests
Explain the connection between Roundup and pig weed.
Click
Pig weed
Additional Examples of Superpests
Pesticide-resistant kudzu beetle causing problems in south Georgia
by eating our soybean crops
Stink bugs in California – resistant to pesticides (people use shovels to
remove them from around their homes
What is a pesticide treadmill?
Click
The ideal Pesticide
• The ideal pest-killing chemical has these qualities:– Kill only target pest.– Not cause genetic resistance in the target
organism.– Disappear or break down into harmless
chemicals after doing its job.– Be more cost-effective than doing nothing.
Pesticides Kill Natural Pest Enemies and Create New Pests
• Broad-spectrum pesticides kill natural predators
• New pests are unleashed once natural predators eliminated
• Currently 100 of the 300 most destructive insect pests in the U.S. were secondary pests
Where do pesticides go?
• Bottom sediments
• Surface water
• Groundwater
• Air
• Food
• Humans
• Wildlife
Each Year in the United States Pesticides Applied to Cropland
• Wipe out 20% of the U.S. honeybee colonies and damages another 15%
• Kill more than 67 million birds
• Kill 6 – 14 million fish (runoff from croplands)
• Menace about 20% of the endangered and threatened species in the U.S.
Endocrine DisruptorsWhat are endocrine disruptors?
What are sources of endocrine disruptors?
How can endocrine disruptors affect my health?
Click
This sturgeon shows both male and female reproductive organs
Pesticide Protection Laws in the U.S.
– The Environmental Protection Agency (EPA), the Department of Agriculture (USDA), and the Food and Drug Administration (FDA) regulate the sales of pesticides under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA).
– The EPA has only evaluated the health effects of 10% of the active ingredients of all pesticides.
Other Ways to Control Pests
• There are cultivation, biological, and ecological alternatives to conventional chemical pesticides.– Fool the pest through cultivation practices.– Provide homes for the pest enemies.– Implant genetic resistance.– Bring in natural enemies.– Use pheromones to lure pests into traps.– Use hormones to disrupt life cycles.
Other Ways to Control Pests
Biological pest control
Wasp parasitizing a gypsy moth
caterpillar. She will then lay her eggs inside caterpillar and when babies
hatch they eat their way out
Advantages of Biological Control
• Focuses on selected target species
• Is nontoxic to other species
• Can be self-perpetuating
• Minimizes genetic resistance
Disadvantages of Biological Control Agents
• Can take years of research
• Cannot always be mass-produced
• Often are slower acting and more difficult to apply
• Must be protected from pesticides sprayed close by
• Can multiply and become pests themselves
Other Ways to Control Pests
• Genetic engineering can be used to develop pest and disease resistant crop strains.
Both tomato plants were exposed to Both tomato plants were exposed to destructive caterpillars. The genetically destructive caterpillars. The genetically altered plant (right) shows little damage.altered plant (right) shows little damage.
Integrated Pest Management (IPM)
Define IPM.
How do farmers implement IPM to control pest species?
When will the farmers use chemicals if they are using IPM? Why?
Why is it important to understand the pest life cycle?
Click
Which of the following practices is NOT part of integrated pest management?
A.Crop rotationB.Elimination of pesticidesC.Use of pest-resistant cropsD.Introduction of predatorsE.Frequent inspection of crops
Industrial Food Production: High Input Monocultures
Livestock production in developed countries is industrialized:Feedlots are used to fatten up cattle before
slaughter.Most pigs and chickens live in densely populated
pens or cages.Most livestock are fed grain grown on cropland.Systems use a lot of energy and water and
produce huge amounts of animal waste.
PRODUCING MORE MEAT
About half of the world’s meat is produced by livestock grazing on grass.
The other half is produced under factory-like conditions (feedlots).Densely packed livestock are fed grain or fish
meal.Eating more chicken and farm-raised fish
and less beef and pork reduces harmful environmental impacts of meat production.
PRODUCING MORE MEAT
Which animal is cheaper to raise
and has less impact on the environment?
List in order from requiring most feed to least feed to produce a pound of flesh: turkey, chicken, beef, fish, pork
Concentrated Animal Feeding
Operations (CAFOs)
CattleChickens
Pigs
CAFOs = Animal Feedlots
Waste Lagoon
If you eat…you must excrete.
What looks like small ants are cows
The largest cattle feedlot in Nebraska is located in Broken Bow. On 600 acres of land you will find 85,000 head of cattle.
How many cattle is that per acre? Remember the front lawn of Milton is
about one acre.
Describe the following pollutants produced by CAFOs: pathogens, pharmaceuticals, excessive nutrients, and
harmful gases.
Click
The effluent here is hog waste
Below – hog waste spills from busted dam
on waste lagoon
The waste from these lagoons are sprayed on
the fields of bermuda hay as a natural
fertilizer
Trade-Offs
Animal Feedlots
Advantages Disadvantages
Increased meat production
Need large inputs of grain, fish meal, water, and fossil fuelsHigher profits
Concentrate animal wastes that can pollute water
Less land use
Reduced overgrazing
Reduced soil erosion
Antibiotics can increase genetic resistance to microbes in humans
Help protect biodiversity
Which single advantage and
which single disadvantage do you think are the most important?
Support your answer.
More sustainable animal farmingNot all meat comes from CAFOs. Free-range chicken and beef are becoming more popular in the U.S. Free-range meat, if properly produced, is more likely to be sustainable than meat produced in CAFOs. Because the animals are not as likely to spread disease as when they are kept in close quarters, the use of antibiotics and other medications can be reduced or eliminated. The animals graze or feed on the natural productivity of the land so less fossil fuel goes into the raising of free-range meat. The manure and urine are dispersed over the range area where it is naturally processed by detritivores and decomposers in the soil.
Compare and contrast free-range cattle with cattle from a feedlot.
Biodiversity Loss Soil Water Air Pollution Human Health Loss and degradation of grasslands, forests, and wetlands
Erosion Water waste Greenhouse gas emissions from fossil fuel use
Nitrates in drinking water
Loss of fertility Aquifer depletion
Pesticide residues in drinking water, food, and air
Salinization Increased runoff and flooding from cleared land
Other air pollutants from fossil fuel use
Fish kills from pesticide runoff
Waterlogging
Sediment pollution from erosion Greenhouse gas
emissions of nitrous oxide from use of inorganic fertilizers
Contamination of drinking and swimming water with disease organisms from livestock wastes
Desertification
Killing wild predators to protect livestock
Fish kills from pesticide runoff
Surface and groundwater pollution from pesticides and fertilizers Belching of the
greenhouse gas methane by cattle
Loss of genetic diversity of wild crop strains replaced by monoculture strains
Bacterial contamination of meat
Overfertilization of lakes and rivers from runoff of fertilizers, livestock wastes, and food processing wastes
Pollution from pesticide sprays
THE GENE REVOLUTION
To increase crop yields, we can mix the genes of similar types of organisms and mix the genes of different organisms.Artificial selection has been used for centuries to
develop genetically improved varieties of crops.Genetic engineering develops improved strains
at an exponential pace compared to artificial selection.
Controversy has arisen over the use of genetically modified food (GMF).
Mixing Genes
Genetic engineering involves splicing a gene from one species and transplanting the DNA into another species.
Genetically modified organisms (GMO) refers to plants or crops that have been modified using molecular biology techniques. These
plants are modified in labs or research centers with the intention of enhancing its desired traits such as pest resistance, enhancing nutrition, etc. There are natural methods of doing this however; genetic modification ensures that it can be done precisely and
quickly. In addition to plants, now animals are also being genetically engineered.
Describe the following benefits of GMOs: pest resistance,
tolerance to herbicides, resistance to disease and cold,
tolerance to drought and salinity, enhancing nutritional
content, and remedy for environmental pollution.
Click
Click
Describe the risks and controversies of the use of GMOs. Explain the connection between Bt
corn and monarch butterflies.
Which fish do you think has been genetically modified?
What do we really know about GMOs?
THE GENE REVOLUTION
The winged bean, a GMF, could be grown to help reduce malnutrition and the use of large amounts of inorganic fertilizers.
THE GENE REVOLUTION Controversy has arisen over the use of genetically
modified food (GMF).Critics fear that we know too little about the long-term
potential harm to human and ecosystem health. There is controversy over legal ownership of genetically
modified crop varieties and whether GMFs should be labeled.
Click
Fish is the third major source of food for humans, after grain and meat. In many coastal areas, particularly in Asia and Africa, fish accounts for nearly all of the animal protein that some people consume.
A study in 2006 found that 30% of fisheries worldwide had experienced a 90% decline in fish populations. The decline of a fish population by 90% or more is referred to as a fishery collapse.
Why have we seen an increase in ocean harvests
over the past 50 years? (four factors)
CATCHING AND RAISING MORE FISH AND SHELLFISH
Government subsidies given to the fishing industry are a major cause of overfishing.Global fishing industry spends about $25 billion
per year more than its catch is worth.Without subsidies many fishing fleets would have
to go out of business.Subsidies allow excess fishing with some
keeping their jobs longer with making less money.
Overfishing and Extinction: Gone Fishing, Fish Gone
About 75% of the world’s commercially valuable marine fish species are over fished or fished near their sustainable limits.Big fish are becoming scarce.Smaller fish are next.We throw away 30% of the fish we catch.We needlessly kill sea mammals and birds.
Sustainable Fisheries Act (1996)• Focus shifted fisheries management from a
focus on economic sustainability to a species-sustainability approach
• Protection of critical marine habitat – important for both commercial fish species and non-target species
• No fishing until populations recover
Aquaculture: Aquatic FeedlotsRaising large numbers of fish and shellfish
in ponds and cages is world’s fastest growing type of food production.
Fish farming involves cultivating fish in a controlled environment and harvesting them in captivity.
Catfish aquaculture in Mississippi
What happens to the fish and the fish “poo” if the river
floods?
Open ocean aquaculture
Closed-circulation aquaculture
Two types of floating cages for aquaculture
There are many environmental
problems associated with aquaculture. Excess fish waste
causing algal blooms is just one of those
environmental issues.
Environmental Risks of Marine Aquaculture
• Escape of non-native species– Genetically modified organisms
• New diseases and parasites– Sea lice on farm-raised salmon
• Drugs– Antibiotics, hormones used on fish
• Heavy metals– Found in fish meal used for food
• Fish sewage– Unwanted algae problems– Hypoxic zones (dead zones)
Trade-Offs
Aquaculture
Advantages Disadvantages
High efficiency Needs large inputs of land, feed, and water
High yield in small volume of water
Large waste output
Destroys mangrove forests and estuaries
Can reduce overharvesting of conventional fisheries Uses grain to feed
some species
Low fuel use Dense populations vulnerable to disease
Tanks too contaminated to use after about 5 years
High profits
Profits not tied to price of oil
Which of the following disadvantages do you think is
the worse? Explain.
