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Human Impact on EcosystemsChapter 6 Day 12Human Ecological Footprint Map

Humans have influenced 83% of Earths surface based on population, travel routes, land use, and lightsEcological footprint is the measurement of how much land, water and natural resources a person, city, country or humanity as a whole requires to produce the resource it consumesTo the Teacher: Review and discuss with students.Does this number seem like a lot or a little? Answers will vary, but remind students that 83% is just over 4/5 of Earth surface. Some areas are more vulnerable to human influence than others, why might this be? Areas that are highly vulnerable are those that are easily accessible to humans and/or those that can supply natural resources that are in demand.Predict how future human population growth could affect the environment. Accept all reasonable answers. Sample answer: It could lead to an increases human demand for water, food, and land, and thus leave fewer resources for other species.To the Teacher: Tell students that Americans make up 5% of the worlds population. However, Americans own 30% of the worlds cars and consume 25% of the worlds energy.Why do different cultures use and consume things at different rates? What do these numbers indicate about contemporary American culture? Possible answers: Answers will vary, but encourage students to make a connection to variables such as average lifespan; income; access to goods; diet; culture; climate.The United States uses more resources and produces more waste than an other country. How is this resource use reflected in the ecological footprint of the united States? The United States ecological footprint is the largest in the world.Is it possible to have no ecological footprint? To leave no footprint would mean that a person replaces to the environment exactly what he takes. Since the mid-1980s, humankind has been in ecological overshoot, meaning they are taking more than they are giving back.

3What is an environmentally sustainable society?An environmentally sustainable society meets the basic resources of its people without degrading or depleting the natural capital that supplies these resources.Imagine you win $1 million dollars in the lottery.

Natural Capital= Natural RESOURCES + Natural SERVICESTo the Teacher: Tell students to imagine they have won a million dollars in the lottery. Ask them what they would do with their money. Accept all reasonable answers.Propose that they do not touch the money at all, but invest this money at 10% interest per year, and they will have a sustainable annual income of $100,000 without depleting your capital. Wait for their reaction and accept all reasonable arguments for and against.If you spend $200,000, your $1 million will be gone early in the 7th year.If you spend $110,000 a year, you will be bankrupt early in the 18th year.Introduce the verb sustain as the ability to maintain a lifestyle without losing ones wealth, living within your means.Tell students that the word sustain comes from the Latin words sub- which means below, and tenere, which means to hold. Ask them how these meanings relate to the term sustainable development. Sustainable development is development that holds or maintains the use of resources at or below the level that allows them to replenish or survive.Ask students to explain what they think an environmentally sustainable society is. Accept all reasonable answers.Discuss with students what they would consider to be a basic resource.Basic resources: Clean water, clean air, shelter, food. Natural capital: Planets air, water, soil, wildlife, minerals, energy resources, etc.

4Is it a necessity to live in an environmentally sustainable society?Humans use the equivalent of 1.5 planets to provide the resources we use and absorb our waste. By 2030 well need two Earthsto support us.We are turning resources into waste faster than waste can beturned back into resources. Puts us in global ecological overshoot, depleting the very resources on which human life and biodiversity depend.

To the Teacher:Explain to students that it now takes the Earth one year and six months to regenerate what we use in a year. Examples of our struggling planet is all around us: collapsing fisheries, diminishing forest cover, depletion of fresh water systems, and the build up of carbon dioxide emissions, which creates problems like global climate change.Tell students that it is abundantly clear that Earths human carrying capacity has exceeded many earlier predictions. How has technology affected human population growth? Technology has improved human health and survival; made agriculture more intensive and productive; increased the speed of construction of living spaces, production of tools, equipment, and clothing; and has provided heating, air conditioning, plumbing sanitation, water purification, transportation, and many other things that have allowed the human population to grow at an exponential rate.

5Think About ItWhat does renew mean?What does renewable mean?What does nonrenewable mean?What does resource mean?What is a renewable resource?What is a nonrenewable resource?

To the Teacher:Discuss with your students the following questions.After establishing the meaning of renewable and nonrenewable, ask them to identify some of the examples in the image.Renewable energy is energy which is generated from natural sources i.e. sun, wind, rain, tides and can be generated again and again as and when required. They are available in plenty and by far most the cleanest sources of energy available on this planet. For e.g.: Energy that we receive from the sun can be used to generate electricity. Similarly, energy from wind, geothermal, biomass from plants, tides can be used this form of energy to another form.Non-Renewable energy is energy which is taken from the sources that are available on the earth in limited quantity and will vanish fifty-sixty years from now. Non-renewable sources are not environmental friendly and can have serious affect on our health. They are called non-renewable because they cannot be re-generated within a short span of time.6What are the types of resources?A resource is anything obtained from the environment to meet our needs and wants.Renewable: Resources that can be replenished through natural processes (water cycle, trees, and others)Nonrenewable: Exist in a fixed quantity (fossil fuels, minerals)Resources renewed by natural processes are sustainable if we do not use them faster than they are replenished.Sustainable yield is the highest rate at which a renewable resource can be used indefinitely.Environmental degradation occurs when we exceed a renewable resources natural replacement rateTo the Teacher:Encourage students to use Power Notes.

7Energy Resources SourcesRenewable Energy SourcesSolar EnergyWind EnergyBiofuelHydropowerGeothermalNon-Renewable Energy SourcesFossil FuelsCoalNatural GasOilWhere do pollutants come from andwhat are their effect?Pollutants are chemicals that cause harm to people or other organisms.Natural (volcanic eruptions)Anthropogenic (burning fossil fuels)Pollutant have three types of unwanted effectsDisrupt or degrade life-support systemsDamage wildlife, human health, and propertyNuisance

9What are some causes of environmental problems?Rapid population growthUnsustainable resource usePovertyNot including the environmental costs of economic goods and servicesin their market pricesTo the Teacher: 10Human Impact on EcosystemsTopic 5 Day 211What are the key environmental problems?12Biodiversity DepletionHabitat destructionDeforestationUrbanization Land developmentHabitat degradationResource extractionwaste dumpingSpecies IntroductionsExtinctionExtinction rate is up to 30,000 species per year.That's three per hour!!!

16Water PollutionAcid rain from soluble, acidic atmosphere gases Bio magnification- increasing accumulation of toxic chemicals up the trophic levelsOil SpillsAlgal blooms from eutrophicationNutrient overload in a water sourceCauses decreased oxygen levels in water

17Food Supply ProblemsOvergrazingWetland loss and degradationOverfishingCoastal pollutionSoil erosionWater shortagesGroundwater depletionPoor nutrition

18Food Supply Problems: BiomagnificationBiomagnification:The accumulated build up of harmful toxins as energy is transferred up through a food chain.Example: Mercury levels in aquatic organismsThe organisms MOST affected are those at the top of the food chainWho could that be???

1 ppm3 ppm4 ppm4.75 ppm5.3 ppmWaste ProductionSolid wasteHazardous wasteLandfills

21Soil PollutionUse of fertilizers and pesticides has many environmentally harmful effectsFertilizers in the soil erode into water supply and cause Algal bloomsResults in oxygen depletion of aquatic ecosystemsPesticides can cause health issues to organisms and to humansDeforestation and agricultural developmentLand and soil degradationErosion via run-offdesertification