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What is going on in the cartoon?

This is an example of Deforestation. As the human population grows, so does the demand for Earth’s resources

•Earth’s human carrying capacity is unknown

•Technology has helped to increase Earth’s carrying capacity.

– gas-powered farm equipment

– medical advancements – clean water – public assistance

• Over 6.6 billion people

• Many natural resources are nonrenewable – Fossil fuels take millions of

years to form

• More people means: – 1) More forests removed

– 2) More resources consumed

– 3) More CO2 released

• Nonrenewable resources are used faster than they can form or be replenished:

– Coal

– Oil

– Natural Gas

• Renewable resources cannot be used up or can replenish themselves over time :

– Wind

– Solar

– Water

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• An ecological footprint is the amount of land needed to support a person.

The land must produce and maintain enough

–food and water –shelter –energy –waste

–Several factors effect size:

–Amount/efficiency of resource used –Amount/toxicity of waste produced

Ozone Layer Depletion • Ozone Function:

Block UV radiation from sun

• Problems:

– CFCs thinning the ozone layer

– More UV radiation reaches the surface

• Effects: Crop damage, skin cancers, Eye damage

• Solution: Reduce CFCs, regrow trees

UV

Ozone layer Ozone layer

CFCs

UV

The Smog and Ground-Level Ozone • Reason:

– Burning of fossil fuels & industry

• Problems: – Respiratory illness

– Ozone gas is poisonous

• Causes: – Particulates rise into air and

react with sunlight to make air pollution

• Solutions: – Reduce use of fossil fuels

– alternative energy sources

– Plant trees

The Greenhouse Effect • G.H.E. is naturally good (it

warms Earth)

• Problem: Excess heat trapped near the earth’s surface

• Fear: Climate patterns change, ice caps melt

• Main Cause: CO2 from burning of fossil fuels (coal, oil, natural gas)

• Solutions: Reduce use of fossil fuels, regrow trees, alternative energy sources

What’s in a name?

The purpose of a greenhouse is to trap heat year round

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Earth

heat

Some heat escapes into space

Some heat naturally trapped by Earth’s atmosphere

Earth

Earth Excess CO2 in atmosphere

Less heat escapes into space

More heat trapped near Earth’s surface

The Greenhouse Effect is naturally GOOD!

Mars: No Greenhouse Effect

Little heat is trapped by the thin CO2 atmosphere. High temperatures can be around 20⁰F.

Earth: Balanced Greenhouse Effect

Average global temperature is 57⁰F.

Venus: The Extreme Greenhouse Effect

Heat is trapped by the thick CO2 atmosphere. Temperatures reach 750⁰F.

• Defined: Precipitation with a below normal pH

• Cause:

– Fossil fuel pollution rises into the air & then falls as rain

• Effect:

– Waterways more acidic

– Kills plant and animal life

• Solutions:

– Reduce fossil fuel usage

– Add buffer (base) to waterways

• Defined: pollution in water supplies

• Reasons:

– Waste

– Medicines

– Agricultural Runoff

– fertilizers

– pesticides

• Problems:

– Species lost

– Ecosystems harmed

• Indicator species

give sign of ecosystems health

ex: amphibians

• Solutions:

– Manage waste

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Biomagnification = accumulation of toxins in the food chain.

• Pollutants that are fat soluble can move up the food chain.

– These pollutants stay in the body fat of an organism

– predators eat contaminated prey

• Top consumers, including

humans, are most

affected.

Deforestation • Defined: Clearing of

forested areas

• Reasons:

– High demand for wood products

– Create farmland

• Problems:

– Species lost

– Excess CO2 released

• Solutions:

– Recycle

– Improved farming techniques

Introduced (& Invasive) Species • Defined: Foreign organisms are

introduced to a new habitat – Invasive- harms native species

• Reason:

– Pet industry, “free ride” organisms, pest control

• Effects:

– Foreign species outcompete native species

– Food webs unbalanced

– Economic damage

• Solutions:

– Laws preventing foreign goods into new countries

– Introduce predators

•The Environmental Protection

Agency (EPA)

created in 1970

Works to protect species

•Clean Water Act

•Clean Air Act

•Endangered Species Act (this recovered

the bald eagle)

Those listed are called

“Umbrella Species”

oEntire habitats protected