The study of the interactions of organisms with one another and their physical environment

Ecology

Human Impact on the Environment

Human Impact on the Environment

How much trash do you think you throw away?

How many times a day does a person pollute the environment?

How many lakes and forests are killed by acid rain?

Pollution

Pollution is anything potentially harmful that humans add to the environment.

Pollution can drastically damage the health of ecosystems as well as the health of human beings.

Air Pollution

Mainly caused by the burning of fossil fuels.

Many forms:

- Carbon monoxide

- Nitrogen oxide

The Ozone Layer Consists of a layer of gas (O3) that is

responsible for keeping UV radiation from reaching the earth’s surface.

It is being destroyed by chlorofluorocarbons (CFC’s)

CFC’s found in coolant in refrigerators & air conditioners, and the propellant in aerosol cans.

1 chlorine molecule destroys 100,000 ozone molecules.

The Ozone Layer

Acid Rain Occurs when air

pollutants get mixed with rain in the atmosphere.

The product is sulfuric acid which is falls back to earth in rain and snow.

Pure water has a pH of 7.0 (neutral)

Normal rain has a pH of about 5.6. Acid rain has a pH below the 5.6 avg. The pH in northeast US is 3.8.

Marble surfaces exposed to acid rain develop a rough "sugary" texture because the calcite grains are loosened as the edges dissolve in the rain water. Column capital volute, Jefferson Memorial, Washington, D.C.

Acid Rain and Our Nation’s Capital

Acid Rain

NaOH

Greenhouse Effect

Caused when sunlight reflected from earth’s surface is trapped as heat by carbon dioxide gas and other greenhouse gases, including methane.

Scientists predict an average temperature increase of 1-5 degrees C by 2050.

How does this impact the environment?

ResourcesRenewable resources: Resources that

replenish themselves naturally.

Example:– Trees

Nonrenewable resources: Resources that do not

replenish themselves naturally.

Examples:– Extinct species– Fossil fuels such as oil

and gas

Trees are a renewable resource, but a forest ecosystem is nonrenewable. Why?

New trees can be planted and grown to replace those cut down, but an ecosystem involves a complex web of relationships that are established over very long periods of time.

How pollution Affects our Resources

Pollution has led to a rapid draining of fuel supplies.

The known reserves of oil and natural gas will be nearly depleted by the middle of the next century.

Fossil fuels are nonrenewable resources. Nonrenewable resources do not replenish

themselves naturally, whereas renewable resources do.

Solutions to Pollution Reduce pollution by

proper waste disposal and recycling

Conserve nonrenewable resources

Reduce consumption of natural resources

Conserve energy Curbing human

population growth

Waste disposal & Recycling Each year,

Americans generate 153 million tons of garbage. This is dumped into landfills or is burned creating air pollution.

Solutions: Recycle as much as

possible– Aluminum products– Glass containers– Office & school paper– Newspaper– Many plastic materials

Buy products that contain recycled materials

Properly dispose of toxic and hazardous materials– Household insecticides– Oven cleaners– Furniture cleaners– Oil-based paint– Motor batteries & oil

Conserving Nonrenewable Resources

Topsoil for Agriculture The world has lost ¼ of its topsoil due to erosion from clearing of trees and vegetation and cultivating crops.

Ground water (water trapped beneath the soil) Groundwater is being depleted by watering lawns, washing cars, and running fountains. It is also being polluted by poor disposal of chemical wastes.

Species are disappearing. About 1/2 of the world’s tropical rainforests have been destroyed. At this rate, most of the world’s rainforests will be gone in 40 years. It is estimated that 1/5 or more of the world’s species will become extinct, mope than a million species lost, if the rainforests are destroyed.