IV. Humans Alter the Biosphere

A. Food Production Causes Land Pollution 1. Agriculture (man-made monocultures) that must be maintained by a high energy input in fertilizers, pesticides and herbicides

2. Agro-Corporations have altered Food Production

Confined Animal Feed Operations a) Cafos are cruel to the confined animals

b) Large amounts of antibiotics are needed to keep the animals alive in such close proximity. This leads to antibiotics in meat and drug resistant bacteria.

c) Large Agro-businesses have crushed family farms

d) Huge amounts of animal excrement pollute ground water and streams

1.Existing landfills are running out of space. 2.Most communities reject plans for new landfills B. An Urban ecosystem’s largest product is trash.

3. Landfills are not just holes in the ground. a)Ground water must be monitored and protected from contamination b)Gasses must be collected or flared c)Landfills are breeding grounds for disease organisms

4. Incinerators reduce trash volume but they pollute the air. Further, the ash that remains is high in toxins.

C. Water Pollution

1. Fertilizer runoff increases Eutrophication- increase in the nutrients in waterEutrophication a)Eutrophication results in Algal Blooms (rapid increase of algae populations) Algal Blooms b)When the algae die, decomposers use up large quantities of oxygen to break them down c)Aquatic organisms die from lack of oxygen

2. Pesticide run off accumulates in the water supply resulting in Biological Magnification- the build up of toxins as you move up the food chain

3. Our Fresh Water Supply is Limited a)Of the 7 billion people on earth, 1.1 billion do not have access to safe, clean drinking water. ( b)California has about 20 years of water left in the state. Maude Barlow, author of Blue Covenant and co-author of Blue Gold, c)Water is a $400 billion dollar global industry; the third largest behind electricity and oil. CBS News.

D. Air Pollution

1. Burning Fossil fuels (oil, coal and gas) pollutes the air by releasing nitrous & sulfur oxides, particulate, hydrocarbons a)Particulates (soot) builds up and covers buildings and neighborhoods and can cause respiratory problems b)Sulfur and nitrogen oxides combined with atmospheric moisture and cause acid rainacid rain 1)Acid rain destroys forests, lakes and streams by lowering the pH 2)Few living things can tolerate a pH below 5

C. Hydrocarbons can cause the Greenhouse Effect by preventing heat from dissipating back into space

Data indicates atmospheric CO 2 has been increasing for the past 50 years

Red Indicates CO 2 Emissions

Fossil Fuels are non-renewable and highly polluting. World oil supplies could be depleted by 2050

As man clears more area for expanding cities and agriculture, wildlife, both plants and animals, lose their habitat

Loss of Habitat a)loss of feeding and breeding grounds can result in extinction b)Extinction- the elimination of a species from the biosphere forever c)If a species is endangered it is near extinction and if it is threatened it is near to being endangered endangered

2.Nearly all medicines were derived from a plant,fungus, bacteria or animal species plant 3.If we destroy many species, we may lose the genetic material we need to cure cancer or AIDS.

D. Possible Solutions 1.Natural fertilizers (garbage, manure) and crop rotation with legumes can reduce our dependence on chemical fertilizers

2. Recycling (metals, glass and paper) will reduce the speed we are using up landfill space. Garbage can be composted to provide fertilizer.

3. Alternate Energy Sources (nuclear, hydroelectric, solar, geothermal, wind, waves) can reduce our use of fossil fuel