* Discuss how humans impact each cycle.
* Give specific examples of each cycle and how humans impact these cycles.
Carbon dioxide is slightly soluble and is absorbed into bodies of water such as the ocean and lakes. It is not overly soluble as evidenced by what happens when a can of carbonated soda such as Coke is opened. Some of the dissolved carbon dioxide remains in the water, the warmer the water the less carbon dioxide remains in the water. Some carbon dioxide is used by algae and phytoplankton through the process of photosynthesis. In the natural carbon cycle, there are two main processes which occur:
* Photosynthesis = plants use carbon dioxide and produce oxygen.
* Metabolism = oxygen is used and carbon dioxide is a product
Humans impact the carbon cycle during the combustion of any type of fossil fuel, which may include oil, coal, or natural gas. Fossil Fuels were formed very long ago from plant or animal remains that were buried, compressed, and transformed into oil, coal, or natural gas. The carbon is said to be "fixed" in place and is essentially locked out of the natural carbon cycle (www.koshland-science-museum.org). Humans intervene during by burning the fossil fuels. During combustion in the presence of air, carbon dioxide and water molecules are released into the atmosphere.
Phosphorus enters the environment from rocks or deposits laid down on the earth many years ago. The phosphate rock is commercially available form is called apatite. Other deposits may be from fossilized bone or bird droppings called guano. Weathering and erosion of rocks gradually releases phosphorus as phosphate ions which are soluble in water. Land plants need phosphate as a fertilizer or nutrient.
Humans affect the phosphorus cycle by moving phosphorus around and it becomes runoff. When it is in run-off, it can end up in large stores of water and the phosphorous can cause eutrophication to occur and this can kill animals and plants in the water. In...