Jessica Teller - Mini Project #2

The Carbon Cycle

The black numbers in the diagram show how much carbon is stored in the various reserviors shown in the diagram and the purple numbers show how mucfh carbon is transfered between reserviors each year. This cycle is made up of four major reserviors interconnected by pathways of exchange. The reserviors include the atmosphere, the terrestrial biosphere, the oceans and the sediments.

In the atmosphere, carbon consists mostly of the gas carbon dioxide. Carbon is taken from the atmosphere in many ways. Photosynthesis turns the carbon dioxide, in the atmosphere, into oxygen. Also, in the ocean, carbon becomes quite soluble and in places of high biological productivity, organisms convert carbon to tissues. Carbon is then released back into the atmosphere is many ways such as respiration, the decay of plant and animal matter, through combustion of organic material, burning of fossil fuels, production of cement, through volcanic eruptions, and on the ocean's surface where the water become warmer, carbon dioxide is released.

The terrestrial biosphere consists of freshwater systems and non-living organic material. Carbon is taken from and released back into the terrestrial biosphere in many ways. Living organisms, such as autotrophs and heterotrophs use carbon and release carbon as they live and feed. Most carbon leaves the biosphere through respiration. Also, the burning of biomass releases large amounts of carbon back into the atmosphere. Carbon is circulated through the biosphere through sedimentation, or the process of animal shells becoming limestone.

The oceans contain large amounts of carbon in the form of biocarbonate ion. Carbon is extremely important for controlling the pH levels in the ocean water and its reactions within water. Carbon is readily exchanging between the ocean and the atmosphere in processes known as upswelling and downswelling. Bicarbonate can combine with calcium to produce limestone, which is the largest reservior in the carbon cycle.

Reference: Carbon Cycle. Retrieved March 25, 2008 from http://en.wikipedia.org/wiki/Carbon_cycle.