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4.3.5 carbon cycle
In nature, carbon exists in the form of inorganic and complex organic compounds. In atmosphere the concentration of CO2 is only 0.32 per cent which is less than what is required by plants for photosynthesis. The CO2 is the main source of carbon required to build the organic world. The CO2 returns back into the atmosphere through the process of respiration by all groups of organisms. The other method of returning carbon is through degradation (decomposition) of organic matter by microorganisms. A simplified carbon cycle is given in Figure. |
Last modified: Tuesday, 27 December 2011, 2:08 PM