Outline the salients features of carbon cycling in an ecosystem .

Explanation

All living organisms require nutrient elements in relatively large amounts . They get the nutrients from the biosphere components . The nutrients elements derived from the earth by the living organisms for use in their growth and metabolism are called boigeochemicals or biogenetic nutrients . The movement of nutrient elements through the living and the nonliving components of the biosxphere is called biogeochemical cycle .
In the gaseous cycles the reservoir for nutrient elements is in the atmosphere . The four most abundant elements in the living systems H, C,O, N - have predominantly gaseous cycles . The carbon cycle is quick and relatively perfect system in that the elements remain in circulation . Carbon is generally considered as the basis of life . Carbon atom is acting as a back bone for complex organic molecules like carbohydrates , lipids , proteins and nucleic acids .
The main sources of carbon are air , water , fossil fuel and rocks .
Carbon dioxide is obtained from the biosphere by
i. green plants for photosynthesis
ii. corals for making calcareous skeletons .
Carbon is added to the biosphere by
i . respiration in organisms .
ii. decay of organic wastes and dead organisms .
iii. burning of fuel .
iv. weathering of rocks
v. volcanic activity .