Biogeochemical Cycle

What is Biogeochemical Cycle?

In geography and Earth science, a biogeochemical cycle or substance turnover or cycling of substances is a pathway by which a chemical element or molecule moves through both biotic (biosphere) and abiotic (lithosphere, atmosphere, and hydrosphere) compartments of Earth. A cycle is a series of change which comes back to the starting point and which can be repeated.

The term “biogeochemical” tells us that biological, geological and chemical factors are all involved. The circulation of chemical nutrients like carbon, oxygen, nitrogen, phosphorus, calcium, and water etc. through the biological and physical world are known as biogeochemical cycles. In effect, the element is recycled, although in some cycles there may be places (called reservoirs) where the element is accumulated or held for a long period of time (such as an ocean or lake for water).

Water, for example, is always recycled through the water cycle, as shown in the diagram. The water undergoes evaporation, condensation, and precipitation, falling back to Earth clean and fresh. Elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another through biogeochemical cycles.

What are the roles of biogeochemical cycles in environment?

An ecosystem is one through which "energy flows and matter recycles". So, biogeochemical cycles keep the ecosystem running. Biogeochemical cycles (or processes), from agriculture point of view, generate CO2, CH4 and N2O gases, three most important GHGs affecting global warming. Therefore, biogeochemical cycles do affect environment directly. They are the essential drivers of environmental processes as they regulate the levels of elements essential for life among different pools. Alterations in biogeochemical cycles, such as human induced rapid increase of the concentration of certain elements in the atmosphere, may change the proportion of these elements in...