Phosphorus cycle is one of the biogeochemical cycles (similar to water cycle, nitrogen cycle, etc.) and describes how this element moves through the various compartments of our earth. Phosphorus is a key element in energy molecules (ATP), DNA, and cell membranes, and is also required in animals and plants. Unlike other element/nutrient cycles, Phosphorus is typically a solid and hence the role of atmosphere in the cycle is minimal. Phosphorus is available from natural minerals (such as apatite), from where it is taken up by plants and minerals. The death of plants or phosphorus leaching from plant residue will be converted as organic phosphorus. Part of phosphorus may also be lost from soil due to erosion and runoff. Phosphorus movement is very slow from oceans and soil and hence is a very slow cycle.
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