The carbon cycle is nature's way of reusing carbon atoms, which travel from the atmosphere into organisms in the Earth and then back into the atmosphere over and over again. Most carbon is stored in rocks and sediments, while the rest is stored in the ocean, atmosphere, and living organisms. A biogeochemical cycle is a pathway by which a chemical substance moves through both biotic and abiotic components of the earth. Biological, geological and chemical factors are all involved in pathways through which chemical nutrients like carbon, oxygen and nitrogen circulate.

Phosphorus cycle