A Biogeochemical Cycle is Natural processes that recycle nutrients in various chemical forms from the environment, to organisms, and then back to the environment. Examples are the carbon, oxygen, nitrogen, phosphorus, and hydrologic cycles.

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Biogeochemical cycle is the natural processes that recycle nutrients in various chemical forms from the Nonliving environment to living organisms and then back to the Nonliving environment. Examples include the carbon, oxygen, nitrogen, phosphorus, sulfur, and hydrologic cycles.