If you were to track a single atom of an element as it moves through an ecosystem over a large period of time as it goes from living to nonliving components, you would be studying the cycle of that element.

biogeochemical cycle

Explanation:

A biogeochemical cycle is the one in which an element, molecule or compound circulate between living and non living things. It is also known as an inorganic-organic cycle. A chemical, element or molecule changes its form while moving from one biotic or abiotic component to another biotic or abiotic component. These elements in a cycle are usually converted into usable forms and then transferred from one stage to other where they remain in sink for some period of time and lastly released to the environment in their original form.

Some common biogeochemical cycles are – sulfur cycle, phosphorus cycle, nitrogen cycle etc.  

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