University Corporation for Atmospheric Research
Ucar: Biogeochemical Cycles
The ways in which an element or compound such as water moves between its various living and nonliving forms and locations in the biosphere is called a biogeochemical cycle. All of the atoms that are building blocks of living things are a...
University of Illinois
University of Illinois Extension: Energy and Ecosystems Use Some Lose Some
Life on Earth is possible because energy flows one way through ecosystems, while matter cycles endlessly. Water and elements, such as carbon, nitrogen, phosphorous, and sulfur are examples of matter that cycles through ecosystems.