Before revision: The forces driving biogeochemical cycles include metabolic processes within organisms, geological processes involving the earth 's mantle, as well as chemical reactions among the substances themselves, which is why these are called biogeochemical cycles.
After revision: The forces driving biogeochemical cycles include metabolic processes within organisms, geological processes involving the Earth 's mantle, as well as chemical reactions among the substances themselves, which is why these are called biogeochemical cycles.