An Overview A. Biogeochemical cycles influence the availability of essential elements in ecosystems. Elements are available to producers as ions. Nutrient reserves are maintained by environmental inputs and recycling activities. The amount of nutrients being cycled is greater than the amount entering or leaving. Environment inputs are by precipitation, metabolism, and weathering.
Outputs are by runoff and evaporation.
In the hydrologic cycle, oxygen and hydrogen move as water molecules. V. Hydrologic Cycle A. Water is moved or stored by evaporation, precipitation, retention, and transportation. B. Water moves other nutrients in or out of ecosystems. A watershed funnels rain or snow into a single river. Nutrients are absorbed by plants to prevent their loss by leaching.