explain why three are differences in these nutrient cycles
Answers
Answer:
, Sources and Sinks of Essential Elements
Biogeochemical cycles are pathways by which essential elements flow from the abiotic and biotic compartments of the Earth.
LEARNING OBJECTIVES
Identify sources and sinks of essential elements
KEY TAKEAWAYS
Key Points
Biogeochemical cycles are pathways by which nutrients flow between the abiotic and abiotic compartments of the Earth. The abiotic portion of the Earth includes the lithosphere (the geological component of the Earth) and the hydrosphere (the Earth’s water).
Ecosystems rely on biogeochemical cycles. Many of the nutrients that living things depend on, such as carbon, nitrogen, and phosphorous are in constant circulation.
Essential elements are often stored in reservoirs, where they can be taken out of circulation for years. For example, coal is a reservoir for carbon.
Humans can affect biogeochemical cycles. Humans extract carbon and nitrogen from the geosphere and use them for energy and fertilizer. This has increased the amount of these elements in circulation, which has detrimental effects on ecosystems.
Key Terms
Reservoir: Reservoirs are places where essential elements are sequestered for long periods of time.
biogeochemical cycle: A pathway by which a chemical element or molecule moves through both biotic (biosphere) and abiotic (lithosphere, atmosphere, and hydropshere) compartments of the planet.
Most important substances on Earth, such as oxygen, nitrogen, and water undergo turnover or cycling through both the biotic (living) and abiotic (geological, atmospheric, and hydrologic) compartments of the Earth. Flows of nutrients from living to non-living components of the Earth are called biogeochemical cycles.