Biogeochemical Cycles
In an ecosystem, the flow of energy and flow of nutrients differ fundamentally:
- Energy flow is linear — it moves in one direction, gets utilized, and is lost as heat at each step.
- Nutrient flow is cyclical — nutrients are continuously recycled between living organisms and the physical environment.
Nutrients absorbed from the soil by green plants pass through herbivores and carnivores. When plants and animals die, the nutrients locked in their remains are released back into the soil by detritivores and decomposers. This process of recycling nutrients through biological, geological, and chemical pathways is called the:
Biogeochemical Cycle
(Bio = living, Geo = earth/rocks, Chemical = elements)
- The Earth or biosphere is a closed system for nutrients, meaning no significant amount of nutrients is imported from or exported to space. Over 40 elements are essential for the life processes of plants and animals.
Components of a Biogeochemical Cycle
Reservoir Pool:
- The long-term storage of nutrients, often in rocks, soil, or the atmosphere.
- Acts as a nutrient reserve.
Cycling Pool (Active Compartment):
- Short-term storage of nutrients in plants, animals, and microorganisms.
- Nutrients move quickly through this compartment during biological processes.