Biogeochemical Cycles

Definition: Biogeochemical cycles describe the continuous movement of elements like carbon, nitrogen, and water through living organisms and the physical environment.

Key Cycles:

• Water Cycle: Involves processes like evaporation, condensation, precipitation, and transpiration. Maintains water balance in ecosystems.

• Carbon Cycle: Carbon moves between the atmosphere, organisms, oceans, and sediments. Key processes include photosynthesis, respiration, and fossil fuel combustion.

• Nitrogen Cycle: Nitrogen is converted between atmospheric nitrogen, nitrates, nitrites, and ammonium through nitrogen fixation, nitrification, and denitrification.

Diagram Examples:

• Carbon Cycle: Depicts movement of carbon through photosynthesis, respiration, decomposition, and combustion.

• Nitrogen Cycle: Shows nitrogen fixation by bacteria, nitrification, uptake by plants, and eventual return to the atmosphere.