Matter moves between ecosystems, biotic & abiotic environments, and organisms, unlike energy
Biogeochemical cycling involves: Biological, geologic and chemical interactions
Five major cycles: Carbon, Nitrogen, Phosphorus, Sulfur and Water (hydrologic)
Cycles of nutrients in ecosystems are called biogeochemical cycles. In the IB, we are covering these in topic 2:
carbon cycle (both SL and HL) and
nitrogen cycle (HL only).
The cycling of nutrients is essential in the maintenance of ecosystems because nutrients provide the chemical elements needed for biological molecules.
Carbon is needed for carbohydrates, fats and proteins
Nitrogen is needed for proteins
the amount and type of weathering
overland run-off and soil erosion
the amount of rainfall
rates of decomposition
the type of vegetation (woody perennial species hold onto nutrients for much longer than annuals)
the age and health of plants
plant density
fire
Carbon capture
Fossil fuels as C storage
Alleviating the effects of human activities on the carbon cycle
Measures that are required to alleviate the effects of human activities on the carbon cycle include
Low carbon technologies. These are renewable energy resources such as solar heating, air-source heat pumps, ground-source heat pumps, biomass heating, solar panels, photovoltaics (PV), and wind turbines.
Reduction in the use of fossil fuels. A reduced combustion of fossil fuels will reduce CO2 emissions.
Reduction in soil disruption. The majority of carbon in ecosystems is stored in soil, so conserving soils is an important way of reducing carbon emissions.
Reduction in deforestation. Trees are an important store and sink of carbon, so maintaining forest ecosystems maintains the equilibrium of the carbon cycle.
Carbon capture through reforestation and artificial sequestration. Carbon capture is the process of capturing CO2 and depositing it where it will not enter the atmosphere