Cycles of Matter in an Ecosystem

the ways in which and element-or compound such as water- moves between its various living and non-living forms and locations in the biosphere

biogeochemical cycle

involving gaseous materials such as oxygen, nitrogen and carbon dioxide

volatile cycles

materials such as phosphorous are transferred through the ecosystem in sedimentary cycles

non-volatile cycle

what are the 2 types of reservoirs

non-biological reservoirs and biological reservoirs (are the living organisms)

non-biological reservoirs include?

include air (atmosphere), water (hydrosphere) and soil (lithosphere)

2 types of pathways

biological process and physical processes

e.g absorption of nutrients by roots of plants or by aquatic organisms

biological processes

e.g removal of nutrients from land to aquatic bodies by erosion and expulsion of gases during volcanic eruptions

physical processes

the rate of movement of nutrients between two reservoirs along biological and physical pathways

flow rate or flux rate

period of time for which a nutrient stays withing a reservoir

residence time

• is a key ingredient of living tissue

• is a basic constituent of all organic compounds and is involved in the fixation of energy via photosynthesis

carbon

major reservoirs of carbon:

is the pivotal molecules in the carbon cycle

carbon dioxide

carbon dioxide is released into atmosphere by:

• volcanic activity

• respiration

• human activities

• the decomposition of organic matter

carbon moves between organisms and atmosphere as a consequences of two reciprocal biological processes:

photosynthesis and respiration

what is physical pump

• driven mainly by autotrophic phytoplankton

• photosynthesis is the initial method of bringing carbon into the biological pump

• carbon stays in the food web or released from the food web in the form of defecation or dead tissues

• tiny pieces of carbon-rich material sink under the force of gravity (marine snow)

biological pump

what is carbonate pump

complex mixture of carbon compounds and humic substances

is needed to build the most vital macromolecule of life- proteins and nucleic acids and forms the porphyrin rings of chlorophyll and hemoglobin
- most frequently deficient nutrient in crop production

nitrogen (nitrogen cycle)

are capable of converting (N2) into ammonia (NH3) and ammonium (NH4+)

was the major source of soil nitrogen until recent times when the burning of fossil fuels became a major source of atmospheric deposition

atmospheric sources of soil nitrogen: lightning

• nitrogen oxides come from a variety of combustion sources that use fossil fuels

are essential to the nitrogen cycle

the most important source of fixed N is?