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BIO121-ch4
| Term | Definition |
|---|---|
| biomass | living matter |
| gross primary productivity (GPP) | total amount of energy fixed by autotrophs over a given period of time |
| respiration: (R) | release of energy from fuel molecules |
| net primary productivity (NPP) | amount of energy available for storage after respiration, GPP-R=NPP |
| aerobic respiration | releasing energy with use of oxygen |
| anaerobic respiration | obtaining energy from fuel molecules without use of oxygen |
| estuary | semi-enclosed coastal body of water composed of fresh and saline water |
| trophic levels | various levels in ecosystem—producers and successive steps removed from the producers |
| food chains | successive steps within an ecosystem illustrating the energy transfers between organisms as a result of consumption |
| food webs | interlocking change, woven into complex associations |
| detritus food webs | webs based on decomposing plant and animal material or animal waste products |
| pyramid of energy | shows production, use, and transfer of energy from one tropic level to another |
| 10% rule | on average, 10% of available energy is actually transferred at each step |
| pyramid of biomass | shows total amount of living material at each trophic level |
| pyramid of numbers | shows relative abundance of organisms at each trophic level |
| biogeochemical cycles | involve living organisms and geologic and chemical factors |
| Hydrologic cycle | all processes that account for the circulation of water through bodies of water, air, and land |
| gaseous cycle | circulation of a gas thru the environment, primarily in the atmosphere, as materials circulate from the air, thru the land and water, and back again |
| nitrogen fixation | process by which certain kinds of bacteria, either free-living in the soil or living in nodules (swellings) on plant roots, convert nitrogen to ammonia |
| sedimentary cycles | involve materials that move primarily from the land to the oceans and back to land again |
| ecosystem services | functions or processes of a natural ecosystem that provide benefits to human societies |