consumes all fragments of dead matter, fungi and algae
The autotrophs in an ecosystem; green plants or chemosynthetic bacterium that converts light or chemical energy into organismal tissue
net primary production
equal to gross primary production minus the energy used by the primary producers for respiration
process by which a body of water becomes too rich in dissolved nutrients, leading to plant growth that depletes oxygen
process by which certain bacteria convert nitrogen gas to ammonia
increasing concentration of a harmful substance in organisms at higher trophic levels in a food chain or food web
first law of thermodynamics
energy is neither created nor destroyed or recycled, but may be converted from one form to another,
second law of thermodynamics
with each successive energy transfer or transformation in a system, less energy is available to do work, increases disorder (entropy)
fungi and prokaryotes that convert organic compounds to inorganic nutrients
gross primary production
rate at which solar energy is converted to the chemical energy of organic compounds
rate at which producers convert solar energy to the chemical energy of organic compounds, minus the energy used during respiration
how do iron levels affect phytoplankton populations
Iron stimulates the growth of cyanobacteria, which convert atmospheric N2 to nitrogenous minerals, stimulating the growth of phytoplankton
In the transition from each trophic level of the food chain to the next trophic level, there is about a(n)....
80% loss of energy
where does carbon come from?
how is carbon realesed back to the atmosphere by plants?
Cellular respiration releases carbon dioxide back to the atmosphere
Bacteria are especially important in making _____ available to plants
nitrogen.Carbon, in the form of CO2, is made available by several processes, including respiration and the burning of fossil fuels
The direct product of nitrogen fixation is _____
NH3. Ammonia is produced by nitrogen fixation. However, in the soil it is usually converted to ammonium (NH4+) before being taken up by plants
The phosphorus cycle lacks a(n) _____ component.