click below
click below
Normal Size Small Size show me how
18.4 terms
| Term | Definition |
|---|---|
| ammonification | the formation of ammonia compounds in the soil by the action of bacteria on decaying matter |
| biogeochemical cycle | the circulation of substances through living organisms from or to the environment |
| carbon cycle | the movement of carbon from the nonliving environment into living things and back |
| denitrification | the liberation of nitrogen from nitrogen-containing compounds by bacteria in the soil |
| groundwater | the water that is beneath the earth's surface |
| nitrogen cycle | the process in which nitrogen circulates among the air, soil, water, plants, and animals in an ecosystem |
| nitrogen fixation | the process by which gaseous nitrogen is converted into nitrates, compounds that organisms can use to make amino acids and other nitrogen containing organic molecules |
| nitrogen-fixing bacteria | a bacterium that converts atmospheric nitrogen into ammonia |
| phosphorus cycle | the cyclic movement of phosphorus in different chemical forms from the environment to organisms and then back to the environment |
| transpiration | the process by which plants release water vapor through stomata; also the release of water vapor into the air by other organisms |
| nitrification | nitrites and nitrates are produced by bacteria in soil |
| water cycle | the continuous movement of water between the atmosphere, the land, and the oceans |