| A | B |
|---|
| greenhouse effect | the natural situation in which heat is retained by this layer of greenhouse gases |
| polar zones | cold areas where the sun's rays strike Earth at a very low angle. |
| temperate zones | Between polar and tropics, ranges between hot and cold |
| tropical zone | near the equator, nearly always warm |
| biotic factors | the biological influeneces on organisms within an ecosystem |
| abiotic factors | physical, or nonliving, factors that shape ecosystems |
| habitat | the area where an organism lives |
| niche | the full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions |
| competitve exclusion principle | states that no two species can occupy the same niche in the same habitat at the same time |
| predation | an interaction in which one organism captures and feeds on another organism |
| symbiosis | any relationship in which two species live closely together |
| mutualism | both species benefit from the relationship |
| commensalism | one member of the association benefits and the other is neither helped nor harmed |
| parasitism | one organism lives on or inside another organism and harms it |
| ecological succession | this series of predictable changes that occurs in a community over time |
| primary succession | sucession that occurs on surfaces where no soil exists |
| pioneer species | the first species to populate the area |
| secondary succession | succession following a disturbance that destroys a community without destroying the soil |
| biome | a complex of terrestrial communities that covers a large area and is characterized by certain soil and climate |
| microclimate | the climate in a small area that differs from the climate around it |
| decidous | a tree that sheds its leaves during a particular season each year |
| humus | a material formed from decaying leaves and other organic matter that makes soil fertile |
| taiga | dense evergreen forests of coniferous trees |
| permafrost | a layer of permanently frozen subsoil |
| plankton | tiny, free floating organisms that live in both freshwater and saltwater environments |
| phytoplankton | unicellular algae |
| zooplankton | planktonic animals |
| wetland | an ecosystem in which water either covers the soil or is present at or near the surface of the soil for at least part of the year |
| estuaries | wetlands formed where rivers meet the sea |
| detritus | made up of tiny pieces of organic material that provide food for organisms at the base of the estuary's food web. |
| mangrove swamps | coastal wetlands that are widespread across tropical regions, including southern Florida and Hawaii |
| photic zone | well lit upper layer of the oceans |
| aphotic zone | permanently dark layer of the oceans below the photic zone |
| coastal ocean | extends from low tide mark to the outer edge of the continental shelf, the relatively shallow border that surround the continents |
| coral reefs | diverse and productive environment named for the coral animals that make up its primary structure |
| benthos | organisms that live attached to or near the bottom |
| agriculture | the practice of farming |
| monoculture | large fields are planted with a single variety year after year |
| soil erosion | the wearing away of surface soil by water and wind |
| desertification | turning areas into deserts |
| deforestation | loss of forests |
| aquaculture | the raising of aquatic animals for human consumption |
| biodiversity | the sum total of the genetically based variety of all organisms in the biosphere |
| ecosystem diversity | the variety of habitats, communities, and ecological processes in the living world |
| genetic diversity | the sum total of all the different forms of genetic information carried by all organisms living on Earth today |
| extinction | occurs when a species disappears from all or part of its range |
| habitat fragmentation | development often splits ecosystems into pieces |
| biological magnification | concentrations of a harmful substance increase in organisms at higher trophic levels in a food chain or food web |
| invasive species | plants and animals that have migrated to places where they are not native |
| conservation | the wise management of natural resources |
| ozone layer | the atmosphere contains a relatively high concentration of ozone gas |
| global warming | the increase in the average temperature of the biosphere |
