| A | B |
|---|
| ecology | the study of the interactions of living organisms with one another and with their physical environment |
| habitat | the place where a particular population of a species lives |
| community | a habitat in which many different species live together |
| ecosystem | a community and all the physical aspects of its habitat |
| species diversity; diversity | the number of species living within an ecosystem |
| succession | regular progression of species replacement |
| primary succession | when succession occurs on land where nothing has grown before |
| seconday succession | when succession occurs in areas where there has been previous growth, such as in abandoned fields or forest clearings |
| primary productivity | the amount of organic material that the photosynthetic organisms of an ecosystem produce |
| producers | the organisms that first capture energy |
| consumers | the organisms which obtain energy to build their molecules by consuming plants or other organisms |
| trophic level | a group of organisms that have the same source of energy; a step in the food chain |
| herbivores | animals that eat plants or algae |
| carnivores | flesh-eating animals |
| omnivores | animals which eat both plants and animals |
| detritivores | organisms and animals which obtain their energy from the organic wastes and dead bodies that are produced at all trophic levels |
| decomposers | organisms which cause decay |
| food chain | a path of energy through the trophic levels of an ecosystem |
| food web | a complicated, interconnected path or energy |
| biomass | the dry weight of tissue and other organic matter |
| ground water | water retained beneath the surgace of the Earth |
| nitrogen fixation | the process of combining nitrogen gas with hydrogen to form ammonia |
