| A | B |
|---|
| ecology | the study of the interactions of living organisms with one another and their physical environment |
| habitat | the place where a particular population of a species lives |
| community | the many different species that live together in a habitat |
| ecosystem | a community and all the physical aspects of its habitat |
| species diversity or diversity | the number of species living within an ecosystem |
| seccession | the regular progression of species replacement |
| primary seccession | when seccession occurs on land where nothing has grown before |
| secondary seccession | when seccession occurs where there has been previous growth |
| primary productivity | the amount of organic material that photosynthetic organisms of an ecosystem produce |
| producers | the organisms that first capture energy |
| consumers | all the organisms in an ecosystem except those that first capture energy |
| trophic level | levels that create food webs and chains that are determined by the organism's source of energy |
| herbivores | animals that eat only plants |
| carnivores | animals that eat only meat |
| omnivores | animals that eat meat and plants |
| tertiary consumers | carnivores that consume other carnivores |
| detritivores | organisms that obtain their energy from the organic wastes and dead bodies that are produced at all trophic levels |
| decomposers | organisms that decay other organisms |
| food chain | the path of energy through the trophic levels of an ecosystem |
| food web | a complicated, interconnected path of energy |
| biomass | the dry weight of tissue and other organic matter |
| ground water | the water retained beneath the surface of the earth |
| nitrogen fixation | the process of combining nitrogen gas with hydrogen to form ammonia |
