| A | B |
|---|
| biomass | The dry weight of tissue and other organic matter used to determine the amount of energy present in trophic levels. |
| carnivore | Flesh-eating organism. |
| community | The many different species that live together in a habitat. |
| consumer | Organism that must obtain energy to build its molecules by consuming other organisms; heterotrophs. |
| decomposer | Organism that causes decay. |
| detritivore | Organism that obtains its energy by feeding on dead organisms or wastes. |
| diversity | The number of species living within an ecosystem. |
| ecology | The study of the interactions of living organisms with one another and with their environment. |
| ecosystem | Ecological system encompassing a community and all the physical aspects of its habitat. |
| food chain | Linear pathway of energy transfer in an ecosystem. |
| food web | A network of feeding relationships in an ecosystem. |
| ground water | Water found beneath Earth's surface. |
| habitat | Place where an organism lives. |
| herbivore | Organism that eats only plants or algae. |
| nitrogen fixation | Process of combining nitrogen gas with hydrogen to form ammonia. |
| omnivore | Animal that eats both plants and animals. |
| primary productivity | The amount of organic material that the photosynthetic organisms of an ecosystem produce. |
| primary succession | Succession that occurs in a newly formed habitat that has never before sustained life. |
| producer | Organism that makes its own food from energy and carbon atoms in its environment; autotroph. |
| secondary succession | An episode of succession that occurs in areas where there has been previous growth, such as abandoned fields or forest clearings. |
| species diversity | The number of species living within an ecosystem. |
| succession | The regular progression of species replacement that occurs after disturbance or the creation of new habitat. |
| trophic level | a group of organisms that have the same source of energy; a step in a food chain. |
