| A | B |
|---|
| renewable resources | Resources naturally replaced in a relatively short period of time |
| nonrenewable resources | Natural resources that are not replaced as the are used |
| pollution | Any change to the environment that has a negative effect on living things |
| Clear-cutting | Process of cutting down all trees in an area at once |
| selective cutting | Cutting down only some trees in a forest and leaving a mix of species behind |
| sustainable yield | Regular amount of a renewable resource such as trees that can be harvested without reducing future supply |
| fishery | An area with a large population of valuable ocean organisms |
| aquaculture | Practice of raising fish and other water-dwelling organisms for food |
| biodiversity | Number of different species in an area |
| keystone species | Species that influences the survival of many other species in an ecosystem |
| extinction | Disappearance of all members of a species |
| endangered species | Species in danger of becoming extinct in the near future |
| threatened | Species that could become endangered in the near future |
| habitat fragmentation | Breaking larger habitats into smaller isolated pieces or fragments |
| poaching | Illegal killing or removal of wildlife species |
| Captive breeding | Mating of animals in zoos or wildlife preserves |
| John Muir | Started the Sierra Club |
| Theodore Roosevelt | Established first wildlife refuge in Florida |
| Wangari Maathai | Founded the Green Belt movement |
| Gifford Pinchot | First director of US Forest service |
