{"thcode":2,"term":{"code":187,"name":"community ecology","parent":921,"scope":"Study of the relationships of species that interact in a common area."},"uf":[],"bt":[{"code":921,"name":"population and community ecology","parent":1174,"scope":"Interactions of a single species (population) or an association of different species (community) occupying a particular region, including their biotic and abiotic environments."},{"code":1174,"name":"topics","parent":1,"scope":"Themes, subjects, and concerns for which USGS information resources are relevant."},{"code":1,"name":"Categories","parent":null,"scope":"Thematic terms for categorizing information resources.  This thesaurus is intended to support finding and understanding scientific information."}],"nt":[],"rt":[{"code":2268,"name":"biological soil crusts","parent":1080,"scope":"Communities commonly found on the soil surface in arid and semi-arid ecosystems, these consist of mosses, cyanobacteria, lichens, algae, and microfungi, which weave together and adhere to the soil to form a matrix that lessens erosion, supports nitrogen fixation, and retains moisture. These organisms are important to the functioning of ecosystems and to the organization of plant and soil communities."},{"code":308,"name":"ecological competition","parent":310,"scope":"The struggle between members of two or more species for scarce environmental resources."},{"code":311,"name":"ecology","parent":650,"scope":"Study of the relations between living plants and animals and their environment."}]}