{"thcode":2,"term":{"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."},"uf":[{"name":"biocrusts","usewith":false},{"name":"cryptobiotic soil crusts","usewith":false},{"name":"cryptogamic soil crusts","usewith":false},{"name":"microbiotic soil crusts","usewith":false}],"bt":[{"code":1080,"name":"soil resources","parent":777,"scope":"Natural resources of unconsolidated fragmented rock, humus, and mineral matter that cover the surface of the earth."},{"code":777,"name":"natural resources","parent":1174,"scope":"Stocks of anything naturally occurring that have a beneficial use for man including economic, nutritional, recreational, aesthetic, and other benefits."},{"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":187,"name":"community ecology","parent":921,"scope":"Study of the relationships of species that interact in a common area."},{"code":2044,"name":"soil horizons","parent":1199,"scope":"Layers in soil defined by physical, chemical, biological, or mineralogical properties which vary with depth."}]}