Biological Soil Crusts: Structure, Function, and Management

In arid and semiarid lands throughout the world, where the cover of vegetation is sparse or absent, the open spaces between the higher plants are generally not bare of autotrophic life, but covered by a community of highly specialized organisms. This soil-surface community consists of cyanob- teria, algae, lichens, mosses, microfungi, and other bacteria in differing proportions. Cyanobacterial and microfungal filaments, rhizinae and rhi- morphs of lichens, and the rhizinae and protonemata o...