Abiotic controls on the functional structure of soil food webs

TitleAbiotic controls on the functional structure of soil food webs
Publication TypeJournal Article
Year of Publication1989
AuthorsWhitford WG
JournalBiology and Fertility of Soils
Date Published1989
Accession NumberJRN00089
Call Number00388
Keywordsabiotic,food webs, anhydrobiosis, article, articles, bacteria,food web, cryptobiosis, food web, abiotic controls, fungi,food web, journal, journals, mite,food web, nematode,food web, protozoa,food web, soil, food web

The hypothesis that the trophic structure of soil food webs changes as a result of the abiotic environment was examined by reviewing studies of soil biota. In dry soils with a water potential below -1.5 MPa, most bacteria, protozoans, and many species of nematodes are not active. These taxa persist in the soil in a state of anhydrobiosis. Because soil fungi grow at soil water potentials of -6.0 to -8.0 MPa, soil food webs in dry environments appear to be fungal-based and fungal grazers in dry environments appear to be predominantly fungiphagous mites. There is indirect evidence that some species of fungiphagous mites remain inactive in dry soils in a state of "crytobiosis". In habitats where there is insufficient vegetative cover to shade and modify the soil surface, the functional soil food web consists of fungi and a few taxa of soil acari for extended periods of time.