Rangeland soil quality--Soil biota (Soil Quality Information Sheet, Rangeland Sheet 8)

TitleRangeland soil quality--Soil biota (Soil Quality Information Sheet, Rangeland Sheet 8)
Publication TypeGovernment Report
Year of Publication2001
AuthorsTugel A.J., Herrick JE, Shaver P.L., Pellant M.
PublisherUSDA, Natural Resources Conservation Service
ARIS Log Number142823
Keywordsgovernment publication
AbstractSoil biota include an incredible diversity of organisms. Soil biota are concentrated in plant litter, the upper few inches of soil, and along roots. Soil organisms interact with one another, with plant roots, and with their environment, forming the soil food web. Through their interactions in the soil food web, the activities of soil biota link soil with the plants and animals above ground. Soil organisms perform essential functions that allow soil to resist degradation and provide benefits to all living things. Soil biota multiply rapidly when organic material, roots, and plant litter, their food source, are available and the soil is moist and warm. Proper management of the plant community is the best strategy for maintaining the benefits of the soil food web. Plant production and the supply of organic matter can be maintained or enhanced by timely grazing, the proper frequency of grazing, and control of the amount of vegetation removed. If the plant community is overgrazed, a reduction in the amount of surface plant material and roots will result in less food for soil organisms. As biological activity decreases, a downward spiral of the important functions of soil organisms results in a lower content of organic matter and impedes nutrient cycling, water infiltration, and water storage. Heavy grazing also can reduce the abundance of nitrogen-fixing plants, causing a decrease in the supply of nitrogen for the entire plant community. Pesticides that kill above-ground insects can also kill beneficial soil insects. Herbicides and foliar insecticides applied at recommended rates have a smaller impact on soil organisms. Fungicides and fumigants have a much greater impact on the soil organisms.
Government BodySoil Quality Institute, Grazing Lands Technology Institute, and National Soil Survey Center, Natural Resources Conservation Service, USDA; the Jornada Experimental Range, Agricultural Research Service, USDA; and Bureau of Land Management, USDI