The Impact of Vehicles on Desert Soil Stabilizers

Abstract

Because of climatic conditions, deserts have an apparently sparse plant cover. Shrub communities of deserts in the western United States change progressively in composition, density, and size of individuals with increasing height above valley floors, reflecting progressive changes in temperature and abundance, depth, and composition of water (Hunt and Durrell, 1966). The soil between shrubs may appear bare, but it is commonly occupied by microfloral crusts and at least seasonally supports annual plants, whose root systems continue to have a stabilizing effect even if the plant has died. In fact, the sparsity of shrubs creates soil-moisture conditions favorable to microflora (Friedmann and Galun, 1974). Extensive areas of soil not protected by vegetation are covered by rock pavements, commonly of great antiquity. Even here a floral niche is found by diaphanous algae. Even bare soil is protected by silt-clay (mechanical) or salt crusts. The views and conclusions contained in this chapter are based on the author’s studies or experiences and do not necessarily reflect the official viewpoint or policy of any U.S. government agency.