Impact of Wind Erosion On Soils In Arid and Semi-Arid Landscapes.

Wind erosion is a significant aeolian process that appreciably affects soils and landscapes in dryland systems, comprising almost forty percent of the Earth’s land surface.  This presentation will highlight the important contribution of wind-induced sediment redistribution to soil genesis. Wind erosion often occurs when coarse-textured soils are bare, loose, dry and subjected to erosive winds.  Although wind erosion occurs in almost all climatic regions, it is a dominant process in arid and semi-arid regions.  Soil characteristics have a great impact on wind erodibility of soils.   For example, fine and very fine sandy soils produce little aggregation and are much more wind-erodible than soils with more clay that readily form non-erodible aggregates.  The effects of wind erosion occur at the field, landscape, region, and global scales.   Loss of nutrients and water holding capacity affects crop productivity at the field scale.  At the landscape and regional scales, soil redistribution causes geomorphic modification of the landscape to produce features such as dunes of various descriptions and in some cases regional modifications of the surface texture.  Changes in loess depth and surface texture particle size with proximity to the sediment source have been widely reported.   In addition, wind erosion at the landscape and regional scale causes changes in biogeochemical cycles affecting the composition, productivity and spatial patterns of vegetation that subsequently affects soil properties.  Dust entrainment and transport at the regional scale may produce atmospheric dust that impacts soils globally.