Hydroclimatology of wind erosion in arid and semiarid envirmonments

Abstract

The wind has been active as an erosive agent throughout geological times in many parts of the world. It takes up soil from one place and deposits it in another. Outstanding examples are the extensive loess deposits along the Huanghe River (Yellow River) in China, and along the Missouri and Mississippi rivers in the USA. However, in recent years, wind erosion has become more active and more destructive on a global scale, due to the action of man, which is associated with a drastic growth of the world's population over the past century. This accelerated erosion has been caused by inadequate land management including, clearance of the natural vegetation, overgrazing and non-adapted agricultural practices leading to land degradation. In the 1930, a decreased precipitation coupled with intensive agricultural activities caused a dramatic increase in wind erosion in the Great Plains of the United States, resulting in the so-called Dust Bowl. Another example is the Mu Us region in North China with an annual precipitation of 400 mm, which was once grassland partially covered with forest, while now is one of the major sources of dust in the world as a result of overgrazing and agricultural practices.