Aerodynamics contribution for monitoring multilayer rough surfaces

摘要

The phenomenon of desertification is one of the major environmental problems. The causes of desertification are numerous, complex and diverse origins. However, with a human time scale, aspects related to poverty, population pressure, new crop techniques introduced, including the management of natural resources, seem to dominate in most cases. Wind erosion is considered as the most distinguishable symptoms of desertification. It is both its product and its main ally. Wind erosion occurs mainly in areas where the wind is sufficiently strong and the soil is bare, dry and crumbled. It is in hyper-arid, arid and semi-arid that the wind erosion is most active. Wind erosion is a natural phenomenon originally due to the combined effect of climate and the state of the soil surface. The introduction of some inappropriate technologies for working the soil in areas which are threatened by wind erosion, has deteriorate the situation further by promoting the growth of cultivated areas and therefore the establishment of bare soil, often quite crumbled so easily submitted to wind stripping. The overall objective of this work is to study the particular impact of wind erosion on the soil surfaces shape, and the study will interest smooth and flat surfaces.