| Dryland farming is one of the most important fields of agricultural research on which China has concentrated in recent years. Wind erosion is considered one of the more serious disasters in developing countries. The agro-pastoral ecotone in the north foot of Yinshan Mountain has been a main dust source of sandstorm in Northern China. It has been an urgent need to control and resist soil wind erosion as well as restoring ecological environment in this area. The study was carried out at Wuchuan County of the Inner Mongolia Autonomous Region, which lies in the North of China. Wuchuan County belongs to the semiarid to arid climatic zone. Wind erosion is determined by the interaction between erosive factors and factors of erodibility. Therefore, in studying patterns of soil erosion and in preventing and combating it, the relationship between the climatic conditions and factors of erodibility in their effects on wind erosion must be studied first. Subsequently one has to consider those factors that people can influence and utilize their mitigation to minimize the wind erosion. Some primary factors influencing soil wind erosion were qualitatively and quantitatively studied through meteorological data analysis, wild experiment and wind tunnel simulation test. This paper develops a simple index to show the importance of temporal variation in vegetation cover and to guide planting policies for wind erosion reduction. The main results of this thesis can be showed as blow: The region has potential wind erosion risk in the meteorological and soil factors. The main reason for serious wind erosion in this region is the nonidentity of the dynamic of wind erosion climatic factor, ratio of vegetation cover and soil water content in time. The differences of the various plant types covering a ground are very large in time. The time of crop and annual pasture covering ground are shortest and changed acutely with the time. Theirs monthly dynamic cover shows crop higher than manual pasture. While the shrub, perennial pasture and woodland in hill having covered the ground all the time, and theirs monthly dynamic cover behave shrub>perennial pasture>woodland in hill >crop>annual pasture. The respective amounts of monthly wind erosion for different plant types were also calculated. Amounts of wind erosion show annual pasture>crop>forest>perennial pasture> shrub. That is to say, shrub is the most effective in combating wind erosion, and crops without leaving stubble in winter and annual pasture are least effective. A simple index combining a wind erosive factor and a soil cohering factor allows quantification of expected erosion, a forecasting of the wind erosion hazard under the conditions of Wuchuan County, Inner Mongolia, that can be extended to other parts of the region. Because ground cover with much surface contact is absolutely necessary to reduce wind erosion, it is strongly recommended to plant perennial grasses with bush/shrubs above planting forests/woodland, annual pasture and crops that are totally harvested, in thatsequence. The results of wind tunnel simulation experiment show that wind erosion rate increased with the increasing of wind velocity. The wind speed of 18m/s is the turning point to aggravate the wind erosion. The higher of soil water content the wind erosion rate is the lighter. The' content of soil moisture equal 6% is turning point from severity to light for the rate of wind erosion. The effects of controlling and resisting wind erosion are different in different land utilizing types. The ability of controlling and resisting wind erosion shows shrub>natural grassland>farmland, and farmland protective plantation>woodland in hill. Returning farmland to shrub and perennial pasture also benefit to controlling and resisting wind erosion. Therefore it is should be given priority to return shrub and pasture in the region. Ecological theory is the first-line in restoring degraded ecosystem. It is different in different land utilizing typ...
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