Because of irrational structure and low benefits of windbreaks in northern Shanxi,the wind erosion quantity of the soil in severe section can reach as high as 120~135 m3/hm2.In order to provide a theoretical basis for design of windbreaks,based on an analysis of occurring rules of hazardous wind,characteristics of sandstorms and mechanical structure of topsoil in northern Shanxi,a research on key factors for design of windbreaks had been done by establishing mathematical models.The results are as following:...