土壤湿度与风速对沙尘暴发生的贡献程度分析

在沙尘暴研究中，大风和下垫面的土壤湿度是影响沙尘暴发生的两个重要因子，它们分别以数值形式定量记录，但这种定量因子与沙尘暴发生的定性特征之间难以建立联系，从而影响了沙尘暴的定量研究。利用内蒙古中西部地区二连浩特、乌拉特中旗和乌海等3个观测站点2001年4月至2004年4月的土壤湿度、风速及相应的沙尘暴记录资料，采用数量化理论Ⅱ这种可以将定性分析与定量分析相结合的方法，研究了沙尘暴发生时风速和土壤湿度对沙尘暴的贡献程度。结果表明：在不同地区、不同地貌的自然条件下，风速和土壤湿度对沙尘暴发生的贡献程度相差甚远，乌拉特中旗和二连浩特地区风速的贡献大于土壤湿度的影响，而对乌海地区来说，土壤湿度对沙尘暴的贡献要大于风速的影响。

A contribution of soil moisture and wind speed to occurrence of dust storms

In the research of dust storm, the gale and soil moisture content of land surface are the two important fac- tors which affect the occurrence of dust storm, and they are recorded by quantitative form. It is hard to establish the relationship between the quantitative factors and the occurrence of dust storm. In this paper, the contribution degree of wind speed and soil moisture content to the occurrence of dust storm is analyzed by using Quantification Theory II which unifies the qualitative analysis and the quantitative analysis together, and using the data of soil moisture content and wind speed measured from April 2001 through April 2004 at the stations in Erleahot, Wulatezhongqi and Wuhai, which are located in Midwest of Inner Mongolia of China. The result shows that the contribution degree of wind speed and the soil moisture content has obvious discrepancy in different regions which have different geomorphy and natural conditions. In Wulatezhongqi and Erleahot regions, the contribution of wind speed is bigger than that of the soil moisture content to the occurrence of dust storm, however, the contribution of soil moisture content to the occurrence of dust storm is bigger than that of wind speed in Wuhai.