中文摘要：

土壤抗风蚀性能主要取决于土壤颗粒质量及土壤质地等因素。土壤风蚀特征是建立土壤风蚀模型及土壤保持的基础。本研究选择了干旱的阴山北麓农牧交错带裸露耕地的表土颗粒为研究对象，对该区域的抗风蚀因素进行了试验研究和分析，并结合研究区域地表土壤性质，提出了定量反映风蚀过程中表土物质的损失程度的物理量一一增失比例系数（WEVI），即WEVI=粗化颗粒含量／易蚀颗粒含量。结果表明：2004～2007年，增失比例系数从2．10增加到3．46，定量地反映出了2004~2007年的土壤颗粒粗化和细颗粒的流失程度，进而说明了裸露耕地的退化程度。

英文摘要：

Soil resistance characteristics depend on the soil particle mass, composition etc. The properties of the soils, which are in- fluenced by wind erosion, are very important information for the wind erosion prediction and conservation. Soil wind erosion in bare till- age in agro - pastoral ecotone of northern foot of Yiushan is developing rapidly and receiving widespread attention. The study focused on the experiment of the resistance characteristics of aeolian soil factors to wind erosion. The characteristic parameter was found which can well describe the local topsoil particle loss. It was named as Wind Erosion Variation Index（WEVI）, which is the ratio of coarse mass and fine mass. The experimental results showed the WEVI changed from 2.10 in 2004 to 3.64 in 2007 which gave the quantitative in- formation about the particle in topsoil coarsen and the fine particle less. Therefore, the local bare tillage is subjecting to degradation.