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为了解阴山北麓农牧交错带的土壤风蚀特性,采用SCC-6型集沙仪在野外自然风况下对风蚀物进行实地收集试验并对其粒度组成进行分析研究,得到了阴山北麓农牧交错带裸露耕地土壤在自然风况下风蚀物沿高度的变化规律,揭示了风蚀物沿高度的变化规律和不同跃移颗粒体的粒度组成沿高度的变化特征。并利用室内风洞研究了不同风速作用下,不同风力作用时间内,风蚀物含量沿高度的变化规律和风蚀量与风速的关系。结果表明:阴山北麓农牧交错带土壤风蚀是一种近地表的风沙运动,风蚀物跃移颗粒体主要集中在7.5～43.5cm高度,风蚀物含量沿高度呈一递减函数,对幂函数、指数函数和对数函数均具有较好的相关性;风蚀物颗粒组成与风蚀强度和地表状况关系密切;风蚀物颗粒组成以某一粒径范围、某一高度为界随高度的变化而表现出明显的规律性;风蚀量沿高度的变化与风力作用时间有关,风蚀量随风速的增大呈指数增加。为研究该区域土壤风蚀规律及提出合理防风固沙措施奠定了基础。
In order to understand the characteristics of soil erosion in the ecotone between agriculture and animal husbandry in the northern part of Yinshan Mountain, SCC-6 sand-collecting instrument was used to collect and analyze the wind erosion materials under the natural wind conditions in the wild and the particle size distribution was analyzed. The change rule along the height of wind eroded material in the uncultivated land in the pastoral zone shows the variation along the height of the wind eroded material and the variation of particle size distribution along the height of different leached particles. The indoor wind tunnel was used to study the variation of wind erosion contents along the height and the relationship between the amount of wind erosion and wind speed under different wind speeds and wind forces. The results show that the wind erosion is a near-surface wind-blown movement in the ecotone between agriculture and animal husbandry in the northern part of Yinshan Mountain. The levitation particles are mainly concentrated in the height of 7.5 ~ 43.5 cm. The content of wind erosion substance presents a decreasing function along the height, Exponential function and logarithmic function have a good correlation; the composition of the erosive particles is closely related to the wind erosion intensity and the surface conditions; the composition of the erosive particles shows a certain particle size range and a certain height as the boundary changes with the height Obvious regularity; the change of wind erosion along the height is related to the time of wind action, and the amount of wind erosion increases exponentially with the increase of wind speed. This study lays the foundation for studying the law of soil erosion in the region and putting forward the measures of windbreak and sand fixation.