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采用长期野外观测和风洞模拟实验相结合的手段就农田风蚀量随风速的变化问题进行研究。结果表明:无论是野外观测的农田输沙强度,还是风洞模拟得到的风蚀强度随风速变化趋势均符合指数函数。这与前人通过实验得到的其他地区农田和草地风蚀量随风速变化的趋势一致,说明农田和草地上风蚀量随风速增加呈指数规律变化是一种普遍存在的现象。表土抗蚀性因子和地表粗糙因子不同导致的沙源供应能力的差异,可能是不同地类之间风蚀量随风速变化规律不同的主要原因。农田和草地沙源供应有限,风蚀量随风速增大呈指数规律变化;沙漠地区沙源充足,风蚀量随风速增加呈幂函数变化。本研究对于确定沙源供应条件对于风蚀量与风速关系的影响,构建基于有限沙源供应的风蚀模型具有重要意义。
Using the combination of long-term field observation and wind tunnel simulation experiments, the wind erosion of farmland with wind speed was studied. The results show that both the strength of sand transport and the intensity of wind erosion simulated by wind tunnel are consistent with the exponential function. This is consistent with the tendency of the amount of wind erosion in farmland and grassland varying with the wind speed in other areas obtained through previous experiments, which shows that it is a common phenomenon that the amount of wind erosion on farmland and grassland changes exponentially with the increase of wind speed. The difference of sand supply capacity caused by the difference of topsoil corrosion resistance and surface roughness may be the main reason that wind erosion varies with wind speed in different types of land. There is a limited supply of sand sources in farmland and grassland, and the amount of wind erosion changes exponentially with the increase of wind speed. There is ample sand source in the desert area and the amount of wind erosion changes exponentially with the increase of wind speed. This study is of great significance to determine the impact of sand supply conditions on the relationship between wind erosion and wind speed, and to build a wind erosion model based on the limited supply of sand.