收稿日期: 2014-08-29
修回日期: 2014-09-12
网络出版日期: 2015-09-20
基金资助
国家自然科学基金项目(41101251,41301291,41330746);河北省自然科学基金项目(D2013302034,D2014205063)
Relation between Wind Erosion Amount and Wind Velocity in Farmland
Received date: 2014-08-29
Revised date: 2014-09-12
Online published: 2015-09-20
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。
王仁德 , 肖登攀 , 常春平 , 郭中领 . 农田风蚀量随风速的变化[J]. 中国沙漠, 2015 , 35(5) : 1120 -1127 . DOI: 10.7522/j.issn.1000-694X.2014.00134
The relation between soil loss by wind erosion and wind velocity in farmland was studied in the paper by long-term field observation and wind tunnel simulation. The results showed that the sand transport rate and wind erosion intensity both followed the exponential function with wind velocity increasing, which was the same with that getting in farmland and grassland by others using indoor wind tunnel simulation or situ testing of field wind tunnel, but it followed the power function in desert. Therefore, it was a common phenomenon that the soil loss by wind erosion followed the exponential function with wind velocity increasing in farmland and grassland and it followed the power function in desert. The difference in sand supply ability among different land types caused by the difference in erosion resisting factors of topsoil and surface roughness factors may be the main reason that led to the difference in changing laws of soil loss by wind erosion with wind velocity among the farmland, grassland and desert. It possibly reflected the case of sand supply limitation that the variation of wind erosion amount with wind velocity followed the exponential function in farmland and grassland, and it may reflect the case of sand supply unlimited that the variation of wind erosion amount with wind velocity followed the power function in desert.
Key words: wind erosion; wind velocity; sand supply limitation; exponential function
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