不同高度阻沙栅栏蚀积过程及防沙效益研究

通过对不同高度阻沙栅栏蚀积过程的野外观测,结合同时期区域风况资料,分析了阻沙栅栏前后地表蚀积形态、蚀积量以及蚀积强度的时空变化特征。结果表明,在沙源充足条件下,不同高度阻沙栅栏上风向表现为风沙堆积,下风向风蚀与堆积共存,且程度与栅栏高度有关,栅栏总体蚀积量和蚀积强度的变化趋势与下风向变化趋势相近。其中,60和70cm高度阻沙栅栏风沙堆积量最大,防沙效果最佳,但二者积沙方向存在差别。70cm高度阻沙栅栏上风向积沙较多;60cm高度阻沙栅栏下风向积沙较多。在实际应用中,应依据防护对象合理配置阻沙栅栏并适时加高,避免阻沙栅栏过低或过高,进而影响防沙效果。此外,依据断面形态、蚀积量和蚀积强度的变化,将栅栏前后分为风沙堆积区、风蚀区和蚀积平衡区。

Process of Aeolian Sand Erosion and Deposition and Sand Controlling Effect of Fences with Different Height

A case study on the quantity of aeolian sand erosion and deposition of fences with different height was carried out in the observation station of Chinese Academy of Sciences at southeast of Tengger Desert.The fences with different heights were deployed in the field.Combining the observed weather data and the data of aeolian sand erosion and deposition of barrier-free flat desert over the same period,it is concluded that the sand prevention effect of the fences with the height between 50 and 90 cm is better ...