不同组合间距的尼龙阻沙网积沙形态特征对比  

Morphological features of sand deposition caught by nylon net windbreak combinations with different intervals

作　　者：康向光[1] 李生宇[1] 王海峰[1] 马学喜 雷加强[1] 

机构地区：[1]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011 [2]中国科学院大学,北京100049

出　　处：《干旱区地理》2015年第2期283-291,共9页Arid Land Geography

基　　金：新疆维吾尔自治区科技支疆项目(201291106)资助

摘　　要：在塔克拉玛干沙漠腹地垄间平沙地,布设了两条尼龙阻沙网水平组合防沙实验,组合间距分别为2H、5H、10H、15H(H为阻沙网高度),一个风季中对实验设置的地形及纵断面蚀积量进行了动态观测。结果表明:(1)各尼龙阻沙网组合形成有规律的地表蚀积空间分布格局:形成以阻沙网为核心的积沙区,其上下风侧分布有较稳定的风蚀区,两条阻沙网之间存在临时的风蚀区。(2)在阻沙网前后形成与阻沙网高度相近的积沙体,在第一条阻沙网上风侧区域,积沙厚度与水平距离呈指数函数关系,在阻沙网背风侧,积沙厚度与水平距离呈二次函数关系。(3)2H和5H积沙体纵断面呈单峰状,风季中后期形似"几"字形,而10H和15H呈双峰状,风季中后期形似"M"字形。(4)阻沙网组合间距越小,积沙分布就越集中,形体越高大,反之则越分散,风季末阻沙网积沙体地形起伏度、平均坡降、积沙体积比、积沙断面面积轮廓比大小排序均为2H>5H>10H>15H。(5)阻沙网积沙体积具有随阻沙网间距增大而降低的趋势,观测断面最大积沙体积5HH>2H>15H>10H,5H、2H、15H分别较10H大13.20%、12.34%、3.78%,可见,5H防沙效果最优。As one of the most effective sand-controlling measures, nylon net windbreak has an excellent sand-blocking capability, has been applied to lots of transportation projects in desert areas of China. In a practical application, especially in drifting desert, two or more pieces of nylon net windbreaks were always settled togeth- er, however, few studies on its best combinatorial space between two pieces of windbreaks has rarely been report- ed so far. The paper conducted a sand-controlling experiment of two nylon-net-windbreaks combination with dif- ferent space length treatments, which were 2 times （2H）, 5 times （5H）, 10 times （10H）, and 15 times （15H） as broad as windbreak＇ s height on an inter-dune corridor in the hinterland of the Taklimakan Desert, Xinjiang, China. The landforms and erosion-deposition around all nylon-net windbreak combinations were investigated dynamical- ly in a wind season. The results indicate that the intensities of erosion-deposition around the windbreak combina- tions were distributed in a clear spatial pattern including one sand-depositing region around windbreaks, two de- flation regions in its windward and leeward neighborhoods, and one temporary deflation region between the two windbreaks. A sand ridge with similar height like windbreak was formed in the sand-depositing region; in the windward part of the first windbreak, the thickness of sand deposition increased exponentially with the horizontal distance to windbreak shortening; in the leeward part of the windbreaks, the thickness of sand deposition de- creased with the horizontal distance to windbreak increasing, whose relation can be formulated as a standard qua- dratic function. The profiles of sand deposition cross section of 2H and 5H showed as single apex with a shape of Chinese character of＇ 几＇ in the middle and later period of wind season; But the profiles of sand deposition cross section of 1 OH and 15H showed as double peaks with a shape of English character of ＇M＇ in the middle and later period

关 键 词：蚀积强度 积沙形态 组合间距 尼龙阻沙网 

分 类 号：S288[农业科学—农业水土工程] X171[农业科学—农业工程]