新疆策勒县新开垦农田地表蚀积变化

Changes of Wind Erosion and Wind Deposition on Surfaces of Newly Reclaimed Land in Cele County of Xinjiang Wei Autonomous Region

用插钎法结合气象数据对新疆维吾尔自治区策勒县开垦年限分别为2和1a农田地表进行风蚀风积观测,结果表明,沿主风向,防护林带前后0—3H(树高)内表现为风积,林前风积量明显大于林后风积量,防护林带之间中部主要以风蚀为主。红枣幼苗旁种植的冬小麦在一定程度上能有效地抵御红枣根部风蚀。未开垦的植被盖度3个不同的下垫面内,植被盖度和高度越大,其阻沙积沙能力越强。由于新开垦未种植裸荒地地表疏松无植被覆盖,表现出同阶段内最大的地表风蚀量。新开垦农田地表蚀积变化不仅与植被覆盖度、防护林结构、风速大小与风向紧密相关外,还与地表的微地形有关。

Pin-plugged method and meteorological observation method were adopted for analyzing wind ero- sion and wind deposition changes on surfaces of farmlands reclaimed in two years and in one year in Cele County of Xinjiang Wei Autonomous Region. The result indicates that wind deposition occurred in the range of 0--3 H （tree height） before and behind shelter belts along prevailing wind direction, the wind deposition volume upwind shelterbelt was more than that on the surface of downwind shelterbelt obviously, and on the surface of the middle part between two shelter belts it mainly showed wind erosion. Winter wheat planted in front of jujube tree seedlings could resist effectively wind erosion around jujube tree seedlings＇ roots in cer- tain degree. On the surfaces of three natural underlying surfaces preserved with different vegetation cover- age, the higher the vegetation coverage and plant height were, the stronger the resistance and wind deposi- tion ability were. Because it was loose and bare surface without cultivation and there was no vegetation~ on newly reclaimed land, maximum wind erosion amount occurred in every same phase. Wind erosion and wind deposition changes not only have close relationship with vegetation coverage, shelter belts＇ structure, wind velocity and wind direction, but also have relationship with surface microtopography.