宁夏河东沙地不同植被覆盖度的土壤起沙特征试验研究

为了评价宁夏河东沙地不同生态破坏与植被恢复措施的防沙治沙效果,利用自行设计的5个高度降尘接沙仪和4台内蒙古农牧大学生产的水平输沙接沙仪,通过人工吹风的方式,于2004年5月20—23日在不同植被覆盖度的下垫面上,开展不同垂直高度和不同距离的降尘试验和不同垂直高度的沙尘粒子截留试验。植被类型为自然裸露沙丘、低覆盖度天然草场、围栏禁牧的自然恢复草场、人工草方格沙丘治理结合飞播的生态恢复治理草地及原退耕还牧的复垦农田。结果表明,裸露沙丘土壤风蚀最严重,防沙治沙以围栏禁牧效果最好,其次为草网格治理,复垦农田和流动沙丘均容易起沙。

Experimental Research on Sand Blown Characters from Sandy Land with Different Vegetation Cover in East of Yellow River in Ningxia

In order to evaluate the effect of vegetation recovering measurements for the east sandy land of Yellow River in Ningxia, we conducted experiment on dustfall at different height and different distance from tuyere, and on sand trap at different height in May 20-23, 2004. The applied instruments are the Horizontal Dustfall Acceptor at five heights designed by ourselves and the Vertical Sand Interceptor produced by the Agriculture and Stockbreeding College of Inner Mongolia. The underlying surfaces for experiment include bared sand dune, low-covered natural grassland, closed rehabilitating grassland, ecological controlled grass- land compounding with straw-checkerboard and air seeding measurements, and recultivated farmland. Results show that the most serious wind erosion occurred on bared sand dune, the best sand controlling effect on the enclosed grasslands and the second effect on straw-checkerboard areas; the recovered farmland and the moving dunes are ready for wind erosion.