摘要
典型调查表明,在无定河流域绥德县80年—遇日降雨量120多mm条件下,林草措施具有显著的减蚀作用:农坡地一次降雨侵蚀模数达36660t/km^2,而一般草地侵蚀模数为5000～12000t/km^2,草地减少侵蚀70%～90%;坡度35°、被覆度70%的林地,加上工程整地措施,侵蚀模数为2000～5000t/km^2,减少侵蚀85%～95%;在相同自然条件下,林地减水效益为27.5%,减沙效益为47.7%,在有整地措施条件下,林地径流量较自然荒坡减少42.2%～77.1%.
Typical investigation showed that in Suide county of Wudinghe River basin, forest and grass measures have obvious effect on reducing soil erosion under the condition of more than 120 mm daily rainfall (eighty-year once). Once rainfall erosion modulus on slope farmland reached 36660 t/km^(2), while the value on usual grassland was 5000 ~ 12000 t/km^(2), erosion was reduced by 70% ~ 90%; erosion modulus on forest land, with slope of 35 degree and vegetation cover of 70%, also adopting engineering preparation of land, was 2000~ 5000 t/km^(2), erosion was reduced by 85% ~ 95% . In the same natural condition, runoff and sediment reduction benefit of forest land were 27.5% and 47.7% separately; in the condition with land preparation measures, run off amount of forest land redueed by 42.2% ~ 77. 1% comparing with natural slope land.
出处
《中国水土保持》
1997年第7期17-19,共3页
Soil and Water Conservation in China
关键词
无定河流域
林地
草地
减沙效益
Wudinghe River forest land grassland sediment reduction benefit
