论文部分内容阅读
从流域产流规律及水土保持措施改变引起的土壤水分状况和流域蒸散发的变化等方面评价了黄土丘陵沟壑区泉家沟流域水土保持措施变化对流域水分生态环境的影响。结果表明:水土保持与生态建设过程改变了土地利用结构,对小流域水环境变迁具有很大的影响作用,主要表现在:减少地表径流量,径流模数1996～2000年平均较1980～1985年减少了36.1%;不同治理措施土壤水分状况不同,灌木林地、人工草地和乔木林地均存在深度和厚度不等的土壤“干层”;不同地貌部位土壤储水差异很大,阴坡的水分环境优于阳坡,沟底优于峁顶,缓坡优于陡坡;林草措施对流域总蒸散量起着决定性作用,1991～1995年流域林草地面积达到最大,总蒸散量也达到最大,与治理初期相比,总蒸散量累计增加了56.3mm。
The effects of changes in soil and water conservation measures on the water eco-environment of the watershed in Quanjiagou watershed in the gully region of the Loess Plateau were evaluated based on the regularity of runoff in the watershed and the changes of soil moisture caused by changes in soil and water conservation measures. The results showed that the process of soil and water conservation and ecological construction changed the land use structure and had a great effect on the water environment change in the small watershed. The main features were as follows: reducing the surface runoff, the average runoff modulus from 1996 to 2000 was more than that from 1980 to 1985 With a decrease of 36.1%. Soil moisture status under different control measures was different. There was soil “dry layer ” with different depths and thicknesses in shrub land, artificial grassland and arbor forestland. Soil water storage varied greatly in different landforms. The water environment is superior to the sunny slope, the ditch bottom is better than the top, and the gentle slope is better than the steep slope. The forest and grass measures play a decisive role in the total evapotranspiration of the basin. From 1991 to 1995, the area of forest and grassland reaches the maximum and the total evapotranspiration reaches the maximum, Compared with the initial stage of treatment, total evapotranspiration has increased by 56.3mm.