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三峡库区现有坡地植被是由亚热带常绿阔叶林演替而来的天然次生林和荒地草坡及人工林植被。森林覆盖率从20世纪40年代的45.5%降至1985年的21.7%,而且面积分布不均匀呈“岛状”和“斑块状”。坡地植被的退化导致了土壤瘠薄。土壤石砾含量6%~30%;土层较薄40~60cm;土壤母质松软再加之人们不合理利用土地,使水土流失加剧。为了控制库区坡地植被─土壤环境变化,防止进一步土壤侵蚀,1992年采用生物活篱笆复合农林经营技术。生物活篱笆是采用速生、萌生力强、能固N的植物材料沿等高线种植,使较陡坡地保持水土达到合理利用土地的目的。试验选择刺槐、黄荆、马桑、新银合欢、紫穗槐、龙须草、香根草等乔灌草。种植3a后植被覆盖达35%,产沙量3.3g/m2,而人为翻耕没有植被覆盖的产沙量高达37.97g/m2。
The existing slope vegetation in the Three Gorges Reservoir Area is a natural secondary forest and a fallow grassland and plantation forest which are derived from subtropical evergreen broad-leaved forest. Forest cover decreased from 45.5% in the 1940s to 21.7% in 1985, and unevenly distributed “islands” and “plaques”. Degradation of sloping vegetation led to soil infertility. Soil gravel content of 6% to 30%; soil thinner 40 ~ 60cm; soil soft parent material coupled with unreasonable people use the land, soil erosion worse. In order to control the slope vegetation in the reservoir area ─ ─ soil environment changes, to prevent further soil erosion, in 1992 the use of biological living Fence agroforestry management techniques. Biological live fence is the use of fast-growing, strong sprout, capable of N plant material along the contour planting, so steep slope to maintain soil and water to achieve the purpose of rational use of land. Robinia pseudoacacia, Huang Jing, Masson, New Acacia, Amorpha fruticosus, asparagus, vetiver and other trees and shrubs. After planting 3a vegetation cover up to 35%, sediment yield 3.3g / m2, and artificial tillage without vegetation cover up to 37.97g / m2 of sediment yield.