姚安县典型小流域水土保持生态修复监测与评价

对长江上游云南紫色土区小流域水土流失造成的退化生态系统的人为诱导修复进行了监测与评价．结果显示，有自然恢复条件的小流域退化生态系统，经过4年人为参与的不同措施修复，流域生态系统类型、结构和功能都得到一定程度改善．生态系统类型增加，较稳定和趋于正向进展演替的生态系统类型的水平分布面积扩大，人为重点修复生态系统类型的立体垂直结构逐渐显现，生物多样性和生物量增加，土壤理化特性得到改良，土壤侵蚀减弱，森林覆被率提高，修复效果明显．干扰荒草地、人工林、自然恢复和坡改梯措施的土壤流失量3年内分别减少46．9％-50．1％，49.6％-59．3％，29．5％-66．4％和65．1％-76．1％．

Monitoring and Evaluation on Ecological Restoration for Water and Soil Conservation of Typical Small Watershed in Yao'an County

The man-induced ecological restoration of degraded ecosystem caused by water erosion within typical small watersheds on purple soil area in the upper reaches of the Yangtze River in Yao'an County, Yunnan Province has been monitored and evaluated. It was showed by the results that the structure and function of the degraded ecosystem with natural recovery potential has been improved after 4-year-long period of man-induced ecological restoration. Both the ecosystem types and the area covered by more stable and positively successive ecosystem types apparently increased. The vertical structure of the ecosystem types restored with artificial measures was appearing, the biodiversity and biomass were promoted, the physical and chemical properties of local soil were improved along with the reduction of water erosion and increment of forest coverage, representing significant restoring effects. The quantities of water and soil erosion of the disturbed wasteland, artificial plantation, natural restoration area and terrace land reclaimed from steep slopes were decreased by 46.9%50.1%,(49.6%)59.3%, 29.5%66.4% and 65.1%76.1% respectively within 3 years.