金沙江中游水电建设因其对流域生物多样性的影响受到社会各界广泛关注。应用景观生态学方法,选择淹没区面积、斑块数、景观多样性、均匀性、聚集度、蔓延度、形状指数、分维数等指数,构建了由10个一级指标、14个二级指标组成的景观多样性影响评价指标体系,对金沙江“虎跳峡-旭龙河”段适宜水电建设的龙盘、塔城和其宗3个坝址、5套建设方案淹没区景观层次生物多样性的影响进行了比较研究。结果显示,江段往下游方向,景观多样性、均匀性、连通性逐渐降低、破碎化程度加剧;各方案对陆地生物多样性保护价值的影响:其宗下坝〉其宗上坝〉塔城坝〉龙盘高坝〉龙盘低坝。研究结果为深入评价金沙江中游水利水电开发的生物多样性影响提供了借鉴和基础。
The environmental impacts of the proposed hydro-stations on the Upper Yangtze River (also known as Jinsha River),Yunnan,China have aroused widely public concerns. In this paper,a landscape lew el biodiversity impact assessment system with 10 first and 14 second order indices including total area to be flooded,vegetation cover,landscape diversity and evenness, aggregation index, contagion index, shape index,fractal index, etc. was set up to assess the biodiversity impacts of the proposed five construction schemes of the three darns from the"Tiger Leap Gorge'to the"Xulong River", along the Upper Yangtze River. A quantified comparison study from three aspects of landscape level diversity-respectively the type, patch and pattern diversities was carried out. Results showed that the five flooding area's landscape diversity and connectivity decreased toward downstream;however, the landscape fragmentation increased. The order of the five sites according to their biodiversity impacts was.. Qizong lower-dam scheme〉Qizong upperdam scheme〉Tacheng dam scheme〉Longpan high-dam scheme〉Longpan low-dam scheme. This conclusion wilt provide a scientific basis for further biodiversity impact studies and decision-making of hydropower development in the Upper Yangtze catchments.