中文摘要：

根据2009-2012年在金沙江干流攀枝花雅砻江河口至格里坪镇江段的渔获物调查,对该区域的鱼类种类组成和群落结构进行了分析。共收集到鱼类60种,隶属于3目10科37属,各年种类数呈逐年减少的趋势。聚类分析方法对各年间的种类组成的分析结果表明：4年的鱼类种类组成可以分为2个类群：类群I包括2009年和2010年,类群II包括2011年和2012年;单因素的相似性分析表明2个类群之间在统计学上无显著性差异（R=1,P=33.3%〉0.05）。生物多样性分析结果表明,2010年后攀枝花江段鱼类的Margalef丰富度指数、ShannonWiener多样性指数以及Pielou均匀度指数均有所下降。CA方法对4年间的鱼类群落结构的时空分布格局的分析结果表明：4年的鱼类群落结构分为2个类群：类群I包括2009年和2010年,类群II包括2011年和2012年,但one-way ANOSIM分析表明2个类群之间在统计学上无显著性差异（R=0.92,P=27.6%〉0.05）。SIMPER分析的结果表明,4年间丰度减少的种类多为喜流水性的鳅科鱼类和大型冷水性鱼类,而丰度增加的种类为喜流水的2种鮈亚科鱼类以及喜静、缓流生境的2种小型鱼类。

英文摘要：

Water resource development on the Jinsha River could have profound effects on the fish resources. With the construction of Guanyinyan hydropower station and the impoundment and operation of Xiangjiaba and Xiluodu hydropower stations in the middle reach of Jinsha River,the Panzhihua reach has become an important habitat for fish species adapted to running water. This study focused on the composition,diversity and community structure of fish species in this region. The results will help characterize and conserve the fish resources in this reach,provide essential information for the sustainable use of the fishery resource and assess the ecological impacts produced by the hydropower projects in the middle and lower reaches of the Jinsha River. Investigations were made on the fish catches from the main stream of the Jinsha River（ from Yalong River estuary to Geliping town in Panzhihua city）from 2009 to 2012. Three sample sites（ Geliping,Qingxiangping and Yalong River estuary） were selected and 156 fish catches,collected mainly by gillnets and hooks,were examined. Fish samples were identified according to The Fish of Sichuan and other literature resources and full length,body length and body weight were measured for each individual. The data was then used to analyze temporal patterns of species composition and fish community structure. A total of 60 fish species,belonging to 3 orders,10 families and 37 genera were identified during the four year study period and the number of fish species decreased each year. Cluster analysis（ CA） showed that fish species composition could be divided into two groups： Group I（ 2009- 2010） and Group II（ 2011- 2012）,but one- way analysis of similarity（ one-way ANOSIM） indicated no significant difference between Group I and Group II（ R = 1,p = 33. 3% 〉0. 05）. The biodiversity analysis of fish community showed that Margalef richness index（ R）,Shannon-Wiener diversity index（ H） and Pielou evenness index（ E） all decreased after 2010. The analysis on