浑河流域鱼类群落特征及其与环境因子的关系

流域水生态调查是对受损的流域水生态系统进行恢复的基础。以浑河流域为例，对全流域62个采样点的鱼类群落进行调查。共采集并鉴定出鱼类34种，隶属于7目10科29属。其中，鲤科鱼类个体数占比最高(88.5%)，鳅科次之(6.7%)。依据鱼类群落组成的相似性，利用聚类分析将62个采样点分为3组：组Ⅰ主要分布于浑河上游；组Ⅱ主要分布于浑河中游的各支流；组Ⅲ主要分布于浑河中下游的干流及各支流。指示物种分析结果显示：组Ⅰ指示物种为洛氏鱥、北方条鳅、北方花鳅和中华多刺鱼；组Ⅱ指示物种主要为鲫、麦穗、宽鳍鱲等中度耐污种；组Ⅲ指示物种为餐条。典型对应分析(canonical correspondence analysis，CCA)结果表明：影响浑河流域鱼类群落结构的主要环境因子为海拔、河流等级、悬浮物(SS)浓度、森林用地比例、农业用地比例和总溶解性固体(TDS)浓度。

Fish Community Structure and Its Relationship with Environmental Variables in Hun River Basin of Liaoning Province

River ecosystem investigation is the basis for the recovery of impaired river ecosystem. Taking the Hun River Basin in Liaoning Province of Northeast China as study area, 62 sampling sites were investigated. A total of 34 species, belonging to 29 genera, 10 families and 7 orders, were identified. They were dominated by species of Cyprinidae and Cobitidae, and these two orders accounted for 88.5% and 6.7% of the total amount of fish captured, respectively. Three groups were distinguished by the cluster analysis according to the similarity of fish community structure. The first group is in the upstream of Hun River, dominated by Phoxinus lagowskii, Nemachilus toni, Cobitis granoei. The second group is in the tributaries of its midstream, with moderate tolerance species, such as Carassius auratus, Pseudorasbora parva, Zacco platypus as indicator species. The last group is in the mainstream and tributaries at its middle and lower reaches, and the indicator species of this group is Hemiculter leucisculus. The canonical correspondence analysis (CCA) showed that the altitude, river level, suspended solids (SS), percentage of forest area, percentage of farmland area, and total suspended solids (TDS) were the primary environmental factors affecting the fish community in the basin.