浑河流域2010-2014年的鱼类群落和水生态健康变化分析

为了解浑河流域鱼类群落结构的变化趋势和水生态健康变化，分别于2010年和2014年对浑河流域46个采样点进行了鱼类和环境因子调查。其中2010年采集到鱼类15039尾，隶属于6目9科32种；2014年采集到鱼类10483尾，隶属于6目10科41种。Mann-Whitney U检验表明从2010年到2014年鱼类总物种数、香农多样性指数、底层物种数百分比、植食性和肉食性个体数百分比等鱼类特征参数显著上升。典型对应分析（CCA）结果表明，2010年显著影响鱼类群落结构的环境因子为流速、电导率、河流等级和钙离子浓度；而2014年显著影响鱼类群落结构的环境因子则为电导率、河流等级和氨氮浓度。2010年和2014年的鱼类完整性指数（FIBI）评分分别为48.7624.82和50.4117.35，与2010年的评价结果相比，2014年F-IBI结果稍有改善，其中极好和好的点位数分别少3个和1个，一般的点位数多9个，而极差和差的点位分别少4个和1个。

VARIATION OF FISH COMMUNITY STRUCTURE AND WATER SYSTEM CONDITIONS FROM 2010 TO 2014 IN HUN RIVER OF LIAONING PROVINCE,NORTHEAST PART OF CHINA

To understand the structure variation of fish assemblage of Hun River Basin in Liaoning Province of Northeast China, 46 sampling sites were investigated in 2010 and 2014. A total of 32 species and 15039 fish, belonging to 9 families and 6 orders, and 41 species and 10483 fish, belonging to 10 families and 6 orders, were identified in 2010 and 2014, respectively. The Mann-Whitney U test supported a significant increase in fish assemblage parameters like the number of fish species, Shannon-Wiener index, proportion of benthic species, proportion of herbivores individuals and proportion of carnivores individuals. Canonical correspondence analysis showed that in 2010, flow rate, conductivity, river rank and calcium ion were the primary environmental factors affecting fish assemblage, while in 2014, conductivity, river rank and ammonia significantly affect fish assemblage. The score of F-IBI were 48.7624.82 and 50.4117.35 in 2010 and 2014 respectively. By contrast in 2014, the health condition slightly increased and the sampling sites of very poor, poor, good and excellent decreased by 4, 1, 1 and 3 sites than those in 2010, respectively. Meanwhile, the sampling sites of moderate increased by 9 sites than those in 2010.