滦河流域鱼类群落结构空间异质性与影响因子分析

掌握鱼类群落结构与环境因子的关系是河流鱼类多样性保护与恢复的基础.基于2016年10月对滦河流域58个采样点的调查数据，通过聚类分析法及NMS（非度量多维标度法，non-matric multidimentionalscaling）分析了滦河鱼类群落空间格局特征，并采用典范对应分析（CCA，canonical correspondence analysis）探讨了影响鱼类群落结构的环境因子.调查期间共采集鱼类15科41属49种，鲤科鱼类最多，为23种.研究表明:①聚类分析发现鱼类空间分布可分为3组，第1组集中在滦河干流中下游及支流汇入干流附近河段，第2组集中在冀东部独流入海的河流，第3组集中在滦河干支流的中上游河段.②NMS结果也证明3组在空间分布上差异明显，第2组与第3组之间没有重叠.③物种数、Shannon-Wiener多样性指数、Margalef丰富度指数和Simpson多样性指数在第1组与第3组之间存在显著差异，而Simpson多样性在第2组与第3组之间也存在显著差异.④单因素方差分析（one-way ANOVA）显示，第1组与第2组、第3组相比，水温与两组之间都有显著性差异，第2组与第1组、第3组之间在电导率、TDS（总溶解固体）、栖境复杂性、速度-深度结合、堤岸稳定性和河水水量状况有显著性差异.⑤典范对应分析发现，影响滦河流域的环境因子包括TDS、浊度、pH与水温等4个水体理化参数以及底质与堤岸稳定性2个栖息地质量参数.研究显示，基于对滦河流域鱼类空间异质性和相关环境影响因子的理解，可为该流域鱼类多样性保护及管理对策制订提供方向. 

Analysis of Fish Community Spatial Heterogeneity and Its Driving Factors in the Luanhe River Basin

Understanding the relationship between fish assemblages and environmental factors is the basis for the protection and restoration of fish diversity in river ecosystem. The spatial pattern of fish community in the Luanhe River Basin was analyzed by the cluster analysis and non-matric multidimentional scaling (NMS), and the environmental factors that affected fish community structure were discussed by canonical correspondence analysis (CCA) based on the survey data of 58 sampling sites in the Luanhe River Basin in October, 2016. A total of 49 fish species belonging to 15 families and 41 genera were collected from all sampling sites. The fish of Cyprinidae contained 23 species. The main results showed as follow:(1) Cluster analysis showed that there were three different groups of fish distribution or fish assemblage. The sites in the first group located at the middle and lower reaches of the Luanhe River stem and the confluence reaches of the tributaries. The sites in the second group located at the eastern rivers of the HebeiProvince, which flowed into the sea independently. The sites in the third group located at the middle and upper reaches of the stem and tributaries. (2) The results of NMS also exhibited that the ordination of three groups was a differential pattern, in which group 2 was separated from group 3 obviously. (3) Four fish community indices such as species richness, Shannon-Wiener diversity index, Margalef richness index and Simpson diversity index showed significant differences between group 1 and group 3, while Simpson diversity index also showed significant differences between group 2 and group 3. (4) One way analysis of variance showed that group 1 was significantly different from group 2 and group 3 at water temperature. There was a significant difference between group 2 and group 1, and group 3 in conductivity, total dissolved solids, habitat complexity, velocity-depth combination, embankment stability and river water quality. (5) The results of CCA analysis showed that four water quality parameters including pH, turbidity, water temperature and total dissolved solids and two habitat quality parameters such as substrate conditions and embankment stability were the key environment factors which affected fish community significantly. The well understanding on the characteristics of fish spatial heterogeneity and its influencing factors can provide a clear goal on the fish diversity conservation and management strategies formulation.