新疆博尔塔拉河冬季鱼类群落空间分布及其与环境因子的关系

Spatial Distribution of the Fish Community and Its Relationship with Environmental Factors in the Bortala River in Winter

为完善新疆博尔塔拉河流域的渔业生态评估及体系养护,2016年11月在博尔塔拉河流域展开资源调查,于干流设置4个监测断面,对该水域鱼类群落结构进行研究。本调查共采集鱼类1515尾,隶属于3目5科14属,共计15种,均为硬骨鱼类;通过相对重要性指数(IRI指数)获得的博尔塔拉河干流的鱼类优势种共计3种,分别为麦穗鱼(Pseudorasbora parva)、棒花鱼(Abbottinarivularis)和新疆高原鳅(Triplophysa strauchii)。基于Bray-Curtis相似性指数的二维聚类分析结果显示,在60%相似水平上空间聚类,可将博尔塔拉河分为上游及下游2组,物种聚类在50%相似水平上可分为I^IV共计4组。典范对应分析(CCA)表明,影响冬季鱼类群落空间结构的主要环境因子为海拔、温度和溶氧。对照历史资料结果表明,博尔塔拉河流域的土著鱼类种类减少;外来鱼类种类逐年增加;经济鱼种减少;鱼类群落小型化明显。本研究可为该流域生态环境评估、水资源开发利用及渔业资源养护提供基础数据,具有一定的参考价值。

Knowledge about the differences or variations in the fish community is important to assess and predict the effects of habitat loss or environment degradation on the river ecosystems.The Bortala River is an important interior river in Xinjiang,China.Although research regarding spring and summer fish communities has been reported,that regarding winter fish communities is lacking.Based on fishery resource surveys in November 2016 at the mainstream of the Bortala River,the fish community structure and diversity of the river were analyzed.The results indicated that a total of 1515 fishes were collected at 4 representative sections,which belonged to 3 orders,4 families,14 genera,and 15 species.The dominant species(IRI 1000)in the mainstream of the Bortala River were Pseudorasbora parva,Abbottina rivularis,and Triplophysa strauchii.A group-averaged hierarchical cluster based on the Bray-Curtis similarity index identified two spatial patterns of the fish assemblage at the 60%similarity level and four patterns of species composition at the 50%similarity level.The canonical correspondence analysis(CCA)suggested that altitude,temperature,and dissolved oxygen were the major environmental factors affecting the spatial patterns of fish assemblages in winter.The results of this study indicated that the species of native fish have declined,and the species of fish with low economic value have increased significantly.The aquatic ecosystem will be destroyed unless effective measures are taken to protect the native fish.Further studies are needed to investigate the mechanisms by which these factors operate together upon the fish assembles in the Bortala River in winter.