The understanding of patterns in fish assemblages is imperative for management and conservation plans. There is a dearth of information on the environmental factors affecting the fish community structure in the reservoirs built on the intermittent rivers of India. We hypothesized that the environmental factors most likely influenced the patterns in the structure of fish diversity at temporal and spatial scales in a subtropical reservoir of the Ganga River basin. The data was gathered seasonally from April 2017 to March 2018 from three sites each in the riverine, transitional, and lacustrine zones of the reservoir. About 16,220 fish specimens were captured that belonged to 7 orders, 14 families, 31 genera, and 40 species. The diversity indices showed the highest diversity in the riverine and the lowest in the lacustrine zones of the reservoir. At a temporal scale, the highest diversity was observed in the monsoon season and lowest during the summer season. The cluster analysis spatially separated the fish fauna into three groups, each group formed by sampling sites in the riverine, transitional and lacustrine regions of the reservoir and may have resulted from physico-chemical and anthropogenic influences. Our study suggests the need to consider the possible influence of altered environmental conditions on fish assemblage, and some recommendations were suggested for the improvement of the fisheries impacted by the construction of dams.

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评估环境因素对恒河流域未开发的亚热带 Jargo 水库鱼类群落和空间多样性的影响

了解鱼类群落模式对于管理和保护计划至关重要。关于影响印度间歇河流水库中鱼类群落结构的环境因素的信息匮乏。我们假设环境因素最有可能影响恒河河流域亚热带水库时空尺度上鱼类多样性结构的模式。这些数据是从 2017 年 4 月到 2018 年 3 月从水库的河流、过渡和湖泊区域的三个地点季节性收集的。共捕获鱼类标本约16220条，分属7目14科31属40种。多样性指数显示，水库河流区多样性最高，湖区多样性最低。在时间尺度上，季风季节的多样性最高，夏季的最低。聚类分析在空间上将鱼类动物群分为三组，每组由水库河流、过渡和湖泊区域的采样点组成，可能是物理化学和人为影响的结果。我们的研究表明需要考虑改变的环境条件对鱼类群落的可能影响，并提出了一些改善受大坝建设影响的渔业的建议。储层的过渡和湖泊区域，可能是由物理化学和人为影响造成的。我们的研究表明需要考虑改变的环境条件对鱼类群落的可能影响，并提出了一些改善受大坝建设影响的渔业的建议。储层的过渡和湖泊区域，可能是由物理化学和人为影响造成的。我们的研究表明需要考虑改变的环境条件对鱼类群落的可能影响，并提出了一些改善受大坝建设影响的渔业的建议。