长江上游支流南广河的鱼类多样性及资源现状

南广河是长江上游一级支流, 为全面了解该河流的鱼类多样性, 作者于2017年11月至2018年9月在南广河干流及支流28个采样点进行了6次调查, 共采集鱼类64种, 隶属于5目13科48属, 其中四川省重点保护鱼类有鲈鲤(Percocypris pingi)和岩原鲤(Procypris rabaudi) 2种, 长江上游特有鱼类17种, 列入《中国脊椎动物红色名录》的濒危和易危的鱼类有9种。南广河现有分布鱼类以小型种类为主, 宽鳍鱲(Zacco platypus)和鲤(Cyprinus carpio)为优势种。南广河鱼类多样性总体较高, Margalef丰富度指数、Shannon-Wiener多样性指数、Simpson优势度指数及Pielou均匀度指数分别为6.57、3.10、0.93、0.74; 中游河段的鱼类种类和数量较丰富, 分别占渔获物总种类和总数量的65.63%和28.98%; 支流镇舟河的鱼类种类和数量也较丰富, 分别占37.50%和20.48%。南广河不同河段的鱼类种类组成具有明显差异, 大坝建设和过度捕捞可能影响了鱼类分布并导致其资源量下降。

Fish diversity and resource status in the Nanguang River,a tributary of upper Yangtze River

Nanguang River is a tributary of upper Yangtze River that provides important resources and food to various communities. To understand the current status of fish diversity within Nanguang River, we sampled the river and its primary tributaries six times from November 2017 to September 2018. A total of 64 fish species were collected, two of which (Percocypris pingi and Procypris rabaudi) are protected fish in Sichuan Province, 17 species were endemic to the upper Yangtze River, and 9 were listed as endangered or vulnerable species in Red List of China’s Vertebrates. The most dominant fish were small in size, of which Zacco platypus and Cyprinus carpio were most dominant. Additionally, the Nanguang River fish community possess considerable diversity based on Margalef species richness index, Shannon-Wiener diversity index, Simpson dominance index, and Pielou evenness index values. While there are obvious differences in fish composition across different reaches of the Nanguang River, dam construction and overfishing may have considerably impacted fish distribution and fish resources, the results of which our investigation presents.