环境DNA技术与传统捕捞揭示崇明岛内河鱼类多样性

崇明岛位于长江入海口，其内河网密布，鱼类资源众多，但违规捕捞现象屡禁不止，严重影响崇明岛鱼类资源。鱼类多样性是水生态环境保护的一个重要指标，为评估上海崇明岛内鱼类资源、揭示鱼类多样性，于2020年6月至2021年5月在崇明岛内河设置24个采样位点，利用环境DNA(eDNA)技术与传统捕捞手段，每个季度进行了1次共4次采样调查。调查共检出13个目级阶元的78种鱼类，其中鲤形目最多，约占44%。基于捕获鱼类样本计算的全年香农-威纳多样性指数为2.08,基于eDNA数据计算的全年香农-威纳样性指数值为2.96,表明崇明岛具有较丰富的鱼类多样性。两种方法检测出共同的优势种为鳊(Parabramis pekinensis)、似鳊(Pseudobrama simoni)、麦穗鱼(Pseudorasbora parva)、子陵吻虾虎鱼(Rhinogobius giurinus)、大鳍(Acheilognathus macropterus),表明崇明岛内河鱼类群落结构由淡水鱼类主导。主坐标分析和PERMANOVA检验结果显示东-西部群落鱼类组成存在差异(R²=0.101 2,P=...

Integrating environmental DNA technology and traditional fish survey to reveal the diversity of fishes in the rivers on the Chongming Island

The Chongming Island is located at the estuary of the Yangtze River. There are dense rivers and abundant fish resources on the Chongming Island, however, illegal fishing continues despite prohibitions, seriously affecting the level of the fish resources. Besides, fish diversity is an important indicator for aquatic ecology conservation. For evaluating and revealing fish resources and diversity in Chongming Island in Shanghai and reveal fish diversity, a quarterly survey was conducted in 24 sampling sites in the rivers of the Chongming Island from June 2020 to May 2021 which integrated environmental DNA technology and traditional fishing method. In this survey, a total of 78 fish species were detected, covering 13 orders and the Cypriniformes was the dominant species, accounting for 44% of total species found. The annual Shannon-Wiener diversity index calculated based on fish samples was 2.08, and the annual Shannon-Wiener diversity index calculated based on environmental DNA data was 2.96 respectively, indicating that the Chongming Island is rich in fish diversity. The common dominant species identified by the two methods were Parabramis pekinensis, Pseudobrama simoni, Pseudorasbora parva, Rhinogobius giurinus and Acheilognathus macropterus, indicating that the fish community structure in the rivers of Chongming Island is dominated by freshwater fish. The Principal Coordinate Analysis and the PERMANOVA test indicated that there are differences in fish composition between the community of East and West community (R²=0.101 2,P=0.027 6). We suggest that environmental DNA technology should be used as an important supplementary means for the investigation of fish resources and diversity. This study reported the existing status of fish resources and diversity of Chongming Island and provided basic data for rational utilization and conservation of the fish resources on the Chongming Island.