珠江广州河段鱼类资源调查OA

To assess the current status of fish resources and better protect fish genetic resources in the Guangzhou Reach of the Pearl River,a survey was conducted in 2021 using gill nets and ground cages in three representative sec-tions during the dry(March),wet(July),and level(November)seasons.A total of 102 species of fishery organisms were identified and classified into 13 orders,42 families,and 79 genera.Cypriniformes and Perciformes were the domi-nant orders.In the analysis of fish species composition,the relative importance index(IRI)highighted that alien spe-cies from the Liuxi River and the confluence of the Zengjiang River Northern Main tream have become local dominant species.Additionally,low-value and small-sized fishes were the main dominant species in the Pearl River Estuary.The Shannon-Wiener index(H′),Pielou index(J′),and Margalef index(D)ranged from 2.28～3.42,0.56～0.73,and 1.61～4.11,respectively,indicating moderate to good levels of biodiversity.These values indicated that fish resources in the Guangzhou Reach of the Pearl River are relatively abundant,with a well-maintained biodiversity structure,evenly distributed populations,and a relatively stable community structure.Over all analysis suggestd that fish resources in the Guangzhou Reach of the Pearl River were challenges includingspecies decline,individual minia-turization,and significant invasion by alien species.It was recommended to continue implementing the fishing ban pe-riod,scientifically enhance stock release,and increase public awarenessof scientific release practices,among other measures,to strengthen the management and conservation of fishery resources.[Chinese Fishery Quality and Stand-ards,2025,15(2):32-42].