Community Structure and Diversity of Fish in the Middle Reaches of Ganjiang River
Ganjiang river is the largest tributary of Poyang Lake,and it is also an important habitat and breeding site for fish.With the gradual establishment and operation of Ganjiang river cascade hub,the conditions of fish habitat and reproduction have changed.In order to grasp the characteris-tics of fish community structure in the middle reaches of the Ganjiang river,understand the impact of the main cascading Xiajiang water conservancy project on fish resources,and accumulate basic data for the upcoming total ban on fishing in the main stream of the Ganjiang river,a survey of fish re-sources in the middle reaches of the Ganjiang river was carried out in 2022.A total of 77 fish spe-cies were investigated,belonging to 5 orders,11 families and 49 genera,among which the number of carp fish species was the largest,accounting for 64.94%.The dominant species are Squalidus ar-gentatus,Hypophthalmichthys nobilis,Pseudobrama simoni and Parabramis pekinensis.There are ob-vious differences in fish communities in different waters.On the whole,the lower part of Xiajiangba has the highest level of fish diversity,mainly due to the fact that it is close to the four fish germ-plasm resources reserve of Xiajiang Section,which has been completely banned from fishing.At the same time,this part of the river still maintains natural water characteristics during most of the time,which can meet the habitat and breeding needs of different types of fish,so it is recommended to fo-cus on protection.
fish communityenvironmental impact factorsfish diversitymiddle reaches of Gan-jiang river