信江上游鱼类资源及物种多样性分析

2016年6月底～2019年7月中旬,对信江上游及其支流的鱼类资源进行了系统地调查。共采集到野生淡水鱼类66种,隶属于5目16科50属,其中以鲤形目鱼类种类最多,共计3科34属45种,占总采集种类数的68.2%;科级水平以鲤科占优势,共有39种,占总种类数的59.1%;鳅科和鲿科各5种,分别占7.6%;鮨科、塘鳢科、虾虎鱼科和太阳鱼科各两种,分别占3.0%;其他9科各1种,共占13.6%。鱼类生态类型以湖泊定居型鱼类、杂食性占优。这些鱼类隶属于五个区系复合体,以江河平原区系复合体和南方平原区系复合体为主,分别占种类数的40.9%和24.2%。在调查过程中采集到食蚊鱼、斑点叉尾鮰、太阳鱼及大口黑鲈等外来养殖品种,这些鱼多为凶猛肉食性鱼类,严重威胁土著鱼类的生存繁殖,需加强监管。

FISH RESOURCE INVESTIGATION AND SPECIES DIVERSITY ANALYSIS OF THE UPPER REACH OF XINJIANG RIVER IN JIANGXI PROVINCE

A survey of fish resources in the upper streams of Xinjiang River was systematically investigated from June 2016 and July 2019. A total of 66 freshwater fish species belonging to 5 orders, 16 families and 50 genera were obtained. Cypriniformes, which contained a total of 3 families, 34 genera and 45 species, and accounted for 68.2% of the total fish species, was the dominant fish fauna. Among which, Cyprinidae was the dominant family, with 39 species, accounting for 59.1% of the total fish species; Cobitidae and Bagridae, with 5 species each, accounting for 7.6%, respectively; Serranidae, Eleotridae, Gobiidae and Anabantidae, with 2 species each, accounting for 3.0%, respectively; other 9 families, with 1 species each, totally accounting for 13.6%. Lake resident species made up a large proportion of the total fish collected, omnivorous fishes were the most abundant. According to the fauna analysis, the 66 fish species could be divided into five fauna complexes system. There were more species in the southern plain fish fauna complex and the river plain fauna complex, accounting for 40.9% and 24.2% of the total species, respectively. In the process of this research, specimens belonging Gambusia affinis, Letalurus punetaus, Lepomis gulosus and Micropterus salmoides were collected. Most of these species were fierce predatory fish, which could seriously threaten the survival and reproduction of indigenous fish species, and need to be strictly supervised and controlled.