长江口九段沙湿地潮沟鱼类组成及其多样性

Fish species composition and diversity in intertidal creek of Jiuduansha wetland in the Yangtze River estuary

长江口九段沙湿地潮沟鱼类组成有着典型的长江口鱼类区系特征,为了解该湿地尤其是湿地潮沟鱼类的组成和多样性,在2009至2010年间对九段沙湿地的上沙、中沙和下沙潮沟进行了5次调查,共捕获鱼类3 637尾,105 158.9 g,42种,分别隶属于11目、22科。其中种类和个体数均以鲈形目居多,有20种,3 433尾,其次是鲤形目7种,49尾和鲱形目5种,33尾;海水、河口、淡水、洄游4种生态类型的种类所占百分比分别为26.19%、40.48%、23.81%、9.52%,而河口性鱼类的个体数和总湿重占绝对优势,分别占总量的94.4%和96.3%。上沙、中沙和下沙的渔获量分别为21种742尾51 025.2 g、30种1 007尾29 427.5 g、20种1 888尾24 696.2 g,均是河口性鱼类占绝对优势;就相对多度、相对重要性指数来看斑尾刺虾虎鱼(Acanthogobius ommaturus)、(Liza haermatochiel)、四指马鲅(Eleutheronema tetradactylu)这3个种类为优势种,尤以斑尾刺虾虎鱼占绝对优势;就多样性来看,上沙的多样性水平较九段沙湿地的整体水平低,鱼类种类相对较少。

The fish composition of intertidal creek of Jiuduansha wetland in the Yangtze River estuary has the typical ichthyofauna trait of Yangtze River estuary.To comprehend the fish species composition and diversity of this wetland especially the intertidal creek,we surveyed the creek of Shangsha,Zhongsha and Xiasha five times from 2009 to 2010.A total of 3 637 tails with 105 158.9 g and 42 species were captured,these species belonging to 11 orders and 22 families.The fishes number and species number of Perciformes are the highest,with 20 species,3 433 tails,next,Cypriniformes and Clupeiformes with 7 species,49 tails and 5 species,33 tails respectively.The percentage of marine species is 26.19%,estuarine species is 40.48%,freshwater species is 23.81% and diadromous species is 9.52%.The number of fishes（94.4%） and wet weight（96.3%） of estuarine species both were absolutely dominant.The catch in Shangsha,Zhongsha and Xiasha were 21 species with 742 tails 51 025.2 g,30 species with 1 007 tails 29 427.5 g and 20 species with 1 888 species 24 696.2 g respectively.Most of them were estuarine species.According to the relative density（RD） and relative significance index（IRI）,it shows that Acanthogobius ommaturus,Liza haermatochiel and Eleutheronema tetradactylu were dominant species,especially the Acanthogobius ommaturus has the absolute advantage.As for diversity,the diversity in Shangsha is lower than the Jiuduansha wetland overall level.There are relatively fewer fish species here.