关键词: 游泳动物, 种类组成, 群落结构, 九龙江口, nekton, species composition, community structure, Jiulongjiang Estuary

Abstract: Based on the data of fish resource survey from Jiulongjiang Estuary in spring（April）and autumn（November）2013, the nekton species composition, floristic characteristics, community structure and biodiversity were analyzed. The results showed that there were 76 kinds of nekton in Jiulongjiang Estuary in spring and autumn, belonging 16 orders, 40 families and 59 genera, including 41 fishes, 15 crabs, 13 shrimps, 4 squillas and 3 cephalopods. The warm waters species were most in fishes, as well as the demersal and near-bottom fishes; there were 6 kinds of dominant species in spring and 3 kinds of dominant species in autumn, which were important economic species, indicating a good community structure; the resource densities in weight in spring and autumn were 252.3 kg/km2 and 402.5 kg∕km2 respectively, on a low level; the biodiversity of nekton in spring was higher than the one in autumn, but both of the biodiversity were at a low level.