关键词: 游泳生物, 种类组成, 数量分布, 龙海市东南部海域, nektons, species composition, quantitative distribution, the southeastern waters of Longhai City

Abstract: The species composition of nektons in the southeastern waters of Longhai City were preliminary studied in this paper based on the single trawl surveys in two voyages in 2012. The results showed that a total of 155 nekton species were discovered in the studied area, including 96 fish, 29 crab, 22 shrimp and 8 cephalopod. The weight and individual density of nektons obtained from August to September were 868.00 kg/km2 and 134.51×103 ind./km2, which were far greater than the densities acquired in April (176.12 kg/km2 and 22.12×103 ind./km2). The average species diversity indexes of the weight and individual density were at relative high level, of 3.30 and 3.26. Two dominant species Parapenaeopsis cultrirostris and Parapenaeopsis hardwickii were recorded in the two cruises. Finally compared with the fishery resources data from Jiulong River Estuary, the results in this study presented a few more nekton species, larger individual density and higher species diversity.