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采用2010年11和2011年5月苏北浅滩海域2个航次的渔业资源调查资料,研究苏北浅滩虾类资源密度、种类组成和优势种,结合该海域沙脊潮沟系统,探讨了地形特征和潮流对虾类数量分布的影响。结果表明:两次拖网调查共鉴定虾类15种;依据相对重要性指数IRI值,得出该海域春季优势种为细螯虾(Leptochela gracilis),秋季为中国毛虾(Acetes chinensis);春季虾类生物量和尾数密度均高于秋季,春季和秋季虾类生物量分别为35.64和9.24kg·km-2,尾数密度分别为35.42×103和25.92×103ind·km-2;根据贡献率β值,虾类总密度变化与主要优势种虾类密度变化密切相关,两者平面分布规律也一致;因苏北浅滩海域潮沟和沙脊相间的地形地貌特征,加之受东海前进波和黄海旋转波作用,形成潮流从北、东、南3个方向向心辐聚作用;潮沟的流速大于沙脊的流速,致使无论在春季还是秋季,形成虾类生物量和尾数密度在潮沟内远大于沙脊上、在沙脊与潮间带浅滩之间的深槽处略高于沙脊处的分布特征。
Based on the survey data of fishery resources of two voyages in shallow shoal of northern Jiangsu in May 2010 and May 2011, the density, species composition and dominant species of Shrimp shoal in northern Jiangsu were studied. Based on the Shaji tidal ditch system in this area, the topographical characteristics And the trend of shrimp species distribution. The results showed that 15 species of shrimp were identified by two trawl surveys. Based on the relative importance index (IRI), the dominant species of spring was Leptochela gracilis in spring and Acetes chinensis in autumn. The biomass and mantissa densities were all higher than those in autumn, while the shrimp biomass in spring and autumn were 35.64 and 9.24 kg · km-2, respectively. The mantissa densities were 35.42 × 103 and 25.92 × 103ind · km-2, respectively. According to the contribution rate β , The change of total shrimp density was closely related to the density change of main dominant species of shrimp, and the plane distribution law of the two shrubs was also consistent. Due to the topographic and topographical features of tidal flats and sand ridges in the shallow shoal of northern Jiangsu combined with the rotation of the East China Sea and the Yellow Sea , Forming a tidal current converging towards the heart from the north, east and south directions. The velocity of the tidal channel is greater than that of the sand ridge, resulting in the formation of shrimp biomass and mantissa density much greater than sand in the tidal channel, both in spring and autumn Ridge, in the deep groove between the sand ridge and intertidal shoal slightly higher than the sand ridge distribution.