黄河口海域春季和夏季须子网渔获物组成分析

须子网是黄河口海区应用较广的陷阱类网具之一。为养护和管理黄河口海区渔业资源,对该海域春季和夏季须子网渔获物组成进行分析。2013年5月和2014年8月对东营黄河口海区进行了3次导陷插网网具须子网的渔获物调查,采用相对重要性指数(IRI)、种类丰富度指数和Sorensen相似性系数Ss对调查数据进行了分析。结果显示,春季和夏季须子网捕获渔获物共计45种;春季和夏季渔获物优势种(IRI1 000)分别为7种和9种,共同优势种为2种;春季和夏季渔获种类的Sorensen相似性系数Ss为0.39,该海域春季和夏季的渔获物丰富度指数(R)、Shannon-Wiener多样性指数(H)、均匀度指数(J)分别为15.81和2.91、0.51和11.26、2.17和0.43;春季和夏季平均每网渔获量和尾数分别为55.04 kg和8 766尾、50.56 kg和3 390尾。调查结果表明,春季生物群落优势度较夏季优势高,使用须子网,其渔获物组成混杂、渔获幼体组成比例较高,长此以往不利于资源的繁殖保护,对黄河口渔业资源破坏较为严重。调研结果可为我国黄河口海区渔具管理以及渔业资源的可持续发展与管理提供科学参考。

Analysis on the catch composition of XuZi net at Yellow River estuary in spring and summer

XuZi net is one kind of the trap nets that are widely used in Yellow River estuary area.For the better conservation and management of fishery resources in Yellow River estuary area, the species compositions of catches with XuZi nets in spring and summer were analyzed.Based on the data obtained from three investigations into the catch composition of Yellow River estuary with XuZi nets in May 2013 and August 2014, indices of Sorensen similarity (Ss), species richness (R), Shannon2-Wiener diversity (H), evenness ( J) and index of relative importance ( IRI) were calculated.The results showed that there were altogether 45 species in the catches of spring and summer; the numbers of dominant species ( IRI>1 000 ) in spring and summer were respectively 7 and 9, with 2 species in common;the Sorensen similarity coefficient between the catch compositions of spring and summer was 0.39;the indices of R, H and J of the catches were respectively 15.81, 2.91, and 0.51 in spring and 11.26, 2.17, and 0.43 in summer;and the average catch biomass and catch weight were 8 766 ind/net and 55.04 kg/net in spring, and 3 390 ind/net and 50.56 kg/net in summer.The results showed that the biodiversity level in spring was higher than that of summer, and in spring, the catch composition of XuZi net was complex and with a high percentage of young individuals, which would exert adverse effects on fishery resources protection in the long run.The data provided a scientific reference for fishing gear management and sustainable fishery development in Yellow River estuary area.