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长江靖江段位于长江河口的近口段,每天有两涨两落的不规则半日潮,是国家级水产种质资源保护区,在渔业资源养护中起着重要作用。为了弄清靖江段沿岸水域鱼类群聚的组成特点及其丰度生物量变化,我们于2002–2011年对靖江沿岸秋季的鱼类群聚作了调查。结果显示,10年间79个样本共有鱼类91种,隶属于12目23科,其中鲤形目47种,鲈形目17种,鲇形目10种;从生态类型来看,洄游鱼类4种,河口鱼类13种,淡水鱼类74种。10年间,平均每年秋季出现鱼类47种,平均Jaccard物种相似性系数仅53.72%,处于中等相似水平。IRI≥100的优势种和常见种合计有42种,年均19种,占当年数量的92.26%。贝氏(Hemiculter bleekeri)、似鳊(Pseudobrama simony)、光泽黄颡鱼(Pseudobagrus nitidus)等小型种类,以及翘嘴鲌(Culter alburnus)、鳊(Parabramis pekinensis)、瓦氏黄颡鱼(P.vachellii)等中型种类的幼体是优势种和常见种的主体,整个鱼类群聚的个体均重仅6.99 g。丰度生物量曲线显示,除2010年外的其他年份,第一优势种均为极小型鱼类,2002–2009年的前面几个优势种也是小型鱼类,仅2010和2011年有几种较大体型的种类加入到主要优势种行列。研究还显示,最近10年来,靖江沿岸水域秋季整个鱼类群聚的生物量、个体均重以及62%的优势种与常见种的种群数量,在总体上有随年份而增加的趋势,这预示着这一水域渔业资源可能已改善。
The Jingjiang section of the Yangtze River, located near the mouth of the Yangtze River estuary, has two half-days of irregular tidal waves rising and falling each day. It is a national aquatic germplasm reserve and plays an important role in the conservation of fishery resources. In order to understand the compositional characteristics of fish assemblages and the abundance of biomass in the coastal waters of Jingjiang section, we investigated the clustering of fish in the autumn along Jingjiang River from 2002 to 2011. The results showed that there were 91 species of fish belonging to 12 orders and 23 families in 79 samples in 10 years, including 47 species of Cypriniformes, 17 species of Perciformes and 10 species of Ephemeroptera. In terms of ecological types, migratory fish 4 Species, 13 species of estuarine fish, 74 species of freshwater fish. During the 10 years, 47 species of fish appeared in autumn each year. The average similarity coefficient of Jaccard species was only 53.72%, which was at medium level. There are 42 kinds of dominant species and common species with IRI≥100, with an average of 19 species each year, accounting for 92.26% of the total number of the same year. Hemiculter bleekeri, Pseudobrama simony, Pseudobagrus nitidus, and other small species such as Culter alburnus, Parabramis pekinensis, P. vachellii ) And other mid-sized species of larvae are the dominant species and common species of the main body of the entire population of fish weighing only 6.99 g. Abundance biomass curves show that the first dominant species are all minipigs except for the year 2010, and the first few predominant species from 2002 to 2009 are also small fish species. In 2010 and 2011 alone, there were several more The main types of species added to the ranks of the dominant species. The study also showed that in the recent 10 years, the biomass of the entire fish assemblage, individual weight and the population of 62% of the dominant species and common species in the autumn waters of the Jingjiang River waters generally showed an increasing trend with age, which indicates The fisheries resources in this area may have improved.