黄河口及其邻近水域鱼类生态类群组成及其季节变化

Composition of Ecological Groups and Their Seasonal Changes of Fish in Yellow River Estuary and Its Adjacent Waters

根据2013—2014年在黄河口及邻近水域进行的7个航次的渔业资源底拖网调查数据,采用聚类分析和非度量多维标度排序等方法,研究了目前该水域生态环境条件下鱼类生态类群组成及其季节变化。研究表明,本次调查共捕获鱼类51种,隶属硬骨鱼纲10目27科43属;其中定居性鱼类30种,洄游性鱼类17种,河口性4种;暖温种30种,暖水种15种,冷温种6种。暖温种和定居种种数和平均网获量在各季节中均占绝对优势。春季鱼类27种,其中暖温种15种,定居性种类19种;夏季鱼类34种,暖温种和定居性种类分别为20和12种;秋季鱼类30种,暖温种和暖水种分别为16和14种,定居性种类18种;冬季鱼类15种,暖温种11种,暖水种2种,定居性种类12种。暖温性鱼类、洄游性鱼类平均网获量均在夏季最高。聚类分析和非度量多维标度排序分析表明,可将16种主要鱼类划分为A～D共4个种类群。A、B类群夏秋季在黄河口水域分布广泛,数量和质量上均占优势,该类群多为洄游性种类;C类群主要由定居种组成,各季节均有分布,春季和夏季分布较广,该类群已适应黄河口多变的环境;D类群主要为河口性鱼类,冬季较多。4个种类群平均网获量较高的站位主要集中在河口区。黄河口水域鱼类生态类群组成及其季节变化可能主要与水域温度变化、营养盐分布和鱼类洄游等有关。

It is helpful for understanding fish community structure and its dynamics to identify the composition of ecological groups.Based on the data collected from the bottom trawl surveys from June 2013 to May 2014 in the Yellow River estuary and its adjacent waters,the species composition of different ecological groups and their seasonal changes were examined using cluster analysis(CLUSTER)and non-metric multidimensional scaling(NMDS).The results showed that 51 fish species in total were identified,which belonged to 10 orders,27 families,and 43 genera.There were 30 settled fish species with their mean catch weight and number accounting for 36.00%and 29.14%of the total,respectively,four estuarine fish species and 18 migratory fish species.There were 31 warm temperate fish species,and their catch weight and number occupied 85.69%and 95.31%,respectively.There were 6 cold temperate species and 15 warm water species.The mean catch weight and number of warm temperate and migratory fish species were the highest in summer.CLUSTER and NMDS analyses showed that 16 main fish species were classified into four species-groups.The A and B groups widely distributed in the Yellow River estuary in summer and autumn,and most of them were migratory.The C group as mainly composed of settled fish species,and widely distributed in spring and summer.The D group was mainly estuarine fish species and more fish species were caught in winter.The stations with higher mean catch weight and number for the four groups were mainly concentrated in the estuary area.The fish groups adapted to the ecological environments in the Yellow River estuary.In general,the seasonal variation of eco-groups and species compositions in the Yellow River estuary and its adjacent waters may be affected by the changes of water temperature,nutrient distribution and fish migration.