江苏近岸海域鱼类组成和群聚时空变化

Species Composition and Spatial-Temporal Patterns of Fish Assemblages in Jiangsu Coastal Waters

摘要: 渔业资源修复工程主要在近岸海域实施，而该工作有效进行的前提之一是充分掌握相关区域的资源和环境状况。文章基于2014年春季(5月)、夏季(8月)和秋季(11月)在江苏近岸海域的底拖网调查数据，采用相对重要性指数(IRI)和基于标准化丰富矩阵的聚类排序分析方法，对该区域的鱼类组成和生态类型、优势种组成和变化及群聚时空格局进行了深入研究。结果共采集鱼类78种，隶属2纲14目41科69属，其中石首鱼科、鳀科和虾虎鱼科是种类数量最为丰富的科目，秋季(60种)采集到的种类数明显多于春、夏季(皆为49种)。生态类型方面，3个季度总体上暖水种(41种)多于暖温种(37种)；春季底层鱼类较中上层和近底层鱼类为多，而夏秋季则以近底层鱼类为主。鮸Miichthys miiuy在3个季度皆为优势种，小黄鱼Larimichthys polyactis是春、夏季的优势种，棘头梅童鱼Collichthys lucidus是夏、秋季的鱼类优势种，而凤鲚Coilia mystus、赤鼻棱鳀Thryssa kammalensis和银鲳Pampus argenteus皆为单一季度优势种。各季度间种类更替率均值0.467 ± 0.025。江苏近岸海域鱼类群聚存在显著的时空差异：空间差异度最大的是春季，其次是夏季，秋季最小；基于群落组成聚类可将江苏近岸海域鱼类群落分为苏北、海州湾和苏中南以及苏南4种典型群落。

Abstract: Resource enhancement programs usually take place in coastal areas only based on fully under-standing of resource and environment background in related waters. Hence seasonal bottom trawl investigations were carried out in May, August and November of year 2014. Index of relative importance (IRI) as well as multivariate analysis based on abundance matrix was used in order to find out fish species composition status and spatial-temporal patterns fish assemblage. A total of 78 species which belonged to 2 classes, 14 orders, 41 families and 69 genera, were collected. Sciaenidae, Engraulidae and Gobiidae were the most abundant families each with 7~8 species. 60 species were collected in summer with highest species richness, followed by summer and spring (49 species were collected both of those two seasons). There were more warm water species collected in the studied area (41 species) than warm temperature species (37 species). There were much more ground fish than near-ground and pelagic fish in spring while near-ground fishes became dominant eco-types in summer and autumn. As to composition and variation of dominant species, Miichthys miiuy was among the most abundant fishes for all of the seasons. Larimichthys polyactis became dominant species in spring and summer. Collichthys lucidus dominated fish community in summer and autumn. Coilia mystus, Thryssa kammalensis and Pampus argenteus became dominant species only for one season. The average dissimilarity between each of the two seasons is 0.467 ± 0.025. Fish assemblages in Jiangsu near-shore areas shifted significantly not only spatially but also all temporally. Although fish assemblage patterns were much more complicated in spring than summer and autumn, 4 regional fish assemblage patterns, namely North Jiangsu fish community, Haizhou bay fish community, Middle-south Jiangsu fish community and North Jiangsu fish community can be differentiated basically.