秦山岛海域大型底栖动物群落结构的季节变化

于2015—2016年在秦山岛海域开展4个航次的大型底栖动物调查，用优势度指数法和多样性指数法对底栖动物优势种和多样性状况进行评价。结果显示，四季共采集鉴定底栖动物7门69种，其中环节动物25种，软体动物19种，节肢动物16种，棘皮动物3种，脊索动物、纽形动物和腔肠动物各2种；优势种共14种。大型底栖动物种数和密度均值均为春季＞秋季＞夏季＞冬季，生物量均值为夏季＞冬季＞春季＞秋季，密度和生物量的空间分布无明显规律。多样性评价结果表明，秦山岛海域底栖动物群落受到轻度干扰，底栖环境处于轻度污染状态；除人为干扰和环境因子外，种间关系及生活史特征也是影响底栖动物群落结构变化的重要因素。

Seasonal Variation of Macrobenthos Community Structure in Qinshan Island Sea Area

4 investigations were carried out on macrobenthos in Qinshan Island sea area from 2015 to 2016, and the dominant species and diversity of macrobenthos were evaluated using dominance index and diversity index. The results showed that 69 species of macrobenthos in 7 phyla were collected and identified in four seasons, including 25 species of annelids, 19 species of mollusks, 16 species of arthropods, 3 species of echinoderms, and 2 species of chordates, nemertea and coelenterates each. There were 14 dominant species. The number of species and mean density of macrobenthos in descending order were in spring, autumn, summer, winter, and the mean biomass in descending order was in summer, winter, spring, autumn. There was no obvious rule in the spatial distribution of density and biomass. The results of diversity evaluation showed that macrobenthos community was slightly disturbed and the benthic environment was slightly polluted. In addition to human interference and environmental factors, interspecific relationships and life history characteristics were also the important factors affecting the changes in macrobenthos community structure.