象山港中部海域大型底栖动物群落组成及多样性特征

2012年4月、7月、9月和12月对象山港海域11个大面站进行了大型底栖动物调查研究,采用优势度(Y)、ShannonWeaver多样性指数(H')、Margalef丰度指数(d)、Pielou均匀度指数(J')分析该海域大型底栖动物优势种、物种多样性及群落种类组成,用Bray-Curtis相似性系数聚类分析和多维排序尺度(MDS)分析大型底栖生物群落结构,以及采用丰度/生物量比较曲线(ABC曲线)法分析大型底栖动物群落受污染扰动的状况。调查结果显示软体动物中的半褶织纹螺(Nassarius semiplicatus)成为最主要的优势种,4季均可成为优势群体;Shannon-Weaver多样性指数平面分布与Margalef丰度指数平面分布大体一致,Pielou均匀度指数的空间变化相较于Margalef丰度指数与ShannonWeaver多样性指数变化不大,说明每站种类组成的差异较小,站间分布均匀;大型底栖动物群落4季主要分布为靠近调查海域北岸和中部的站位相似性较高和靠近调查海域南岸的站位相似性较高,海域环境的不同形成不同的生境,进而在群落结构分布上形成不同的类群;ABC曲线分析表明,4月、7月大型底栖动物群落未受到污染扰动,9月、12月受到了轻微的污染或者扰动,主要影响因素与温排水、工业三废的排放、自然岸线和湿地面积的减少有关。

Community structure and biodiversity characteristics of macrobenthos in the middle of Xiangshan Bay

In April, July, September and December, 2012, the investigations of macrobenthos in the Xiangshan Bay were carried out, and the macrobenthic dominant species, species diversity and community species composition were analyzed using the dominant species index (Y), Shannon-Weaver diversity index (H'), Margalef richness index (d) and Pielou evenness index (J'). We adopted the Bray-Curtis similarity matrix and MDS analysis of Xiangshan Bay macrobenthos community structure, pollution disturbance conditions analyzed by the ABC Curve method. The investigation showed that Nassarius semiplicatus became the dominant species and were four seasons dominant groups. Shannon-Weaver diversity index was broadly consistent with the distribution of Margalef abundance index horizontal distribution, and Pielou index changed compared to the Margalef richness and Shannon-Weaver diversity index changed little, indicating the various kinds of individuals in the community had little differences, evenly distributed between stations. Macrobenthic community was distributed mainly in the investigation area near the north coastal and central had higher similarities, and near the south coastal stations similarity wiht the same, marine environment different with the habitats formed, and then distributed in the community structure formed of two different groups. The results of ABC Curve method indicated that in April, July macrobenthic community was not polluted and September and December had slight polluted disturbance. The main factors were connected with thermal discharge, industrial waste emissions, natural coastline and reduced wetlands aera.