杭州湾大型底栖动物季节分布及环境相关性分析

Seasonal distribution of macrozoobenthos in relation to environmental factors in Hangzhou Bay

对杭州湾大型底栖动物进行了夏(2006年7-8月)、冬(2006年12月-2007年1月)、春(2007年4月)、秋(2007年10-11月)季调查,分析了大型底栖动物的季节分布及其与环境的关系。结果表明:本海域四季共鉴定出113种大型底栖动物,多毛类、软体动物和甲壳类是该海域大型底栖动物的主要类群;主要优势种为双鳃内卷齿蚕、西方似蛰虫和多鳃卷吻沙蚕等多毛类。方差分析表明,除甲壳类丰度外,杭州湾大型底栖动物群落参数无显著季节差异,群落分析表明,杭州湾群落特点比较单一,未分辨出显著差异的群落;丰度/生物量比较法分析表明,秋季杭州湾海域受到了污染的扰动;典范对应分析表明,多毛类主要受物理因子(如温度、盐度、水深等)影响,而软体动物、甲壳类和其他类动物主要受生物化学因子(如叶绿素、总有机碳、浮游生物等)影响。从典范对应分析的结果,可以推断出杭州湾大型底栖动物受自然环境特征的影响较人类活动的影响大。

To evaluate the seasonal distribution of macrozoobenthos and its relationship with environmental factors in the Hangzhou Bay, four cruise surveys were carried out in summer, winter, spring and autumn during 2006--2007. A total of 113 species were identified with the dominant groups of polychaetes, mol- lusks and crustaceas. Aglaophamus dibranchis, Amaeana occidentalis and Nephtys polybranchia were the dominant species in this area. Based on the results of analysis of variance, no significant seasonal differ- ences were found in community parameters except for the crustacea density. Both the Bray-Curtis similari- ty analysis and non-metric multidimensional scaling analysis showed no obvious differences of community composition were observed in the Bay. Indicating a relatively simple macrobenthic community feature. The abundance/biomass curves showed that macrobenthic communities were disturbed in autumn. The canoni- cal correspondence analysis showed that the polychate was mainly affected by the physical variables, while mollusk, crustacea and other taxa were mostly influenced by the biological and chemical parameters were the main factors influencing. The result of CCA also could inferred that the macrobenthos in the Hangzhou Bay were primarily influenced by the natural environment features, rather than the human activities.