浙江舟山海域大型底栖动物群落组成及主要影响因子分析

为了解舟山附近海域大型底栖动物群落组成特点及其与环境因子的内在关联,在2019~2020年对舟山附近海域12个站位的大型底栖动物及环境因子进行了调查研究。采用丰度、生物量、相对重要性指数(IRI)、Cluster聚类以及PCoA分析和Pearson相关性分析等方法对该海域的大型底栖动物群落组成、主要影响环境因子进行了分析。结果表明,两个航次共在舟山海域采集到大型底栖动物56种,其中多毛类动物28种,甲壳动物8种,软体动物7种,棘皮动物6种,刺胞动物3种、纽形动物2种,星虫动物和脊索动物各1种;两年平均丰度和生物量分别为36.32ind./m²和5.59g/m²,纽虫(Nemertea)是丰度的最大贡献者,而星虫爱氏海葵(Edwardsia sipunculoides)和棘刺锚参(Protankyra bidentata)则是生物量的最大贡献者;2020年大型底栖动物的总物种数、丰富度指数和多样性指数高于2019年,且两年舟山海域大型底栖动物的总物种数、丰富度指数和多样性指数均高于舟山邻近海域。与舟山海域大型底栖动物群落最相关的环境因子是水深、底层水盐度和硝态氮(NO₃),这三个环境因子彼此相关性显著,随着盐度的增加,水深逐渐增加而硝酸氮含量则显著降低,群落物种数、丰度和丰富度则显著增加。通过对舟山附近海域大型底栖动物群落组成特点及其与环境因子的内在关联的研究,有望为东海近岸海域大型底栖动物群落的演替规律研究提供基础数据和科学依据。

COMPOSITION AND MAIN ENVIRONMENTAL FACTORS OF MACROBENTHOS COMMUNITY IN SEA AREA OF ZHOUSHAN ISLANDS, ZHEJIANG

To understand the characteristics of macrobenthic community composition and its internal correlation with environmental factors, a survey was conducted at 12 stations in the sea areas of Zhoushan Islands in 2019~2020. The composition and structure of macrobenthic community were scrutinized by means of abundance, biomass, index of relative importance (IRI), cluster clustering, PCoA analysis, and Pearson correlation analysis. The main environmental factors affecting the macrobenthic community in this sea area were analyzed. The results showed that a total of 56 species of macrobenthos were collected in the waters of Zhoushan during the two voyages, including 28 polychaetes, 8 crustaceans, 7 mollusks, 6 echinoderms, 3 cnidarians, 2 nemertea species, 1 species each of sipuncula and chordata. The two-year average abundance and biomass were 36.32 ind./m² and 5.59 g/m², respectively. Nemertea was the largest contributor to the abundance, while Edwardsia sipunculoides and Protankyra bidentata were the largest contributors to biomass. The total number of species, richness index, and diversity index of macrobenthos in 2020 were higher than those in 2019, and they were greater in the waters of Zhoushan Islands in the two years than those in the adjacent sea area. The most important environmental factors were water depth, bottom water salinity, and nitrate nitrogen (NO₃). These three environmental factors were significantly correlated with each other. With the increase of salinity, the water depth increased gradually, while the nitrate content decreased significantly, and the species number, abundance, and richness of the community increased significantly. This study provided basic data and scientific basis for the understanding of the succession of macrobenthic community in the coastal waters of the East China Sea.