日照市近海大型底栖动物群落结构和生物多样性

于2018年7(夏季)、10(秋季)、12月(冬季)和2019年4月(春季)在日照近海18个站位进行了大型底栖动物调查。共鉴定出大型底栖动物7门72科119种,其中:多毛类动物28科62种,为优势类群;甲壳动物26科36种、软体动物11科12种、棘皮动物3科4种和其他类群5种。主要优势种为寡鳃齿吻沙蚕(Micronephthys oligobranchia)、不倒翁虫(Sternaspis scutata)、中蚓虫一种(Mediomastus sp.)、圆筒原盒螺(Cylichna biplicata)和海稚虫科未定种(Spionidae und.)等。调查海域大型底栖动物年平均丰度和生物量分别为191 ind./m;和6.71 g/m;。多样性指数(H′)、均匀度指数(J)和丰富度指数(d)的平均值分别为2.912、0.934和2.139。聚类分析结果显示,4个季度的群落相似性系数均较低,分布格局存在季节性变化。ABC曲线分析表明,4月大型底栖动物群落可能存在轻微污染或扰动。对比分析历史研究数据发现,伴随海岸带开发及人类活动的持续影响,日照近海的大型底栖动物优势种变化明显,耐污种奇异稚齿虫(Paraprionospio pinnata)逐渐成为优势种,丰度、生物量和Shannon-Wiener多样性指数则呈现下降趋势。

Community structure and biodiversity of macrobenthos in the coastal waters of Rizhao

Spatial-temporal distribution of macrobenthic community was studied in the coastal waters of Rizhao in July, October, December 2018 and April 2019. A total of 119 macrobenthic species were identified during the surveys, including 62 species of polychaetes, 36 species of crustaceans, 12 species of molluscs, 4 species of echinoderms and 5 species of other groups. According to the Index of Relative Importance, the community was dominated by Micronephthys oligobranchia, Sternaspis scutata, Mediomastus sp., Cylichna biplicata, and Spionidae und.. Abundance and biomass varied seasonally with the mean abundance of 191 ind./m² and mean biomass of 6.71 g/m². Values of average Shannon-Wiener species diversity index (H''), Pielou''s evenness index (J), and Margalef''s richness index (d) were 2.912, 0.934 and 2.139, respectively. The CLUSTER results based on Bray-Curtis similarity indicated that the similarity among macrobenthic community groups was low and the distribution pattern of macrobenthic community showed seasonal characteristics. According to the Abundance-Biomass comparison curve (ABC), community from one season (April, 2019) was slightly disturbed.With the rapid development of coastal zones and the continuous impacts of human activities, the dominant species of macrobenthic community changed obviously, showing a decreasing trend of abundance, biomass and H'', and the contamination tolerant species Paraprionospio pinnata had gradually became the dominant species.