三江平原沼泽湿地底栖无脊椎动物群落特征

为探明现阶段三江平原沼泽湿地底栖无脊椎动物群落结构及物种多样性，于2017年春、夏、秋3个季节对6个样点开展了调查.共记录3门41科72种，以水生昆虫和腹足纲为主.平均密度为（139.68±29.13）ind./m²，季节上，底栖无脊椎动物密度表现为秋季>春季>夏季.三江平原沼泽湿地主要优势种具有一定的季节性变化，其中，西伯利亚盘螺Valvata sibirica为3个季节共有优势种.指示物种分析表明：春季指示种为Potamonectes sp.，夏季指示种为Lethocerus sp.、Gyraulus centrifugus、Erpobdellidae sp.；秋季指示种为Sgementina nitida.整体上，春季Shannon-Wiener多样性指数（H'）、均匀度指数（J）、Margalef丰富度指数（d_M）均比夏、秋季高.单因素方差分析表明，Shannon-Wiener多样性指数（F=1.480，p=0.259）、Margalef丰富度指数（F=0.056，p=0.946）、Pielou均匀性指数（F=2.038，p=0.165）均不存在季节性差异.

Community characteristics of benthic invertebrate in marsh wetlands of the Sanjiang Plain,China

To explore the characteristics of community structure and species diversity of benthic invertebrates, three samplings of 6sites in marsh wetlands of the Sanjiang Plain were conducted in May, July and September, 2017. In total, 72 taxa of benthic invertebrates from 41families and 3phyla were recorded, mainly composed by aquatic insects and gastropoda. The average density of benthic invertebrates was (139.68±29.13)ind./m². Seasonally, the density of benthic invertebrates followed the order of autumn > spring > summer. The dominant species varied in different seasons, with the Valvata sibirica being the dominant species in three seasons. Indicator species analysis showed that Potamonectes sp. was the indicator species in spring, Lethocerus sp., Gyraulus centrifugus and Erpobdellidae sp. were the indicator species in summer, and Sgementina nitida was the indicator species in autumn. On the whole, Shannon-Wiener diversity index (H'), Pielou evenness index (J), and Margalef richness index (d_M) were all higher in spring than in summer and autumn. One-way ANOVA analysis showed that there were no significant differences in Shannon-Wiener diversity index (F=1.480, p=0.259), Margalef richness index (F=0.056, p=0.946), and Pielou evenness index (F=2.038, p=0.165) among the three seasons.