滆湖底栖动物群落的时空变化及水质生物学评价

2009年5月-2010年2月对滆湖底栖动物群落进行了调查,并根据底栖动物群落结构对水质进行了生物学评价。结果表明:采集到底栖动物共35种,隶属于3门25属;优势种类为中国长足摇蚊(Tanypus chinensis)、霍甫水丝蚓(Limnodrilus hoffmeisteri)、苏氏尾鳃蚓(Branchiura sowerbyi)、克拉泊水丝蚓(L.claparedeianus)、中华河蚓(Rhyacodrilussinicus);滆湖底栖动物的年均密度为374.1ind·m-2,寡毛类对密度的贡献最大,占年均密度的77.4%,最大密度出现在夏季,春季最低,St14年均密度高于其他站点;滆湖底栖动物的年均生物量为17.78g·m-2,软体动物对生物量的贡献最大,占年均生物量的97.4%,夏季生物量最大,冬季最低,St14年均生物量明显高于其他各个站点;底栖动物的密度和生物量随季节变化明显,密度的季节变化表现为夏季>秋季>春季>冬季,生物量变化表现为夏季>春季>秋季>冬季;Shannon-Wiener多样性指数值(H’)、Margalef多样性指数值(D)、Pielou均匀度指数值(J)和BI指数值表明滆湖水体处于中度到重度污染状态。

Spatiotemporal variation of zoobenthos community and bio-assessment of water quality in Gehu Lake

From May 2009 to February 2010, an investigation was conducted on the zoobenthos community in Gehu Lake, and the water quality of the Lake was assessed based on the structure of the zoobenthos community. A total of 35 zoobenthos species belonging to 3 phyla and 25 genera were identified, among which, Tanypus chinensis, Limnodrilus hoffmeisteri, Branchiura sowerbyi, L. claparedeianus, and Rhyacodrilus sinicus were dominated. The annual density of the zoobenthos averaged 374.1 ind·m-2, and oligochaeta contributed most, occupying 77.4% of the total. The annual biomass averaged 17.78 g·m-2, and molluscs had the most contribution (97.4%). The density and biomass of the zoobenthos were the highest in summer, but the lowest in spring and in winter, respectively. Among the observation stations, St14 had relatively higher zoobenthos density and biomass. The zoobenthos density and biomass varied greatly with season. The highest density occurred in summer, followed by in autumn, spring, and winter; the highest biomass occurred in summer, followed by in spring, winter, and autumn. The values of Shannon-Wiener diversity index, Margalef species richness index, Pielou index, and BI index suggested that the Gehu Lake was of moderate to serious pollution.