青草沙水库后生浮游动物群落结构及其与环境因子的关系

Community structure of metazoan zooplankton and its relationships with environmental factors in Qingcaosha Reservoir of Shanghai, East China

于2011年1月、4—12月对青草沙水库后生浮游动物(轮虫、枝角类和桡足类)的群落结构、时空分布进行了调查,并对其与环境因子的相关性进行了分析。结果表明:观察到青草沙水库后生浮游动物62种,其中轮虫38种,枝角类11种,桡足类13种;后生浮游动物密度年均值为469.1ind·L-1,生物量年均值为3.23mg·L-1。从青草沙水库后生浮游动物优势种类组成以及QB/T值(为1)分析,库区水质处中营养型。根据轮虫的Shannon及Margalef多样性指数,库区水质属β-中污型。GAM和CCA分析均表明,水温对轮虫密度影响较大,是造成轮虫种类分布差异的主要因子;GAM分析也显示了枝角类密度和透明度、溶氧存在较好的非线性关系。

An investigation was conducted on the spatiotemporal distribution of metazoan zoo- plankton （including Rotifers, Cladocera, and Copepoda） in the Qingcaosha Reservoir of Shang- hai in January and April-December, 2011, with the relationships between the distribution pattern of the metazoan zooplankton and environmental factors analyzed. A total of 62 metazoan zooplank- ton species were observed, consisting of 38 Rotifers, 11 Cladocera, and 13 Copepoda. The year- ly density of the zooplankton was averagely 469. 1 ind ·L-1, and the biomass averaged 3.23 mg · L-1. Based on the dominant species composition of metazoan zooplankton and the QB/T value of Rotifers biological index （ QB/T = 1 ）, the water quality of the Reservoir was at mesotrophie state. According to the Shannon and Margalef biodiversity indices of Rotifers, the water quality of the Reservoir was of β-pollution pattern. Both the GAM and the CCA analyses showed that water temperature had considerable effects on the Rotifers density, being the key factor affecting the distribution discrepancies of the Rotifers. The GAM analysis also showed that the Cladocera den- sity had non-linear relationships with the water transparency and dissolved oxygen.