泾河宁夏段夏季浮游生物群落结构特征

2010年7-8月对泾河宁夏段浮游生物群落组成进行了调查。结果表明,该河段浮游植物种类有6门、81种（属）,密度为1.1万～11.6万个/L,平均密度为4.37万个/L。生物量为0.024～0.210mg/L,平均生物量为0.083mg/L。浮游动物有4门、54种（属）,密度为60～185个/L,平均密度为107.73个/L。生物量为0.02～0.66mg/L,平均生物量为0.24mg/L。浮游植物多样性指数表明,该河段水质良好,浮游生物群落结构不稳定,易受外界的干扰。

Community Structure of Plankton of the Jing River in Ningxia in Summer

The compositions of plankton community in the Jing River of Ningxia section were investigated from July to August in 2010.The results showed that： 81 species （genera）, falling into 6 phyla of phytoplankton were observed in the river reach, with density of phytoplankton 1.1 × 104 -11.6 × 104 cells/L, average density 4.37 × 104 cells/L, range of biomass 0.024-0.210 mg/L, and average biomass 0.083 mg/L. Meanwhile, 54 species （genera）, in 4 phyla of zooplankton were observed, with density 60-185 ind/L, average density 107.73 ind/L, range of Biomass 0.02-0.66 mg/L, and average biomass 0.24 mg/L. The richness index of plankton in the Jing River showed that water quality of the river reach surveyed was in good condition; plankton community was of structural instability, and hence was vulnerable to environmental changes.