京津冀重要水源地潘大水库水生生物群落结构及水质生物学评价

The aquatic organism communities of the Panjiakou-Daheiting Reservoir and the bioassessment of water quality

潘家口和大黑汀水库(合称"潘大水库")是京津冀区域重要的饮用水源地,其水生态系统状况可以直接反映受水区域的供水安全。本研究通过浮游植物、浮游动物和大型底栖动物的野外生态监测,基于水生生物群落结构分析了潘大水库水生态系统现状并进行了生物学评价。结果表明:潘大水库浮游植物种类以硅藻和绿藻占优势,密度以金藻和蓝藻占优势,浮游植物密度最高密度达14.45×107ind·L^(-1),呈现水华状态,主要由金藻贡献;浮游动物主要由轮虫、枝角类和桡足类组成,空间差异较小,种类以轮虫占优势,密度上则以桡足类占优势;浮游动物Shannon多样性指数(H)较高,为2.31~2.50;底栖动物种类以摇蚊科和颤蚓科为主,密度上表现出明显的空间差异,最高密度达14400 ind·m^(-2),主要由指示有机污染的颤蚓科贡献,底栖动物多样性较低,除最上游的H为0.92外,其余均低于0.40。基于浮游植物和底栖动物进行的生物学评价结果表明,潘大水库部分区域的污染状态较重。

Panjiakou and Daheiting reservoirs （known as Pan-Da Reservoir） serve as the important drinking water source for the Beijing-Tianjin-Hebei area. The status of the reservoir ecosystem is an important indicator to water supply security. Based on field investigations of phytoplankton, zooplankton and macroinvertebrates, we analyzed the community composition and evaluated the status of the aquatic ecosystem and water environment. The results showed that phytoplankton community was dominated by Bacillariophyta and Chlorophyta, while the density was mainly con- tributed by Chrysophyta and Cyanophyta. The maximum density of phytoplankton in the reservoir was up to 14.45x 107 ind · L-1, showing a algal-bloom status. Zooplankton community was mainly composed of Rotifer, Cladocera and Copepoda, and their spatial difference was not identified. Rotifer dominated the community, while Cladocera dominated the density. The Shannon diversity index （H） of zooplankton ranged from 2.31 to 2.50. Macroinvertebrate community was dominated by Chironomidae and Tubificidae. Their densities showed significant difference in spatial distribution; the highest value was up to 14400 ind · m-2, mainly contributed by Tubificidae indicating severe organic pollution. H of macroinvertebrates of all sites was lower than 0.40, except a value of 0.92 for one site in the most upper reach. Bioassessment of phytoplankton and macroinvertebrates indicated that the reservoir suffered serious pollution in the study period.