北京牛口峪水库水生生物多样性及环境评价

Aquatic Biodiversity and Environmental Assessment in Niukouyu Reservoir, Beijing

摘要: 在2017年和2018年夏秋季，以及2021年夏季，对北京牛口峪水库开展了5次水质状况和浮游生物群落采样调查，旨在为保护水库水生生物多样性和控制水域污染提供科学依据。结果表明，水库氮磷处于较高水平，总氮除2018年夏季为III类标准，其余皆为V类标准及以上；总磷平均为III类标准。加权综合营养指数显示水质总体为轻度富营养状态，污染程度处于轻度污染。浮游植物平均密度为5.35 × 106 ind./L，平均生物量为7.85 mg/L，平均多样性指数为3.60；平均均匀度指数为0.53，以硅藻门和绿藻门为优势，存在潜在的水华暴发风险。浮游动物平均密度为9430 ind/L，生物量平均值为2.61 mg/L，以原生动物和轮虫为优势，平均多样性指数为3.42，平均均匀度指数为0.64，存在小型化的趋势，浮游生物的多样性指数和均匀度指数有所降低。建议加强水质监测和管理，控制氮磷输入，保护生物的多样性和稳定性，实现水资源的可持续利用。

Abstract: Five sampling investigations were conducted on the water quality and plankton community characteris-tics in Beijing Niukouyu Reservoir at the summer and autumn of 2017 and 2018, as well as in the summer of 2021, aiming to provide scientific basis for the protection of aquatic biodiversity and the control of wa-ter pollution. The results showed that the nitrogen and phosphorus levels were at a high level. The total nitrogen was classified as Class V or above except in the summer of 2018, and the average total phospho-rus was Class III. The weighted comprehensive nutrition index showed that the water quality was gener-ally mildly eutrophic, and the pollution degree was mild. The average density of phytoplankton was 5.35 × 106 ind./L, the average biomass was 7.85 mg/L, and the average diversity index was 3.60. The average evenness index was 0.53, with Diatoms and Chlorophyta as the dominant species, and there was a poten-tial risk of algal blooms. The average density of zooplankton was 9430 ind/L, the average biomass was 2.61 mg/L, with protozoa and rotifers as the dominant species, and the average diversity index was 3.42. The average evenness index was 0.64, with a smaller trend, and the diversity index and evenness index of zooplankton decreased. It is suggested to strengthen water quality monitoring and management, control nitrogen and phosphorus input, protect biodiversity and stability, and achieve sustainable use of water resources.