吉林水利

本文采用野外生态学方法,于2016—2018年6月和9月对北京密云水库浮游植物多样性及水生态环境进行了研究。结果表明,密云水库浮游植物共检出8门56属108种,浮游植物平均密度为3.66×106ind./L,平均生物量为7.90mg/L,优势种为尖脆杆藻(Fragilaria acus),种类组成、密度和生物量均以绿藻和硅藻为主,蓝藻占比适中,但种类和密度仍较多。蓝藻存在显示有富营养化和水华爆发的可能。除氮磷指标外,其余理化指标均处在国家标准Ⅰ-Ⅱ类,氮磷仍是潜在富营养化因素。总之,南水北调后,密云水库浮游植物群落结构复杂,浮游植物在种类组成和数量上变化明显,多样性和均匀性均较好,但仍预示着潜在的水华和富营养化风险。水质多为中营养状态,水质状况总体良好,但仍存在氮磷含量高和富营养化等问题,水库控制氮磷负荷仍不容忽视。

In this paper,the authors carried out the study on phytoplankton diversity and water ecological environment for Miyun reservoir in Beijing from the year 2016 to 2018 by means of field ecological method.The results show that there are 8 categories,56 spcies,and 108 kinds of phytoplankton being discovered in Miyun reservoir,its average density is about 3.66*106 ind./L,the average biomass is 7.90 mg/L,the dominant species is Fragilaria acus,and the species composition,density and biomass are all mainly green alga and diatom,the proportion of blue-green algae is moderate,while its species and density are still more.Blue-green algae exist shows that it is possible for the eutrophication and the algal bloom break out.Apart from nitrogen and phosphorus indexes,other physical and chemical ones are all satisfied with the national standards Ⅰ-Ⅱ,and nitrogen and phosphorus are still potential factors resulting in the eutrophication.In a word,after implementation of of South to North Water Diversion Project,the structure of phytoplankton coenosium is complicated in Miyun reservoir,the variation of phytoplankton in species and quantities is obvious,and both its diversity and uniformity are better,but there are still potential risk that the eutrophication and the algal bloom break out.Most of water quality in the reservoir are the mesotrophic state,the water quality situation as a whole is good,while there are still the problems about high contents of nitrogen and phosphorus in the water and the eutrophication.The work to control contents of nitrogen and phosphorus can not be still ignored for managers of the reservoir.