突发环境污染事件对湖泊浮游动物的影响

Study on Effects of the Environmental Pollution Incident on the Zooplankton

中国北方某地空难对某湖泊浮游动物的种类、群落结构、优势种和个体密度及其空间分布产生了重要影响.基于浮游动物的水质生物学评价显示:①该湖泊有浮游动物24种,其中原生动物9种,优势种为累枝虫;轮虫7种,优势种为萼花臂尾轮虫;枝角类4种,优势种为直额裸腹;桡足类4种,优势种为直刺北镖水蚤;浮游动物优势种多为α-中污带或β-中污带的指示种类和富营养化指示种类.②浮游动物个体密度(4 770 L-1)较小且分布不均匀,空难事故发生地及其附近区域的种类数和个体密度均为最低值,桡足类在其中4个样点没有出现.③浮游动物的Shannon-Wiener多样性指数略高于1,结合浮游动物个体密度、群落结构、优势门类和种类,可以认为该湖泊水体污染和富营养化程度比较严重,这一结果与该湖泊水质理化评价结果(1.030 5)基本一致.

One Air Disaster occurred in North China has had important influence on the species, community composition, dominant species, individual density and spatial distribution in the attached lake. The bio-assessment of zooplankton shows： ① There are 24 species of zooplankton in the lake, including 9 species of protozoa, with Epistylis sp. as dominant species ; 7 species of Rotifera, with Brachionus calyciflorus as dominant species; 4 species of cladoceran, with Moina rectirostris as dominant species; and 4 species of copepoda, with Arctodiaptomus rectispinosus as dominant species. The dominant species are mostly indicators of polluted and eutrophic water body and amoderately and β-moderately polluted zones. ②The individual density of zooplankton is small （4 770 L^-1 ） and distributes unevenly. The species＇ amount and the individual density are the least in the place where the plane prang. There is no copepoda in 4 sampling stations. ③ The Shannon-Wiener diversity index was slightly higher than 1 in the lake. In combination with the individual density, community composition and dominant species of the zooplankton, it was concluded that file lake was densely polluted and belonged to severe eutrophic water, which is basically consistent with the physiochemical assessment results of lake water quality.