兴隆湖春季和冬季浮游生物群落结构特点及其水质状况指示意义

Plankton Community Structure and Water Quality Indexes in Spring and Winter in Xinglong Lake

为评价成都天府新区兴隆湖浮游生物现状及其水质状况指示意义,并积累成都地区浮游生物基础资料。于2015年1月(冬季)和4月(春季)对兴隆湖浮游生物和水质进行了采样调查和分析。共检出浮游植物5门43属53种,其中优势种以绿藻门、裸藻门和蓝藻门的藻类为主,共检出浮游动物23属33种,其中优势种以原生动物、轮虫和无节幼体为主。兴隆湖春季浮游生物现存量大于冬季,其中浮游植物平均现存量分别为1.99×10~6cells/L和6.15×10~5cells/L,浮游动物平均现存量分别为4 243ind./L和631ind./L。春季和冬季浮游生物Shannon-Wiener多样性指数(H')均值分别为1.83和1.61,丰富度指数(Dm)均值分别为2.60和1.88,均匀度指数(J)均值都为0.64,表明两个季节兴隆湖均处于中度污染状态,但春季略优于冬季;水体理化指标监测结果表明,兴隆湖水质属劣Ⅴ类,主要污染物为氨氮、总氮和总磷,春季污染物浓度较冬季有所下降。比较各样点浮游生物与水体理化指标的水质评价结果可知,对于类似兴隆湖的范围较小的水体,各样点浮游生物指数评价结果与水质指标评价结果并不完全一致,浮游生物指数适宜进行整体的水质状况评价,水质指标则适用于评价湖泊各个点的水质状况。

To study the current status of plankton community and the significance of water quality indexes in xinglong lake of Tianfu New District,and accumulate the basic data of plankton community in Chengdu,the plankton community structure and the water quality in Xinglong lake were investigated and analyzed in January and April,2015. A total of 53 phytoplankton and 33 zooplankton species were identified,which belonged to 43 and 23 genera,respectively. The dominant species of phytoplankton in Xinglong lake were species of Chlorophyta,Euglenophyta and Cyanobacteria,while the dominant species of zooplankton were species of Rotifers,Protozoa and Nauplii. The existing quantity of plankton in spring is greater than in that in winter,the existing quantityof phytoplankton in spring and winter were 1. 99 × 10^6 cells/L and 6. 15 × 10^5 cells/L,respectively,while the existing quantity of zooplankton in spring and winter were 4 243 ind./L and 631 ind./L,respectively. The mean values of the diversity indices（ H′） of xinglong lake in spring and winter were 1. 83 and 1. 61,respectively,the mean values of the abundance（ Dm）of xinglong lake in spring and winter were 2. 60 and 1. 88,the mean values of the evenness indexes（ J） of xinglong lake in spring and winter were both 0. 64,which indicated that the water quality of xinglong lake was moderate pollution,and spring was better than winter. The monitoring results of water physical and chemical indexes indicated that the water quality of xinglong lake was worse than the V class. NH3-N,TN and TP were the major pollutants in xinglong lake,their concentration were less in spring than in winter. For small lakes like xinglong lake,the evaluation results of plankton indexes was not exactly the same as the evaluation results of the water physical-chemical indexes. The plankton index is appropriate for the assessment of the whole lakewater quality,the water physical and chemical index is appropriate for the water quality assessment of each sampling site.