衡水湖浮游植物多样性分析及评价

Analysis and Evaluation of Phytoplankton Diversity in Hengshui Lake

对衡水湖2016年5—10月的浮游植物多样性进行了监测分析,结果表明衡水湖水体中共有浮游植物6门57种,物种较丰富。浮游植物群落组成以绿藻门、硅藻门和蓝藻门为主,合计占总种类数的87. 72%。与其他研究者的调查成果进行对比分析,在时间上呈现出先下降后上升的趋势,可能与人类活动干扰和调水有关。浮游植物细胞密度月平均值为42. 86×106个/L,3个样点的细胞密度处于5. 84×106~125. 74×106个/L之间,各样点各月之间变化幅度较大。蓝藻门占优势,细胞密度最大,为106. 12×106个/L,基于细胞密度评价衡水湖营养状况,中营养和中富营养占比大,水体富营养化程度较高。利用Shannon-Wiener和Margalef指数计算衡水湖浮游植物多样性指数范围分别为1. 22~3. 36和0. 85~1. 85,综合评价其水质为中度污染。

The phytoplankton diversity of Hengshui Lake was analyzed from January to October in 2016. The results showed that there were a total of 57 species and 6 phyla in Hengshui Lake. The phytoplankton community was mainly composed with Chlorophyta, Bacillariophyta and Cynophyta, accounting for 87.72% of the total species. Compared with the findings of other researchers, it showed a trend of first decline and then rise in time, which might be related to the disturbance of human activities and water transfer. The monthly average cell density of phytoplankton was 128.58 × 10 6 / L, and the cell density of the three samples were 5.84× 10 6 / L ～125.74 × 10 6 / L. Cynophyta was dominant and had the maximum cell density of 106.12×10 6 / L. The autrophication level of Hengshui Lake was high, most of results were mesotropher and middle eutropher. This paper used the Shannon-Wiener index and the Margalef index to calculate the phytoplankton diversity index of Hengshui Lake, which ranged from 1.22 to 3.36 and from 0.85 to 1.85,respectively, and the water quality assessment was moderate pollution.