围网拆除后升金湖后生浮游动物群落结构及环境影响因子

研究围网拆除后升金湖后生浮游动物群落结构及其与环境因子间的关系,为今后升金湖生态恢复及生物多样性保护提供科学依据。2018年4月至2019年1月对升金湖区域后生浮游动物及环境因子进行了调查。调查结果显示,后生浮游动物优势种共9种,密度和生物量平均值分别为(356±52.1)个/L(、30.2±4.68)mg/L。Shannon-Wiener多样性指数、Margalef丰富度指数和Pielou均匀度指数平均值分别为:2.54(1.953.15)、1.92(0.872.34)、0.73(0.550.85)。Pearson相关性分析与RDA分析结果表明,影响升金湖后生浮游动物群落结构的主要环境因子为电导率、TP浓度、NH4+-N浓度、水生植被盖度、水温、Chl-a浓度等。围网拆除后水体的透明度、浊度、溶解氧浓度均有改善,但营养盐浓度并未发生显著变化,与2016年前的升金湖调查数据相比,后生浮游动物密度和生物量均有所增加,种类由中污型向寡污型转化趋势明显。

Metazoan Zooplankton Community Structure and Influencing Factors in Shengjin Lake After Purse Seine Removal

In order to study the relationship between the metazoan metazoan zooplankton community structure and its influencing factors in the Shengjin Lake after the seine had been completely removed, we investagated the metazoan zooplankton community structure and its influencing factors in the Shengjin Lake area from April 2018 to January 2019. The survey results showed there were 9 dominant species recorded,, The average density and biomass of metazon metazoan zooplankton were 356 ± 52.1 ind./L and 30.2 ± 4.68 mg / L, respectively. The average values of Shannon-Wiener diversity index, Margalef richness index, and Pielou uniformity index were: H` was 2.54 (1.95~3.15), D was 1.92 (0.87~2.34), and J was 0.73 (0.55~0.85).Pearson correlation analysis and RDA analysis results showed that the main environmental factors affecting the community structure of metazoan zooplankton in Shengjin Lake were electrical conductivity, TP concentration, NH4+-N concentration, macrophyte coverage, water temperature, and Chl.a concentration. Compared with the survey data of Shengjin Lake before 2018, the data of this survey had significantly increased the density, biomass and diversity index of metazoan metazoan zooplankton, indicating that the removal of the purse seine had a good effect on the improvement of the community structure of metazon metazoan zooplankton in Shengjin Lake. After the removal of the purse seine, the function of the aquatic ecosystem in Shengjin Lake is gradually recovering.