贵州高原水库浮游生物群落稳定性及其环境驱动因子辨识

Plankton Community Stability and Drive Factor Identification Guizhou Plateau Reservoir

为了解贵州高原水库环境下,浮游动物及浮游植物群落稳定性情况,水库水质变化影响浮游生物稳定性的过程.于2020年10月和2021年的4、6、8月对3座不同营养型水库(花溪水库、构皮滩水库和海龙水库)的浮游生物群落变化及水质变化进行研究,结合时滞分析(TLA)研究浮游动物和浮游植物群落稳定性,使用方差分解分析(VPA)探究两个群落对环境变化的响应,揭示水库浮游生物群落变化的驱动因子.结果表明,3座水库的综合营养指数(TLI)均值为44.07、44.68和50.25.花溪水库和构皮滩水库为中营养型水库,海龙水库为富营养型水库.总共鉴定出浮游动物轮虫51种,轮虫39种,桡足类3种和枝角类9种.其中轮虫丰度最多,占85.96%.浮游植物鉴定出7门73种,蓝藻门16种,绿藻门32种,硅藻门16种,甲藻门3种,裸藻门4种,隐藻和金藻门各1种.其中蓝藻门和硅藻门丰度占比最大,分别为66.2%和27.35%.浮游动物和浮游植物群落Bray-Curtis距离的绝对偏差中位数(MAD)分别为:花溪水库0.67和0.65、构皮滩水库0.80和0.69、海龙水库0.85和0.47,值越大说明群落的变异越大. TLA结果中浮游动物的斜率绝对值大于浮游植物的绝对值,斜率绝对值分别为0.018和0.004,斜率绝对值越大群落变异速度越快.浮游动物群落相对浮游植物群落稳定性更低,对环境变化的响应更敏感,变异程度更大.水库的富营养状态程度越高,这种现象越明显.VPA显示,花溪水库和海龙水库浮游生物群落变化主要受到水温和富营养化因子影响.构皮滩水库浮游生物群落变化主要受到水温和化学因子的影响.花溪水库的驱动因子为水温、TP、高锰酸盐指数和SD.构皮滩水库驱动因子为水温、NO_(3)^(-)-N和pH.海龙水库的驱动因子为水温和TP.水温和营养盐是影响水库浮游生物群落稳定性的主要原因.

In order to understand the stability of the zooplankton and phytoplankton communities in the Guizhou plateau reservoir environment,the process of reservoir water quality change affecting the stability of plankton was studied.The changes in the plankton community and water quality in three different nutrient reservoirs(Huaxi Reservoir,Goupitan Reservoir,and Hailong Reservoir)were studied from October 2020 to August 2021.The stability of the zooplankton and phytoplankton communities was studied using time-lag analysis(TLA).Variance decomposition analysis(VPA)was used to explore the response of the two communities to environmental changes.The driving factors of plankton community changes in reservoirs were also revealed.The results showed that Huaxi Reservoir and Goupitan Reservoir were mesotrophic reservoirs,and Hailong Reservoir was a eutrophic reservoir.The average comprehensive nutrition indices of the three reservoirs were 44.07,44.68,and 50.25.A total of 51 species of zooplankton rotifers,39 species of rotifers,three species of copepods,and nine species of cladocera were identified.Among them,the abundance of rotifers was the highest,accounting for 85.96%.A total of seven phyla and 73 species of phytoplankton were identified,including 16 species in the phylum Cyanophyta,32 species in the phylum Chlorophyta,16 species in the phylum Diatoma,three species in the phylum Chlorophyta,four species in the phylum Euglenophyta,and one species each in the phyla Cryptophyta and Chrysophyta.Among them,the abundance of cyanobacteria and diatoms was the highest,accounting for 66.2%and 27.35%,respectively.The median absolute deviation(MAD)of the Bray-Curtis distance of zooplankton and phytoplankton community in the three reservoirs were 0.67 and 0.65 in Huaxi Reservoir,0.80 and 0.69 in Goupitan Reservoir,and 0.85 and 0.47 in Hailong Reservoir,respectively.The larger the value,the greater the variation in the community.The absolute value of the slope of zooplankton was greater than that of phytoplankton in the TLA results,and the absolute values of the slopes were 0.018 and 0.004,respectively.The larger the absolute value of the slope,the faster the community variability.The zooplankton community in the three reservoirs was less stable than the phytoplankton community and more sensitive to environmental changes,and the degree of variation was greater.The higher the degree of eutrophication of the reservoir,the more obvious this phenomenon.VPA showed that the changes in plankton communities in Huaxi Reservoir and Hailong Reservoir were mainly influenced by water temperature and eutrophication factors.The changes in planktonic community in Goupitan Reservoir were mainly influenced by water temperature and chemical factors.The driving factors of Huaxi Reservoir were water temperature,TP,permanganate index,and SD.The driving factors of Goupitan Reservoir were water temperature,NO_(3)^(−)-N,and pH.The driving factors of Hailong Reservoir were water temperature and TP.Nutrients and water temperature were the main factors affecting the stability of plankton communities in reservoirs.