基于周丛藻类群落结构的新疆额尔齐斯河生态健康评价

Abstract

周丛藻类对水环境变化较为敏感, 可迅速而灵敏的反映水质健康状况。本研究于2019年对额尔齐斯河周丛藻类群落结构和水环境特征进行了系统调查, 并运用周丛藻类生物完整性指数(Periphytic algae index of biotic integrity, P-IBI)对生态健康进行了评价。结果表明：额尔齐斯河周丛藻类有6门41属102种, 以硅藻门为主。周丛藻类密度和生物量的时间变化趋势为：9月>7月>5月, 空间分布趋势为中下游＞上游、支流＞干流。主成分分析(PCA)与典范对应分析(CCA)显示, 影响周丛藻类群落结构的主要环境因子有水温、溶解氧、高锰酸盐指数、氨氮、硝酸盐氮、pH、悬浮物, 不同月份的环境影响因素有所差异。额尔齐斯河周丛藻类多样性指数(H')、丰富度指数(D)、Pielou均匀度指数(J)的平均值分别为3.52、3.02、0.75, 显示额尔齐斯河流域整体水质为寡污或无污。P-IBI分析结果显示：5个采样点为健康状态, 1个采样点为亚健康状态, 3个采样点为一般状况, 1个采样点极差, 表明额尔齐斯河整体生态健康状况趋于良好。本研究可为额尔齐斯河的水环境监测提供一种有效手段, 并为该流域的水生态保护提供基础资料及理论依据。;Periphytic algae are sensitive to the changes of aquatic environment and can reflect the health status of water quality quickly. In this study, the community structure and water environment characteristics of algae around the Irtysh River were investigated systematically in 2019, and the biological integrity index of periphytic algae was used to evaluate the ecological health. The results showed that there were 102 species of algae belonging to 41 genera and 6 phyla, mainly Bacillariophyta. The temporal change of density and biomass for periphytic algae was September > July > May, and the spatial distribution was middle and lower reaches > upstream, tributaries > trunk stream. Principal component analysis (PCA) and canonical correspondence analysis (CCA) showed that the main environmental factors affecting the community structure of peripheral algae were water temperature, dissolved oxygen, permanganate index, ammonia nitrogen, nitrate nitrogen, pH and suspended matter. The average values of algal diversity index (H'), richness index (D) and Pielou evenness index (J) around the Irtysh River were 3.52, 3.02 and 0.75, respectively, indicating that the overall water quality of the Irtysh River basin is pollution-free or non-pollution. the results of P-IBI analysis showed that 5 sampling sites were healthy, 1 sampling site was sub-healthy, 3 sampling sites were general, and 1 sampling site was very poor, suggesting that the overall ecological health of the Irtysh River tended to be good. The results of this study can provide an effective measure for aquatic environment monitoring of Irtysh River and, meanwhile, provide basic data and theoretical references for the ecological protection of Irtysh River basin.