基于浮游植物完整性指数的阳澄湖生态健康状态评价

Ecological health status evaluation of Yangcheng Lake based on phytoplanktonic index of biotic integrity(P-IBI)

为探究在以中华绒螯蟹养殖为主的情况下阳澄湖浮游植物群落结构与湖泊生态系统健康状态,于2022年7月(夏)和12月(冬)进行2次浮游植物样品采集和水环境因子测定,构建浮游植物完整性指数(P-IBI)体系,评价阳澄湖健康状况。结果表明:P-IBI评价显示阳澄湖夏、冬季的健康状态分别为一般、健康状态;夏季健康状况从优至劣依次为东湖、西湖、中湖,冬季则为西湖、中湖、东湖。P-IBI与透明度、流速、硝态氮、总氮呈极显著正相关(P<0.01),与pH、水温、磷酸盐、叶绿素a和高锰酸盐指数呈极显著负相关(P<0.01)。水环境因子直接或间接驱动了浮游植物群落结构和生物完整性的变化。

In order to establish phytoplankton community structure and assess ecological health in Yangcheng Lake,where stocked densely with Chinese mitten crab,2 times of phytoplankton sampling and water environmental factors measuring were conducted in July(summer)and December(winter)2022.A preliminary phytoplanktonic index of biotic integrity(P-IBI)was developed to evaluate the health of Yangcheng Lake.Results showed that P-IBI evaluation showed the health status of Yangcheng Lake in summer and winter was average and healthy,respectively.In summer,the health status in descending order was east lake,west lake,and central lake,while in winter it was west lake,central lake,and east lake.P-IBI was significantly positively correlated with transparency,flow rate,nitrate nitrogen,and total nitrogen(P<0.01),and negatively correlated with pH,water temperature,phosphate,chlorophyll-a,and permanganate index(P<0.01).The variation of phytoplankton community structure and biotic integrity were driven directly or indirectly by water environmental factors.