A review of the formation causes, ecological risks and water quality responses of metalimnetic oxygen minimum in lakes and reservoirs

溶解氧（DO）对湖库的生物地球化学循环、生态系统结构和功能起着至关重要的作用，也是评价水生态系统的敏感性指标.DO浓度的降低对水生态有着重要影响.结果显示，多数湖库在夏秋季热分层期间，由于温跃层较高的密度梯度、藻类衰亡和有机质的降解以及微生物的呼吸作用会消耗大量的DO，从而形成温跃层溶解氧最小值（MOM），甚至在该区域诱发厌氧状态.MOM可驱动浮游动物日夜垂向迁移，影响无脊椎动物和鱼类分布迁移模式及种群结构，破坏水体生态分布，致使生物非正常死亡，危害水体生态安全；此外，MOM也可诱发温跃层温室气体（CH4和CO2）大量形成，影响水源地水质，成为湖库生态安全隐患.目前对MOM所导致的生态风险和水质问题以及最终的控制方法已有较多研究成果，但缺乏综述性的研究.本文从MOM研究历史、研究方法、形成原因、生态风险及控制方法等方面进行论述，并展望今后研究热点，旨在推进MOM的相关研究进展，保障湖库生态平衡和供水水质安全.;Dissolved oxygen (DO) plays an important role in the biogeochemical cycle, evolution of ecosystem structure and function. It is also a sensitive indicator physical changes aquatic ecosystems. Previous studies suggested that most water source reservoirs or lakes could form metalimnetic minimum (MOM) during thermal stratification period summer autumn. Furthermore, anoxic anaerobic conditions can be induced this region. High density gradient metalimnion, aggressive consumption DO by degradation algae organic matters, respiration microorganisms are considered as main contributors. MOM restricts diurnal nocturnal migration patterns zooplanktons, disturbs vertical distribution invertebrates fish reservoirs. The existence will destroy ecological bodies lead to abnormal death organisms. In addition, significantly change dynamics greenhouse gases (CH4 CO2) affect quality supply well. Recently, series about have been published, but no comprehensive review reported. paper, comprehensively discussed from five aspects, including research history, causes, risks, responses control measures. future directions fields order promote relevant MOM, ensure balance supply.