白洋淀是华北地区最大的天然淡水湖泊湿地和重要的生态功能区，在自然和人为驱动影响下，生态系统呈明显的退化趋势。通过对白洋淀流域生态水文过程演变分析，剖析了其生态系统退化的特征及驱动机制。气候干旱是白洋淀生态系统退化的环境背景条件，而上游水库的截流、水利工程的建设及水资源的开发利用等自然、人为因素的耦合作用，加速了白洋淀生态系统退化的过程。基于白洋淀生态系统退化的特征和驱动机制，从流域生态水文过程演变出发，为湿地的保护提出了措施和建议。

he Baiyangdian Lake is the largest freshwater lake and an important aquatic ecological function region in north China.Under the natural and artificial influences, its ecosystems has being obviously degraded. This paper discussed the ecosystem degradation and its driving mechanism based on the evolution of the ecohydrological process in the Baiyangdian Lake basin. The climate aridity is the natural background of the ecosystem degradation, but upstream water interception,hydraulic engineering and the utilization of water resources are the inducing factors to accelerate the wetland degradation. Finally comprehensively considering the present state of ecosystem degradation and its driving mechanisms, measures and proposals are put forward to protect the Baiyangdian Lake from the perspective of ecohydrology.