为揭示洞庭湖近十几年水文连通性的变化特征并对其未来变化进行预测，研究极端气候事件在洞庭湖水文连通性变化中作出的贡献，使用水文连通性指数法、ETCCDI极端气候指数、Hurst指数以及数理统计分析方法进行研究。研究结果表明：洞庭湖水文连通性整体呈现夏季>秋季>春季>冬季的特征，夏季、秋季、春季和冬季的整体连通性指数均值分别为0.95、0.88、0.81和0.63，且洞庭湖的水文连通性在近30年比较稳定；经持续性预测发现洞庭湖水文连通性Hurst指数均大于0.5，表示其在没有人类活动干扰的情况下会在未来呈延续下降的趋势；洞庭湖水文连通性指数随着水位增加逐渐增加且增速逐渐放缓，水位增加对其具有正向影响的边际递减效应；极端降水事件对洞庭湖水文连通性具有较为明显的正向影响，而极端气温事件对洞庭湖水文连通性影响作用较小。研究结果有助于充分认识洞庭湖水资源演变规律，对保障洞庭湖流域水资源安全具有重要的理论和现实意义。

The Dongting Lake basin is the region of the middle reaches of the Yangtze River that provides ecosystem regulation functions. The hydrological connectivity of the Dongting Lake basin experienced profound and complex changes as a result of climate change and human activities. China emphasizes that ecohydrological environmental protection should be put in the first place, and assessing the impact of the occurrence of extreme climatic events on the regional hydrological environment would be of great significance in protecting the stability of the regional ecohydrological environment. Previous study quantitatively characterizes and predicts the changes in the hydrological connectivity of Dongting Lake in the last decades. It is beneficial for us to fully understand the water resources evolution of Dongting Lake, to ensure the security of water resources which has a significant theoretical and practical meaning in the Dongting Lake basin.The hydrological connectivity index was applied to characterize the changes in the hydrological connectivity and to study the contribution of extreme climatic events. This study was carried out using the hydrological connectivity index method, ETCCDI extreme climate index, Hurst index, and mathematical and statistical analysis methods. The results showed that the hydrological connectivity index presented the characteristics of summer > autumn > spring > winter. From the remote sensing images extracted from the water body, it could be seen that the Dongting Lake hydrological network was characterized by inhomogeneity. It is found that the hydrological connectivity of Dongting Lake would continue to change excessively in the future according to the persistence prediction. Dongting Lake IIC and PC had an obvious response to extreme precipitation events, while Dongting Lake IIC and PC did not significantly respond to extreme climate events.These results indicated that the hydrological connectivity of Dongting Lake was relatively stable in the last three decades. Without the interference of human activities, the hydrological connectivity of Dongting Lake would continue the decreasing trend in the future. The hydrological connectivity index gradually increased with the increase of water level and the growth rate gradually slowed down, and the increase of water level had a positive influence on it with a decreasing marginal effect. Extreme precipitation events had a more obvious positive effect on the hydrological connectivity, while extreme temperature events had a smaller effect on the hydrological connectivity. This could be because heavy rainfall events may affect lake and river levels through direct water inputs, whereas extreme high or low temperatures may only indirectly affect lake and river levels through the evapotranspiration of water.