基于点-面两层结构的复杂网络方法评估海河流域水网连通性

河湖水系连通是指通过修建渠道、挖掘河道、改造湖泊等方式，将不同河流、湖泊之间相互连接起来，形成一个相互衔接的水系网络。基于复杂网络方法，从节点和子流域两个层面对海河流域水网的连通性进行分析。在子流域层面，用平均度指标评价流域连通度，用网络直径等指标辅助分析流域整体水系连通情况；在单个节点层面，用度指标、中介中心性指标分析流域水系各节点连通度的分布情况，实现了节点微观与流域宏观的结合。同时，引入聚类系数指标，获得每个子流域河网的空间分布特征。通过对研究结果的合理性评估，认为应用复杂网络方法能全面分析流域水系特征及连通情况，具有良好的应用前景。

Evaluation of water network connectivity using complex network method based on node-subbasin double layer structure

The connectivity of the river and lake system is a new concept of water treatment proposed in the new era. According to the concept, the rivers and lakes can be connected by constructing new canals and channels, also by the transformation of lakes, by which differnt rivers and lakes become an interconnected water network system. Based on the complex network method, the connectivity of the water network of the Haihe River Basin was analyzed from the two levels of the node and the subbasin. At the subbasin level, the connectivity of the basin was evaluated by the average index, and the overall water system connectivity of the basin was analyzed using the network diameter, average path length, etc. as supplementary indicators. At the level of a single node, the connectivity of each node in the basin was analyzed using degree index and betweeness centrality index. Therefore, the water system connectivity was analyzed from both node and subbasin levels, which realized the combination of microscopic and macroscopic perspectives. In addition, the clustering coefficent was also introduced for a better understanding of the spatial distribution characteristics of the river network in each subbasin. According to the rationality assessment of the results, it can be seen that the complex network method is conducive to the analysis of the characteristics and connectivity of the water system in the basin, and this method has excellent application prospects.