基于图论的平原河网区水系连通性评价--以常熟市燕泾圩为例

摘要

探讨河网连通性内涵，将河网连通性分为结构连通性和水力连通性；基于图论，将河网概化为图模型，以图模型可达性特征，利用Matlab对河网的结构连通性做出定量评价。考虑不同河道之间输水能力差异性，用河道水流阻力的倒数作为水流流通度，通过ArcGIS构建权值邻接矩阵，通过Matlab实现对河网的水力连通度的定量评价。以常熟市燕泾圩平原河网为例，对水系规划前后的河网连通性进行定量评价，结果表明，规划后的河网结构连通性和水力连通性均有所增加。%The implications of river network connectivity are discussed in this paper.River network connectivity is classified into two types: structural connectivity and hydraulic connectivity.Based on the graph theory, the river network is generalized as a graph model.According to the reachability characteristic of graph models, the river network’s structural connectivity is quantitatively evaluated by Matlab.With consideration of the difference in water conveyance capacity between rivers, the reciprocal of the resistance of river flow is regarded as the flow distribution, the adjacency matrix is built with ArcGIS, and the river network ’ s hydraulic connectivity is quantitatively evaluated with Matlab.A case study of the Yanjingwei Plain River Network, in Changshu City was conducted.The river network connectivity before and after river system planning was quantitatively evaluated.The results show that both the structural connectivity and the hydraulic connectivity of the river network increased after planning.