Abstract:

River connectivity has a great influence on characteristics of watershed hydrological processes, water environmental condition and the capacity of lakes drainage storage, etc. At present, the connectivity of a riverlake system has become the new strategy to promote water safety management in our country. Drainage structure damage and increasing connectedness of rivers have become one of the most important causes of frequent floods and waterlogging in plain river network regions which are highly developed and deeply influenced by urbanization and human activities. Therefore through the analysis of the existing river connected evaluation method, we proposed a new river connectivity evaluation method of plain river network based on the flow resistance and hydrological processes. Based on the river system of three periods of 1990, 2003 and 2010, the proposed approach has been tested on a river network of the Yin southeast plain. The results indicated that the rivers connectivity decreased more significantly in 2010 than in 1990. At the same time, by analyzing and contrasting several rivers connecting evaluations methods, it can be seen that river connectivity evaluation method based on water flow resistance and the hydrological processes can evaluate rivers connectivity of the plain river network area better, and the calculation result is superior to that from other methods because it coincides better with the actual situation. The river network connectivity evaluation method based on water flow resistance and river hydrological processes can evaluate river connectivity and on the corresponding relationship to rainfallrunoff synthetically. It can well explain the influence the river connected degree on flood drainage, and river connected degree is higher, the ability of river flood and waterlogging drainage is stronger. The study can provide the reference for rivers connectivity quantitative evaluation of the plain river network area