Interaction Between Urbanization and River System in a Plain River Network Region

Abstract

River system changes are widely observed in urbanization areas, but the relationship between urbanization and river system is poorly understood. We investigate the interaction between urbanization and river system in a plain river network region. Results show that the structure and morphology of the river system became simplified. In most areas, the higher the initial river density, the more river channel loss occurs. The interaction between urbanization and river system consists of three stages: (1) with the development of urbanization, a large amount of low-order channels were encroached, filled, and transformed into construction land, (2) urban expansion and channel loss change the process of runoff generation and concentration and increase the risk of rainstorm and flood disasters, and (3) to relieve these negative effects, humans add main channels by widening and excavating. Low-order channels fall victim to urbanization. Effective measures, including legislation, must be taken to protect low-order channels in the process of urbanization.