Flow duration curve for evaluating ecosystem flow regulating functions in the Zambezi River Basin (Africa) uri icon

abstract

  • Wetlands and forests have strong effects on hydrological processes by changing the rate of evaporation, transpiration, and flow routing in a basin, which affects basin water management such as dam operations. This study aims to assess the flow regulating functions of wetlands and forests using a flow duration curve (FDC) approach. We firstly identify wetlands and forests which are gauged both upstream and downstream. Reference conditions were then established using nearby sub-watersheds that contain few/no wetlands/forests. By transferring reference flows to the target sites and comparing the FDCs for with and without wetland/forest conditions we then assess the hydrological impacts on flood attenuation and base flow maintenance. Results of a floodplain wetland suggest that it decrease flood flows and increase low flows. The extent of this function could be quantified which gives useful indications for water resources planning and management

publication date

  • 2012