چكيده به لاتين
The Helle River Basin is one of south and southwestern river basins in the country that because of its arid and semi-arid climate has faced difficulties in water allocation, especially for agricultural proposes. Because of occurrence of climate change it is expected that this water deficit will affect future development in water resources projects and amplify water related problems in the basin. In this Study, by developing a hydro-economical model consisting of a rainfall runoff module, a water allocation module and an economical assessment module, we have been able to assess the economical impacts of climate change on the water resources projects of the Helle River Basin. SWAT software package has been used as the rainfall-runoff module to simulate the hydrological processes of the basin. after calibration and validation steps using SWAT-CUP package, the output of this module have been fed into WEAP software package which acts as the water allocation module as inputs. After another calibration and validation step in the water allocation module, using LARS-WG5 software, future climate change impacts on weather data has been applied and was fed to the calibrated SWAT model as input data. In this part, climate change impacts on major river flows was assessed and resulted in up to 13, 17 and 20 percent decrease in short, mid and long term futures respectively. These time series data of river flows then were used in WEAP software to assess changes in crop production and the results were analyzed in the Economical Assessment module. Four distinct scenarios for development of the river basin was considered based on future proposed plans and the results show a significant increase of the net present value of crop production by completion of the entirety of proposed water resources projects, while by applying climate change conditions the net present value will decrease dramatically. In the end, it is shown that by applying climate change impacts on water resources, the development capacity of the river basin becomes more limited and the results necessitates the consideration of future climate conditions in proposing future water resources plans and projects in the country.
