Basin’s Water Resource Carrying Capacity Assessment in Climate Change Conditions Using Simulation-Optimization Approach; Case Study: Tashk-Bakhtegan basin

Water resources carrying capacity (WRCC) is a major component of resource and environmental studies and it is a management concept aimed at supporting sustainable socioeconomic development on a regional scale and catchment areas. Failure to pay attention to concepts such as the carrying capacity in the country's planning has led to the ineffectiveness of most programs. For this purpose, in the present study, it has been tried to use the simulation-optimization approach to determine the water resources carrying capacity in a pilot basin (Tashk-Bakhtegan Basin), considering the economic, environmental and Water resources in the historical periods (1985-2014) and terms of climate change (2045-2015) should be considered. In this regard, the Water and Soil Assessment Tool (SWAT) and the Genetic Algorithm are used. For this purpose, the outputs of three general circulation atmosphere models under RCP 2.6, 4.5, 8.5 scenarios have been used to assess climate change in this study. The results of the study indicate overloading of water resources due to increased crop area in all studied periods. Also, the water resources carrying capacity due to climate fluctuations and climate change in the examined period (1985 - 2045) has been declining, and from 2.6 billion cubic meters in the period (1985-2006) to 1.9 billion cubic meters. The most pessimistic climatic conditions are reduced.