Effects of climate change on the agricultural sector in the Kheirabad River Basin: Application of WEAP Software

Abstract

Introduction: Due to the wide and interaction effects of climate with different production sectors, today climate change is mentioned as one of the most important environmental challenges of the 21st century, which has serious economic consequences. Meanwhile, the agricultural sector is more affected by climate change than other sectors and agricultural production is directly related to these changes. In this study, an attempt was made to evaluate the effect of climate change on the agricultural sector of the Khairabad River Basin. Materials and Methods: In this study, the WEAP simulation model was used to evaluate the effects of climate change. The WEAP model is a water resources planning tool based on the principle of water balance and shows the various sub-basins, water demand nodes, infrastructure, water flows and water transmission channels that are all interconnected. The MABIA method in WEAP software is a suitable tool to simulate the effects of climate change. This method simulates water requirements and crop performance and allows users to consider the effects of climate change and available water on crop growth. Findings: The results noted that under the average climate scenario, the crop yields increased and their water requirement decreased. Meanwhile, the highest increase in yield is related to the barley and the shortest is the watermelon. However, with the changing temperature and precipitation conditions based on the pessimistic climate scenario, the crop yield of most products is lower than the base conditions. Also, under these circumstances, the water requirements of crops have also increased, and the change in wheat and barley water requirements are more than other products and are facing increasing water stress. The results revealed that, under the average scenario, the climatic conditions have more effect on the economic productivity index for barley, tomato, and cucumber. The change of the water productivity index for these crops was 25.19%, 24.98%, and 23.80%, respectively. In addition, the results confirmed that by applying the pessimistic climate scenario the water productivity index decrease in comparison with baseline. Conclusion: The results of this study showed that by applying a pessimistic climate scenario, the economic and physical productivity of water input will decrease compared to the baseline scenario for all products.