Sustainable Water Management for Agriculture to Mitigate Climate Change Effects

Abstract Water scarcity, intensified by climate change and anthropogenic accomplishment, poses a critical task to worldwide sustainability. Iraq is one of the countries that has experienced severe water shortages due to the impacts of climate change and lack of water resources management. The most significant impacts of climate change are the availability and contamination of water resources. The main goal of this study is to develop a methodology to mitigate the effects of drought by utilizing saline water from the Main Outfall Drain (MOD) with the integrated WATSUIT model and Geographic Information System (GIS). After assessing the physical and chemical properties (pH, TDS, EC, Na, Mg, and Ca) at five monitoring stations (Baghdad, Hilla, Diwaniyah, Nasiriyah, and Basra) that have been selected along the MOD irrigation according to Iraqi and global criteria, the study determined that the water quality is unsuitable for drinking but adequate for irrigating salt-tolerant crops. The accumulated salinity at a steady state was estimated using the WATSUIT model. The results indicated that Basra’s water could not be used even at the highest washing requirements, while other sites were deemed acceptable with washing needs of (0.1) In comparison with salinity levels, the water in Al-Basra was found to be unusable even at maximum washing needs of 0.4. However, a significant improvement in the salinity levels was observed in Al-Diwaniyah at an LF of (0.2) Nevertheless, salinity levels in Al-Nasiriyah remain high, even at LF values between 0.2 and 0.4. Additionally, the total dissolved salts mostly exceed 2000 ppm, indicating the potential for growing salt-tolerant plants. The study concludes that using rainwater harvesting for soil washing, along with the saline water from the MOD, can help mitigate the impacts of climate change, remove salts from soils, and support the irrigation of salt-resistant crops.