A Simplified Model for Conjunctive Use of Water Resources for Control of Soil Salinization in Eli River Valley

Water is the major limiting factor in agriculture in arid and semi arid regions. Change in the hydrologic balance in irrigation areas has resulted in high water tables and salinization of soil. However, where suitable aquifers exist, groundwater pumping and irrigation application after mixing with fresh surface waters can control the secondary salinization of soil and water table depth and improve productivity of degraded land. In this study, the cause of soil salinization in Eli River Valley was analyzed by developing a simplified model for conjunctive use of surface water and groundwater. The model based on mass conservation of salt and water. It enables an estimate to be made of rootzone salinity for particular salinity level of groundwater being used in mixed with surface water. We found that the depth of groundwater recharge through leaching results in the secondary salinization of soil in irrigated area in arid zone, especially under saline groundwater conditions. The results of this study provide a scientific base for the improvement of water quality, sustainable water use and control of soil salinization in the study area.