Minimizing freshwater usage for quality improvement of saline soils in semi‐arid regions

Abstract

AbstractWater supply and its proper management play a significant role in establishing an optimal water policy in semi‐arid regions. Also, soil plays a key role in earth as an environmental interface. However, soil salinity is usually a large‐scale problem, which adversely affects the environment resulting in many environmental difficulties. The practice of leaching is the inevitable method for improving saline soils. However, due to the diminishing trend of available freshwater resources, as well as the necessity of allocating good quality water for many ecological and environmental demands, leaching must be optimized towards using a minimum amount of water. This study aimed to (i) quantify the optimal water required for efficient salt leaching and (ii) derive a simple practical model for estimating leaching requirements. A large area of 33 000 ha with extreme salinity was selected and two field plot‐scale leaching experiments were conducted. Different mathematical schemes were derived. The derived logarithmic model provided better performance. Results indicated that one pore volume of water is sufficient to leach out 85% of salts from the soil profile of the studied areas. Applying this quantity of water will sustain and secure the environment from the main environmental problems resulting from soil salinization.