Management of drainage waters from sugarcane cultivation in Khuzestan plain

Due to the limited water resources and recent droughts, as well as the adverse environmental effects resulting from the unprincipled release of agricultural drainage waters, the management and optimal utilization of agricultural drainage waters is essential. In this study, the possibility of reusing drainage water from sugarcane cultivation in Khuzestan plain for barley and eucalyptus cultivation and final discharge to artificial wetlands or evaporation ponds was investigated as a simulation program. In this regard, using desalination tests, the best empirical model of soil desalination was determined in the study area. Using an empirical desalination model, a simulation model was prepared to determine the final values of salinity of soil (ECf) for applying the depth percolation from irrigation of sugarcane. Then, based on the amount of sugarcane drainage water and water requirement of barley and eucalyptus, the area of arable land of these plants was determined. Also, by preparing a calculation program, the area of evaporative ponds or artificial wetlands was determined to drain the remaining drainage water from all crops. The results showed that using the drainage water of one hectare of sugarcane in the second year of cultivation, 0.5 hectares of barley can be cultivated and using the remaining drainage water of one hectare of sugarcane and drainage water of 0.5 hectare of barley, 0.22 hectare of eucalyptus planting. Finally, the area of drainage areas to create one hectare of evaporation pond (zero water balance), wetland (water level + 0.25 m) and wetland (water level height + 0.5 m), using the remaining drainage water amounts of sugarcane, barley and eucalyptus equal to 0.4348 m during a crop year was obtained equal to 5.715, 12.61 and 19.51 ha, respectively.