Rehabilitation of degraded sodic soils in an arid environment by using residual na-carbonate water for irrigation

Studies on the rehabilitation of degraded sodic soils using residual sodium carbonate water (RSC 7.1 to 8.8 me L‐1) were performed. Its use together with gypsum treatment at 100% soil gypsum requirement plus the quantity of gypsum needed for neutralization of excess RSC in irrigation water was effective in lowering the soil SAR (6.4 to 10.7) and improved water infiltration. A higher level of gypsum could reduce the soil pH but the values were in alkaline range (pH 8.3–9.3) because of high RSC in the irrigation water. In the first year of gypsum treatment it was possible to establish the crop, and a moderate production of wheat (2,610 kg ha‐1) and raya (Brassica sp.) (2,000 kg ha‐1) was obtained in the second year.