Combined methods for comprehensive improvement of saline-alkali soil in Datong Basin

The research conducted for four years demonstrated that only the combination of several methods was able to improve saline-alkali soil. Hydrotechnics (e.g. well water for irrigation, combined utilization of well and drainage canal, open drainage together with underdrainage) lowered the ground water level from 2.05 m to 1.45 m. Employing chemical amendment (SN-01) for three years neutralized pH value from 8.43 to 10.2 in the tillage layer of soil. Also chemical amendment diminished salt content, expressed as electrical conductivity (EC). As a result, CO^2-₃ was disappeared; HCO^-₃ and Na⁺ contents in the soil were only 89.7% and 85.9% of original contents, respectively. Other amendments, such as sulfur-free gypsum, lignite, compost of furfural etc., had effective functions on saline-alkali soil. Salt content decreased 40% by means of suitable agricultural ways. Soil bulk density diminished and porosity increased. Organic fertilizer enhanced 21.8% organic matter. Total N was 1.5 times higher than that before its application. Suitable agricultural techniques and management played significant roles in keeping soil moisture, diminishing and avoiding salt damage to plants.