Improving Physical and Chemical Properties of Saline Soils with Fly Ash Saline and Alkaline Amendment Materials

Abstract

Studies have demonstrated that the physicochemical properties of saline soils can be improved, and crop growth can be promoted by fly ash saline and alkaline soil amendment materials. Herein, the effects of fly ash saline and alkaline soil amendment materials on the physical and chemical properties of saline soil and growth conditions of Arrhenatherum elatius at room temperature were evaluated. Meanwhile, planting experiments of Zea mays L. were conducted in the demonstration field of saline–alkaline land amendment in Yinchuan, Ningxia. The results showed that the application of amendment materials significantly (p < 0.05) improved saline soil’s physical and chemical properties. The saline soil pH decreased from an average of 10.51 to 8.89; the Na+ content decreased from an average of 2.93 g·kg−1 to 0.7 g·kg−1 after 25 days of action. In addition, the soil bulk density decreased from an average of 1.49 g·cm−3 to 1.36 g·cm−3, and the total porosity increased by 15.60%. Soil available phosphorus and available potassium content also increased significantly, with mean values increasing from 6.74 mg·kg−1 and 173 mg·kg−1 to 58.30 mg·kg−1 and 330.76 mg·kg−1, respectively. In addition, the plant height and stem thickness of Arrhenatherum elatius increased from an average of 11.76 cm, 1.28 mm to 21.72 cm, 1.59 mm with the application of 2.5 wt% amendment material. The plant height and stem thickness of Zea mays L. increased from mean values of 210 cm and 21.94 mm to 315.7 cm and 26.75 mm, respectively, when 0.07 t·hm−2 of amendment material was applied in the field. Overall, it was concluded that applying fly ash saline and alkaline soil amendment materials improves the physicochemical properties of saline soils, reducing saline stress and promoting the growth of Arrhenatherum elatius and Zea mays L.