Comprehensive study on saline-alkali soil amelioration with sediment of irrigation area in northeast China

To improve the main shortcomings of insufficient nutrients, high salinity and low productivity in saline-alkali soils, this study collected saline-alkali soil samples from Da'an City of Baicheng and sediment samples from the adjacent Qianguo irrigation district, measured their pH values and major element contents, designed and verified the improvement scheme of saline-alkali soil based on geochemical engineering principles. Results indicated that the pH value and various element contents of saline-alkali soil could be adjusted by adding sediment to make it close to reference soil. Both theoretical calculation and experimental determination (soil pH, mineral composition, functional group composition and crop growth) revealed that the optimal mixing ratio of saline-alkali soil and sediment was 2:1. The saline-alkali soil amelioration with sediment of adjacent irrigation areas was effectively, low-cost and environment-friendly. The geochemical engineering principle was applicable to the amelioration of saline-alkali soil, but the mixing ratio of saline-alkali soil and sediment in different areas should vary with the local conditions. Meanwhile, theoretical calculation could basically replace the experimental determination to simplify the actual engineering application process. This saline-alkaline soil amelioration method makes full use of the surrounding natural waste and has the advantage of adapting measures to local conditions.