Abstract:

Abstract: The objective of this study was to enhance the yield of maize by improving chemical and physical properties of salinized fluvo-aquic soils with the combined amendments of gypsum and natural organic matter. The experiment utilized two formulas of soil amendments in which gypsum was combined with natural organic matter at different ratio, four application amounts, and a field with no amendments as control, total of nine treatments with three replicates each. Compared with control, soils with combined amendments decreased soil bulk density by 2.30%~11.86%, increased bulk porosity by 0.16%~10.52%, enhanced capillary porosity by 6.28%~26.30%, and reduced noncapillary porosity by 7.82%~52.38%. Different application amounts of the two amendment formulas, compared with control, at most reduced soil total salt amount, ESP, Na++K+ and Cl- by 127.27%, 95.69%, 185.5%, and 471.2%, respectively, and at most increased soil SO42- and Ca2+ by 481.19% and 478.25%, respectively. Soil amendments can not only improve soil physical structures and chemical ion compositions, but also provide crops with enriched humic acid and nutrients such as Ca and S. Compared with control, soils with combined amendments enhanced maize yield by 10.19% ~ 30.99%, and improved economic efficiency by 10.72% ~18.67%.