Objective  This paper aimed to explore the effects of different soil amendments on salt ions distribution of alkalized solonchak under different water sources leaching, and to provide scientific basis for the coordinated regulation of water and salt in alkaline soil under shortage background of fresh water resources in Yinbei Irrigation area.

  Method  The effects of combined additions of different leaching water and soil amendments on main salt ions distribution of alkalized solonchak were discussed through the infiltration experiment of one-dimensional vertical soil column, which consisted of two main treatments of Yellow River water and farmland drainage water, and six sub-treatments of control (no amendments), phosphogypsum, phosphogypsum + humic acid, phosphogypsum + furfural residue, phosphogypsum + aluminum sulfate, phosphogypsum + furfural residue & aluminum sulfate.

  Result  Compared to those in Yellow River water leaching, soil Na⁺, Cl⁻ and SO₄²⁻ in farmland drainage water leaching could be leached to 40 cm depth below the soil surface, but the contents of CO₃²⁻ and HCO₃⁻ in 0 ~ 40 cm soil layer were increased. In 0 ~ 40 cm soil layer, under the combined addition of Yellow River water and soil amendments, the treatment of "phosphogypsum + aluminum sulfate" had the best performance in decreasing Na⁺ content, and the treatment of "phosphogypsum" had the best performance in increasing Ca²⁺ content and decreasing HCO₃⁻ content. While the treatment of "phosphogypsum + furfural residue & aluminum sulfate" had the best performance in decreasing Cl⁻ content. Under the combined addition of farmland drainage water and soil amendments, the treatment of "aluminum sulfate + furfural residue" had the best performance in decreasing the contents of Na⁺ and HCO₃⁻, increasing Ca²⁺ content, and controlling SO₄²⁻ content.

  Conclusion  For alkalized solonchak of Yinbei Irrigation District, it is recommended to use "phosphogypsum + aluminum sulfate" as soil amendment under Yellow River water leaching, and use "phosphogypsum + furfural residue" as soil amendment under farmland drainage water leaching.