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石膏,由于它的有效性和价格低廉,是应用得最多的改良钠质土的钙源和维持适当水分渗透性的电解质来源。一般认为,由于石膏溶解所释放的钙代换了交换性钠,使土壤水分性质得到改善。应用石膏增加土壤水分的渗透也是个古老的措施。澳大利亚在1921和1933年间在含有少量交换性钠(ENa<0.10)的土壤上进行的田间试验证明,表施石膏可减轻土壤结壳,增加水分的渗透,并增加作物产量。Deneen报告说1945年加里福尼亚San Joaguin谷地农民为了改善土壤透水性,在土壤中施入了270,000吨石膏。五十年代,在加利福尼亚中央谷地的东部,通常把石膏加到低矿化度的灌溉水中或邻近
Gypsum, due to its effectiveness and low cost, is the most widely used source of calcium source for improving sodium earth and electrolyte to maintain proper moisture permeability. It is generally believed that the soil moisture properties are improved due to the exchange of sodium released by the dissolution of gypsum. The use of gypsum to increase soil moisture penetration is also an ancient measure. Field trials conducted in Australia between 1921 and 1933 in soils containing small amounts of exchangeable sodium (ENa <0.10) demonstrated that gypsum dressing reduced soil encrustation, increased water infiltration, and increased crop yields. Deneen reported that in 1945, farmers in the San Joaguin Valley, California, applied 270,000 tons of gypsum to soil to improve soil water permeability. In the 1950s, in the eastern part of the central valley of California, gypsum was usually added to or adjacent to irrigation water of low salinity