宁夏红寺堡扬黄灌区次生盐渍化土壤改良成效研究

摘要

系统分析了利用脱硫废弃物和次生盐渍化土壤专用改良剂对宁夏红寺堡扬黄灌区次生盐渍化土壤的改良效应,结果表明:施用脱硫废弃物可以改善土壤理化性状,但改良效果不理想,同时施用脱硫废弃物和专用改良剂后土壤砂粒含量减少,粉粒、黏粒含量普遍增加;土壤体积质量平均增加5.34％、孔隙度降低5.61％,土壤pH和全盐均有不同程度的下降；施用脱硫废弃物和专用改良剂后土壤有机质和养分含量、枸杞产量都有较大幅度的增加,其中施用改良剂Ⅱ的增幅最大,但考虑改良剂原料成本后施用改良剂Ⅱ当年最终经济效益最大.相同改良剂秋施改良效果明显优于春施；施用量越大对土壤理化性状的改良效果越好,枸杞干果产量和直接经济效益也越高,但最终经济效益以施用量为11.25t/hm2的处理最佳.%The field experiment by planting Lycium barbarum L. In secondary stabilization soil improved by desulfurization gypsum and special soil amendment in irrigation region of Yellow River of Hongsipu, Ningxia. We analyzed the effect of improvement that indicated that desulfurization gypsum improved slightly physical and chemical properties of soils. Desulfurization gypsum and special soil amendment decreased sand content but increased silt and clay contents, and the soil bulk density increased by 5.34%, soil porosity decreased by 5.61%, average; both soil pH and total salt content were decreased by different degrees; organic matter, nutrients and crop yield increased significantly, and the effect of amendment Ⅱ was best. However, the net economical benefit of desulfurization gypsum and special soil amendment II were highest when the cost of soil amendments were considered. The improvement effect of amendment applied in autumn was bettor than in spring obviously; the improvement effect of physical and chemical properties of soils were better when the rate was higher, and the yield and direct economical benefit were higher. However, the net economical benefit was the highest of 11.25 t/hm2 treatment.