河西绿洲灌区土壤调理剂改良盐碱土的效果初探

增施土壤调理剂是改良盐碱土壤的主要措施之一，但因盐碱土改良调理剂种类繁多，成分差别大，使用尚存争议，为给土壤调理剂在盐碱土改良中的应用及绿洲土壤盐碱化防治提供科学依据，选用5种不同成分土壤调理剂，在不改变河西绿洲灌区施肥水平和方式的前提下，研究了增施土壤调理剂对盐碱土的改良效果及对作物生长的影响。结果表明，增施土壤调理剂不同时期后，同土层各处理pH、EC值较不施土壤调理剂均有不同程度的降低，pH和EC值总体表现为增施硫黄粉9 000 kg/hm2 ＞ 增施磷石膏30 000 kg/hm2 ＞ 增施腐植酸1 200 kg/hm2 ＞ 增施禾康土壤调理剂45 kg/hm2 ＞ 增施盐地宝盐碱土改良剂45 kg/hm2 ＞ 不施用土壤调理剂。增施磷石膏30 000 kg/hm2、硫黄粉9 000 kg/hm2、腐植酸1 200 kg/hm2均可降低Na+、Cl-含量，增加Ca2+、SO42-含量，对盐碱土改良效果明显。各处理对玉米折合产量的影响由高到低依次呈现为增施腐植酸1 200 kg/hm2、增施硫黄粉9 000 kg/hm2、增施磷石膏30 000 kg/hm2、增施禾康土壤调理剂45 kg/hm2、施盐地宝盐碱土改良剂45 kg/hm2、不施用土壤调理剂。综合考虑认为，在河西绿洲灌区不改变当地施肥水平和方式的前提下，增施腐植酸1 200 kg/hm2和增施硫黄粉9 000 kg/hm2对河西绿洲灌区盐碱地的改良效果较好。

Preliminary Study on the Effects of Soil Conditioners on Saline-alkali Soil Improvement in Hexi Oasis Irrigation Area

Application of soil conditioners is one of the main measures to improve saline-alkali soil, due to the wide variety of soil conditioners as well as the large differences in composition, the application of soil conditioners for saline-alkali soil improvement is still controversial. To provide references for the application of soil conditioners in saline-alkali soil improvement and the prevention and control of soil salinizationin in Hexi Oasis Irrigation Area, 5 different soil conditioners with diverse components were chosen in this study to study their application effects on soil improvement and the impact on crop growth by adding conditioners without changing the fertilization. The results showed that after various periods of soil conditioner application, the pH and EC values of each treatment at the same soil depth decreased to varying degrees when compared to the control(no application of soil conditioners), and the overall pH and EC values were T4(additional application of sulfur powder at 9 000 kg/ha) > T1(additional application of phosphogypsum at 30 000 kg/ha) > T5(additional application of humic acid at 1 200 kg/ha) > T2 (additional application of Hekang conditioner at 45 kg/ha) > T3(additional application of Yandibao saline-alkali soil improver at 45 kg/ha) > the control. Contents of Na+ and Cl- in the soil were decreased whereas contents of Ca2+ and SO42- in the soil were increased under the treatements of T1, T4 and T5, which showed good effects on the improvement of saline-alkali soil. Effects of different treatments on the yields of maize ranked as T5 > T4 > T1 > T2 > T3 > the control. Comprehensively speaking, when fertilization is not altered, additional application of humic acid at 1 200 kg/ha and additional application of sulfur powder at 9 000 kg/ha showed ideal effects on the saline-alkali soil improvement in the Hexi Oasis Irrigation Area.