不同时期施用土壤改良剂对河灌区苏打盐碱地土壤及青贮玉米生长的影响

为明确盐碱地改良剂不同时期施用对河灌区盐碱地土壤的改良效果以及对青贮玉米生长的影响，采用田间试验方法，以青贮玉米‘瑞德2号’为供试作物，研究了河灌区重度苏打盐碱地国产DS、脱硫石膏、脱硫石膏配合DS 3种改良剂的秋季施用和春季施用对青贮玉米出苗率和鲜草产量的影响，分析了土壤(0~20 cm)pH、EC和碱化度的变化。结果表明：与对照（不施用改良剂）相比，施用改良剂处理的青贮玉米出苗率提高6.8%~72.7%，鲜草产量增加1223.2~28144.8 kg/hm2；土壤pH下降0.09~0.83，EC增加0.13~1.26 mS/cm，碱化度降低1.6%~19.8%；秋施和春施脱硫石膏、脱硫石膏配合DS均显著提高了青贮玉米的出苗率与鲜草产量。由此得出，3种盐碱地改良剂秋季施用效果均优于春季施用，其中以脱硫石膏配合DS的秋季施用效果最好。

Effects of Applying Saline-alkali Soil Amendments in Different Seasons on Silage Maize Growth in Saline-alkali Soils of the River Irrigation Region

The purpose of this study was to determine the effects of applying saline-alkali soil amendments on saline-alkali soils and on silage maize growth in different seasons (Spring or Autumn) in the river irrigation region, analysis the changes of pH, EC and alkalinity in the soils (0-20 cm). The field experiment using silage maize (Zea mays L. cv. Ruide 2) as trial crop was conducted to investigate the effects of applying Desulfurized gypsum, Guo-chan DS, and Desulfurized gypsum + Guo-chan DS in spring and autumn on the emergence rate and fresh yield in the severe soda saline-alkali soil. The results showed that, after application of soil amendments, the emergence rate of silage maize was increased by 6.8%-72.7%, fresh yield of silage maize was increased by 1223.2-28144.8 kg/hm2, soil pH reduced 0.09-0.83, EC value enhanced 0.13-1.26 mS/cm and alkalinity declined 1.6%-19.8% compared to the control. The emergence rate and fresh yield of silage maize was significantly increased after application of Desulfurized gypsum, and Desulfurized gypsum + Guo-chan DS in both autumn and spring. Application soil amendments in autumn had better effect of improving saline-alkali soils than in spring. The application in autumn of Desulfurized gypsum + Guo-chan DS had the best effect of improving saline-alkali soils among three soil amendments.