石膏和腐植酸配施对干旱盐碱区土壤改良及棉花生长的影响

Effects of Combined Application of Gypsum and Humic Acid on Improvement of Saline-alkali Soil and Cotton Growth in Arid Areas

针对试验区盐碱土特点,选择石膏和腐植酸为盐碱土壤改良剂,通过石膏、腐植酸单施与石膏和腐植酸不同用量配施试验,分析了改良剂施用后土壤盐分含量和pH变化及对棉花株高、茎粗和产量的影响,优选出适宜于该试验区的最佳改良剂。试验结果表明,石膏和腐植酸质量配比9∶1组合在3000和4500 kg/hm^2施用量情况下,0~20 cm土壤降盐效果好于单独施用石膏或腐植酸处理;而单施腐植酸处理对棉花增产效果最好,较对照增产29.8%。综合来看,该地区较优的改良剂及用量为:石膏和腐植酸质量配比9∶1混合施用3000 kg/hm^2,其可使0~20 cm土壤含盐量较对照下降24.3%,棉花增产24%。

According to the characteristics of saline-alkali soil in the experimental area,the gypsum and humic acid used alone and combined to mitigate the negative effects of soil salinity on cotton growth.Soil salt content,pH,plant height,stem diameter and yield were measured during the cotton growth period in order to determine the optimal soil amendment for the test area.The results showed that 9∶1 of gypsum to humic acid with the application amount of 3000 and 4500 kg/hm^2 had the better desalination effect in 0–20 cm soil than those of gypsum and humic acid used alone.Humic acid used alone had the best effect on cotton yield,increased by 29.8%compared with CK(no amendment).In conclusion,the optimal soil amendment was gypsum combined with humic acid with a ratio of 9∶1 and with the application rate of 3000 kg/hm^2,it could decrease salinity in 0-20 cm soil by 24.3%and increase cotton yield by 24%compared with CK.