重度盐渍化土壤灌溉碱性淡水与施用改良剂效果研究

摘要：试验采用了灌水和施用改良剂相结合的方法对重度盐渍化土壤进行改良。试验采用2因素3水平组合设计，3个灌水量，3个改良剂施用量，12个处理，3次重复。结果表明：灌水量525m3/hm2土壤全盐量由1.72%降至0.48%～0.64%、灌水量750m3/hm2土壤全盐量降至 0.4%～0.6%。改良剂不同施用量与对照相比，土壤ESP下降幅度为2.83%～26.44%；土壤HCO3-下降幅度9.13%～43.47%；土壤Cl-下降幅度19.6%～29.9%；土壤SO42-增加幅度10.36%～58.22%；土壤Ca2+增加幅度0.68%～62.24%。灌水量750m3/hm2洗盐效果明显，改良剂施用量4500kg/km2防碱效果明显。但从节水和土壤盐分积累分析，灌水量525 m3/hm2、改良剂施用量3000 kg/km2为宜。

Effect of Alkaline Freshwater Irrigation and Amendment Application on Heavy Saline Soil

The study which combined desulfurized gypsum with alkaline freshwater irrigation was arranged to improve salinized soil,recycle desulfurized waste and save water resource.The experiment was designed with two factors and three levels,three irrigation amounts,three amendments application rates and three replicates.The results showed that the soil salt content was deceased from 1.72% to 0.48%-0.64% and 0.40%-0.60% for irrigation with 525 m3/hm2 and 750 m3/hm2 water,respectively.Compared with the control treatment,the soil ESP,HCO3-,Cl-,K＋,and Na＋ of amendment treatments were reduced by 2.83%-26.44%,9.13%-43.47%,19.60%-29.90%,and 11.80%-33.20%,respectively.However,soil SO42-and Ca2＋ were increased by 10.36%-58.22% and 0.68%-62.24%,respectively.The irrigation could enhance salt leaching significantly and amendment could modify soil salt components and decreased soil alkalization.Irrigation with 525 m3/hm2 water and application of amendment at 3000 kg/km2 were recommended in order to save water and alleviate soil salt accumulation.