土体有机重构对盐碱地土壤理化特征的影响

Effect of Organic Reconstitution of Soil on Physical and Chemical Characteristics of Saline Soil

摘要: 为了研究覆沙对盐碱地改良的效应，与2017年在富平中试基地设置覆沙厚度分别为0 cm、5 cm、7 cm、9 cm、11 cm、13 cm和15 cm的混合比例，在种植玉米收获后，分析测定了0~60 cm土层土壤的pH、电导率、全盐量、K⁺、Na⁺、CO₃^2-和Cl^-含量。结果表明：1) 各覆沙厚度处理下，同一处理不同土层土壤的pH、电导率和全盐量差异显著(P < 0.05)，且覆沙厚度为15 cm，改善效果最为明显(P < 0.05)。2) 每个处理下，随着土层深度的增加，K⁺离子含量大体都呈现先增加后减小的趋势；Na⁺离子含量随着土壤土层深度的增加变化不显著(P < 0.05)；覆沙15 cm处理下，CO₃^2-离子含量呈现先增加后减少的趋势，其它处理表现趋势不明显；覆沙15 cm处理下；Cl^-离子含量随着土层深度的增加，呈现先减小后增大的趋势。综上所述，覆沙15 cm整体改善土壤效果最佳，覆沙5 cm和7 cm对20~30 cm中层土壤理化性质改善效果最佳。

Abstract: In order to study the effect of overburden on the improvement of saline-alkali soil, and the mixing ratio of the overburden thickness of 0 cm, 5 cm, 7 cm, 9 cm, 11 cm, 13 cm and 15 cm were set in the fuling pilot test base in 2017. After planting corn harvest, pH, conductivity, total salinity, K⁺, Na⁺, CO₃^2- and Cl^- content of the soil layer of 0 - 60 cm were analyzed and measured. The results showed that: 1) Under the treatment of each overburden thickness, the soil pH, conductivity and total salinity of different soil layers under the same treatment were significantly different, and the overburden thickness was 15 cm, with the most obvious improvement effect. 2) Under each treatment, with the increase of soil depth, K⁺ content generally shows a trend of first increase and then decrease. Na⁺ ion content did not change significantly with the increase of soil depth. Under 15 cm of sediment covering treatment, the content of CO₃^2- ions showed a trend of increasing first and then decreasing, while other treatments showed no obvious trend. 15 cm of sediment coated; the content of Cl^- decreases first and then increases with the increase of soil depth. To sum up, 15 cm of sediment was the best overall improvement of soil, and 5 cm and 7 cm of sediment were the best improvement of physical and chemical properties of 20 - 30 cm middle soil.