腐殖酸对滨海黏质盐土持水性能的影响

【目的】研究腐殖酸对黄河三角洲黏质盐土持水性能的影响。【方法】通过压力膜法测定各处理不同水吸力下的土壤含水率,采用VG方程对土壤水分特征曲线进行拟合,分析土壤水分特征曲线;通过KSAT饱和导水率仪测定土壤饱和导水率,分析腐殖酸配施量与饱和导水率的关系;通过不同腐殖酸配比下黏质盐土持续蒸发试验,分析腐殖酸配施量与蒸发的关系。【结果】黏质盐土配施腐殖酸后,土壤水分特征曲线发生明显变化。各腐殖酸配施量下黏质盐土水分特征曲线均高于T0处理;土壤水分常数明显提高,其中T2处理和T5处理配量下提高显著;饱和导水率明显提高,且T2处理和T5处理提高显著,与T0处理相比分别提高36.96%和56.92%;结合6h和12h累计蒸发量结果,T2-T4处理蒸发量较小,其中,T4处理蒸发量最小,但腐殖酸添加量对土壤水分蒸发影响不显著。【结论】腐殖酸能有效提高土壤持水能力,且T2处理下黏质盐土持水能力最强。

Effects of Humic Acid on Water Holding Properties of Clay Solonchak

【Objective】 The purpose of this paper is to explore the effect of humic acid on water holding capacity of clayey saline soil in the Yellow River delta.【Method】 Taking humic acid and clay solonchak as experimental objects, the soil water content under different water suction of each treatment was measured by pressure film method. Soil water characteristic curve was fitted by VG equation, and soil water characteristic curve was analyzed. The saturated water conductivity of soil was measured by KSAT saturation water conductivity meter, and the relationship between the amount of humic acid and saturated water conductivity was analyzed. The relationship between the amount of humic acid and evaporation was analyzed by continuous evaporation test of clay solonchak with different proportion of humic acid.【Result】The characteristic curve of soil water in clay solonchak with humic acid was changed obviously. Among them, the water characteristic curve of clay solonchak under the combined application of humic acid was higher than T0. Soil water constant increased obviously, among which T2 and T5 increased most obviously. The saturated water conductivity increased obviously, particularly for T2 and T5 increased with 36.96% and 56.92%, respectively, when compared with T0. Soil evaporation changed significantly. It was found that the evaporation capacity of T2-T4 was small, of which T4 was the smallest. However, from the significant analysis, the amount of humic acid added has no obvious effect on soil water evaporation.【Conclusion】 Humic acid can effectively improve the water holding capacity of soil, and the clay solonchak with T2 treatment has the strongest water holding capacity.