低分子量聚丙烯酰胺对盐渍化土壤水动力参数的影响

通过室内模拟试验研究了低分子量聚丙烯酰胺在混合施用下对盐渍化土壤水分特征曲线、饱和导水率、水平扩散率的影响。结果表明:随着聚丙烯酰胺施用量的增加,盐渍化土壤的饱和导水率呈减小趋势且随着盐渍化程度加重减小程度逐渐减轻。土壤水吸力相同时,轻度盐渍化土壤聚丙烯酰胺施用量为0.25 g/kg时其持水能力最强,中度、重度盐渍化土壤施用聚丙烯酰胺0.5 g/kg时其持水能力最佳,聚丙烯酰胺对中度盐渍化土壤的持水能力的作用效果较好,重度盐渍化不佳。土壤含水量相同时,聚丙烯酰胺含量越高,土壤水平扩散率越小,且随着盐渍化程度的加重土壤水平扩散率减小幅度逐渐增大。

Influence of Low Molecular Weight Polyacrylamide on Soil Hydrodynamic Parameters

In this paper the effects of low molecular weight polyacrylamide on soil saturated hydraulic conductivity, water characteristic curve and horizontal diffusion rate of saline soil were studied. The results showed that with the increase of the content of polyacrylamide used in soil, the saturated hydraulic conductivity decreased gradually. Under the same soil water suction, the water capacity reached the maximum when 0.25 g/kg polyacrylamide applied in the slightly salinized soil, and as to moderately and severely salinized soil, water capacity reached to the maximum when 0.5 g/kg polyacrylamide applied. Under the same soil water content, with the increase of polyacrylamide, soil water horizontal diffusivity decreased and the magnitude of this reduction increased with the increase of the degree of salinization.