PAM对土壤物理性状以及水分分布的影响

Effect of PAM on soil physical properties and water distribution

为了研究聚丙烯酰胺(PAM)在黄土高原自然条件下对土壤物理性状和水分分布的影响,采用表面撒施的方法研究了12个不同处理小区的土壤体积质量、饱和导水率以及水分分布的变化。结果表明,在0～2g/m2范围内添加PAM可以减小土壤体积质量增加土壤饱和导水率,但用量超过2g/m2土壤体积质量开始增加。饱和导水率开始降低。在0～3g/m2均可用二次曲线进行描述,相关系数达到95%以上。表层土壤含水量随着PAM添加量的增加而升高,20～60cm土层土壤含水率随着PAM用量的增加出现交叉现象,60～100cm土层随着PAM用量的增加而增加,在2g/m2用量时达到最高,再增加PAM用量土壤含水率反而有降低趋势。100cm以下土层变化不明显。该研究为探明PAM在黄土高原地区的适应性和大规模应用提供依据。

In order to study the impact of applied polyacrylamide（PAM）on the soil physics and the distribution of soil water content under the natural condition,an experiment and research on eleven various PAM amounts plots of Alfalfa and one bare plot have been studied.The results showed that during the 0-2 g/m^2 of PAM amount,the bulk density decreased with increasing amounts of PAM but the saturated hydraulic conductivity increased.The bulk density increased and the saturated hydraulic conductivity decreased when the concentration of PAM was higher than 2 g/m^2. During the range of 0-3 g/m^2 the changes between the bulk density,saturated hydraulic conductivity and concentration of PAM could be modeled by quadratic equation.The surface soil moisture increased with the increasing amounts of PAM. There were no significant difference about the soil moisture between 20-60 cm and 100-200 cm depth,while the soil moisture increased in 60-100 cm with the increasing amounts of PAM in the range of 0-2 g/m^2 but decreased when the concentration of PAM was higher than 2 g/m^2 .