PE微塑料对土壤水分入渗的影响及入渗模型适宜性评价

为探究微塑料对土壤水分入渗过程的影响,通过室内土柱模拟试验,设置5组微塑料添加处理(0,1,2,4,6g/kg),研究了不同微塑料含量对湿润锋运移和累积入渗量的影响,并进一步评价了主要入渗模型在微塑料污染土壤中的适用性.结果表明,湿润锋运移速率随着微塑料含量的增加呈现出先减小后增加的特征,当含量达到T2时(微塑料含量2...

Effect of PE microplastics on soil water infiltration and suitability evaluation of infiltration model

In order to explore the effect of microplastics(MPs) on soil water infiltration, five groups of MPs addition treatments (0,1,2,4,6g/kg) were set to study the effects of different MPs contents on wet front transport and cumulative infiltration volume through indoor soil column simulation, and evaluate the applicability of the main infiltration models in MPs contaminated soil. The results showed that the migration rate of wet front decreased first and then increased with the increase of MPs content. When the content reached T2 (MPs content was 2g/kg), the migration rate of wet front was the lowest, which was 0.146cm/min. Compared to CK treatment, the migration rate of T2treatment was 10.1% lower (P<0.05). The cumulative infiltration volume also decreased first and then increased with the increase of MPs content. When the content reached T2, the cumulative infiltration volume was the least, which was 14.68cm. The reason may be that with the increase of MPs content, the influence of MPs on soil permeability increases, and the influence is the greatest when it reaches T2; When the content continues to increase, a new infiltration channel is formed by the MPs to accelerate the infiltration although the soil permeability decreases. The wet front propulsion model, Kostiakov model and Philip model have good fitting effects, and the determination coefficient R² are greater than 0.99, among which the wet front propulsion model has the best fitting effect. This study can provide a reference for the effect of MPs on soil water infiltration process and improve the simulation efficiency of the model.