Hydroxypropyl methyl cellulose (HPMC), a potential soil improver with the ability to hold water, has practical applicability in alleviating soil and water nutrient loss. By using Cl⁻ as tracer ions, we evaluated the effects of different HPMC viscosities on soil water infiltration characteristics and conservative solute migration characteristics. Hydroxypropyl methyl cellulose with viscosities of 2 × 10⁴, 6 × 10⁴, 10 × 10⁴, and 20 × 10⁴ mPa s⁻¹ was selected. Experimental results revealed that the cumulative infiltration amount, wetting front migration distance, and infiltration rate decreased significantly with increased HPMC viscosity. The addition of HPMC delayed the soil solute transport process, and HPMC with a higher viscosity caused greater soil solute transport delay. Both the convection‐dispersion equation (CDE) and the two‐region model (TRM) accurately simulated solute transport, but the simulation accuracy of the TRM was higher. Results of parametric fitting based on the TRM indicated that the average pore water velocity, hydrodynamic dispersion coefficient, and dispersion degree decrease with increased HPMC viscosity. The average pore water velocity decreased by 13.6–28.2% relative to the control group (CG). Compared with the CG, the water content ratio in movable water of HPMC groups changed irregularly with an increase in viscosity. The mass exchange coefficient increased significantly compared with the CG, with an irregular trend. These data will be useful in the application and promotion of HPMC as a soil improver.

中文翻译：

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羟丙基甲基纤维素对土壤的渗透和保守的溶质运移特性

羟丙基甲基纤维素（HPMC）是一种具有保持水分能力的潜在土壤改良剂，在减轻土壤和水分养分流失方面具有实用性。通过使用Cl ^-作为示踪剂离子，我们评估了对土壤水分渗透特性和保守的溶质迁移特性的不同的HPMC的粘度的影响。以2×10粘度的羟丙基甲基纤维素⁴，6×10 ⁴，10×10 ⁴，和20×10 ⁴毫帕·秒^-1被选中。实验结果表明，随着HPMC粘度的增加，累积入渗量，润湿前移距离和入渗速率显着降低。HPMC的添加延迟了土壤溶质的运输过程，而粘度较高的HPMC造成了更大的土壤溶质运输延迟。对流扩散方程（CDE）和两区域模型（TRM）均能精确模拟溶质运移，但TRM的模拟精度较高。基于TRM的参数拟合结果表明，平均孔隙水速度，流体动力分散系数和分散度随HPMC粘度的增加而降低。相对于对照组（CG），平均孔隙水速度降低了13.6–28.2％。与CG相比 随着粘度的增加，HPMC组的可动水中的含水率无规律地变化。与CG相比，物质交换系数显着增加，并且具有不规则的趋势。这些数据将在HPMC作为土壤改良剂的应用和推广中有用。