Analysis and modeling of soil shrinkage and swelling dynamics as a function of predrying intensity and frequency and its influence on soil hydraulic properties

关于收缩和/或膨胀过程中土壤孔隙结构变化的知识提高了对水流和溶质运移的理解和预测。土壤颗粒和团聚体的重新排列改变了原始的孔隙尺寸分布，特别是形成土壤裂缝。土壤裂隙导致土壤结构的不均匀，提高了大孔隙通量。然而，土壤基质中的土壤裂缝的几何形状在湿/干循环及其对水力特性的影响尚不清楚。因此，在这项研究中，我们调查的土壤裂缝的几何形状和二维收缩（即垂直和水平）收缩/膨胀频率和强度下的变化，并评估它们在多大程度上影响水力土壤特性。

Knowledge about changes in soil pore structure during shrinkage and/or swelling processes improves the understanding and prediction of water flow and solute transport. The rearrangement of soil particles and aggregates modifies the original pore size distribution, and especially forms soil cracks. Soil cracks lead to a non-uniform soil structure and improve macropore flux. However, the geometry of soil cracks within the soil matrix upon wetting/drying cycles and its influence on hydraulic properties is not clear. Therefore, in this study, we investigate the changes of the geometry of soil cracks and of two-dimension shrinkage (i.e. vertical and horizontal) under shrinkage/swelling frequency and intensity and evaluate how far they influence hydraulic soil properties.