Understanding the effect of the top soil layer on surface evaporation and water distribution is critical to modeling hydrological systems. However, the dependency of near‐surface soil moisture and fluxes on layering characteristics remains unclear. To address this uncertainty, we investigate how the arrangement of soil horizons affects the evaporation and soil moisture, specifically, the near‐surface soil moisture, through the combination of numerical simulations and evaporation experiments. The characteristics of fluxes and moisture from different soil profiles are then used to understand the soil layering conditions. Results show that the top soil layer can significantly affect the evolution of soil moisture profiles and evaporation dynamics, the extent of which depends on the layering sequence, thickness, and properties of each layer. The soil systems consisting of a thick coarse (C) layer overlying a fine (F) layer, or a very thin F layer overlying a C layer exhibit near‐surface moisture, temperature and fluxes nearly identical to that of a homogeneous C system; in these cases, a homogeneous C soil could be used to represent the above two layered systems. However, some soil profiles cannot be described by a single set of soil properties, nevertheless, they show distinct characteristics that can serve as indicators for soil layering conditions, e.g., “first slowly then rapidly” decreasing dynamics of near‐surface soil moisture. As some characteristics are not unique to layered soil, the combined information including the near‐surface soil moisture defined at different depths and evaporation behavior of an entire drying cycle can be used to better characterize the layering conditions.

中文翻译：

---

表土层对水分和蒸发动力学的影响

了解顶部土壤层对地表蒸发和水分布的影响对于模拟水文系统至关重要。然而，尚不清楚近地表土壤水分和通量对分层特性的依赖性。为了解决这种不确定性，我们通过数值模拟和蒸发实验的结合，研究了土壤层位的布置如何影响蒸发和土壤水分，特别是近地表土壤水分。然后使用来自不同土壤剖面的通量和水分特征来了解土壤分层条件。结果表明，表层土壤可显着影响土壤水分剖面和蒸发动力学的演变，其程度取决于分层顺序，厚度和每一层的性质。土壤系统由覆盖在细密（F）层上的粗大粗（C）层或覆盖在C层上的非常薄的F层组成，其近地表水分，温度和通量与均质C系统几乎相同。在这些情况下，可以使用均质的C土来代表上述两层系统。但是，某些土壤剖面不能用一套土壤性质来描述，但是它们表现出独特的特征，可以作为土壤分层状况的指标，例如“先缓慢然后迅速”降低近地表土壤水分的动态。由于某些特性并非分层土壤所独有，