The parameterization of soil hydraulic properties (i.e., porosity and hydraulic conductivity) remains an important source of uncertainty in land-surface and large scale hydrological models, especially for shrink-swell soils, whose soil properties continuously change over time. Much research in shrink-swell soils has been devoted to understanding the relation between soil type, water content, shrinking and cracking, and water retention and hydraulic conductivity curves as well as developing suitable vadose zone hydrological models to estimate the impact on water flow and contaminant transport. However, little is known about the feedback of the shrinking and cracking on surface hydrology and its potential effects on agricultural production and land-atmosphere interactions. Here, using a probabilistic theoretical model linking shrink-swell properties to the soil moisture dynamics at soil matrix to pedon scales, we analyze the two-way interaction between shrinking/cracking status and soil moisture and analyze the impact of shrinking on hydrologic fluxes (i.e., evapotranspiration, percolation). Relying on data from Ships clay soils in Texas, the analysis of the probability density function of soil moisture for various shrink-swell properties and rainfall regimes reveals that shrinking overall contributes to lowering the pedon-scale soil moisture and prolonging the persistence of dry soil moisture states. This persistence of dry states is also associated with a shorter memory timescale in shrink-swell soils. Our results shed light on the impact of shrinking on surface hydrology and, given the expected climate change, calls for more research focusing on land-atmosphere interactions and the potential effects on the persistence of droughts.

土壤水力特性（即孔隙度和导水率）的参数化仍然是地表和大尺度水文模型中不确定性的重要来源，特别是对于收缩膨胀土壤，其土壤特性随时间不断变化。关于收缩膨胀土壤的大量研究致力于了解土壤类型、含水量、收缩和开裂、保水性和导水率曲线之间的关系，以及开发合适的渗流带水文模型来估计对水流和污染物的影响运输。然而，人们对收缩和破裂对地表水文的反馈及其对农业生产和土地-大气相互作用的潜在影响知之甚少。在这里，使用将收缩-膨胀特性与土壤基质到脚尺度的土壤水分动态联系起来的概率理论模型，我们分析了收缩/开裂状态与土壤水分之间的双向相互作用，并分析了收缩对水文通量的影响（即、蒸散、渗滤）。依靠来自德克萨斯州船舶粘土的数据，对各种收缩-膨胀特性和降雨情况下土壤湿度的概率密度函数进行了分析，结果表明，整体收缩有助于降低地面土壤湿度并延长干燥土壤湿度的持续时间状态。这种干燥状态的持续存在也与收缩膨胀土壤中较短的记忆时间尺度有关。我们的研究结果揭示了面积缩小对地表水文学的影响，并且考虑到预期的气候变化，呼吁开展更多研究，重点关注陆地-大气相互作用以及对干旱持续性的潜在影响。