Soil wettability is important for understanding a wide range of earth system processes, from agricultural productivity to debris flows and sediment fan formation. However, there is limited research considering how soil–water interactions, where the soil grains are naturally hydrophobic, might change in the presence of oil from natural hydrocarbon leakage or oil spills. Here we show how slippery liquid‐infused porous surfaces (SLIPS) apply to hydrophobic soils, by physical modelling of surfaces of different grain sizes and examining their interactions with water before and after impregnation with silicone oil. Using contact and sliding angle measurements and laser scanning fluorescence confocal microscopy, we demonstrate that soil SLIPS can be created with thick oil layers and thin conformal oil layers on median grain sizes of 231 μm and 32 μm, respectively. Until now, SLIPS have only been observed in human‐made materials and biological surfaces. The mechanisms reported here demonstrate that SLIPS can occur in natural granular materials, providing a new mechanism for water‐shedding in soil and sediment systems. Furthermore, the water‐shedding properties may be long lasting as conformal oil layers are stabilized by capillary forces. These results have important implications for understanding soil physics and mechanics where oil is present in a soil, and for agricultural hydrophobicity on shallow slopes.

中文翻译：

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光滑的注入液体的多孔表面：油对疏水性和超疏水性土壤的疏水性的影响

土壤的润湿性对于理解从农业生产力到泥石流和沉积扇形成的广泛的地球系统过程很重要。但是，考虑到天然烃泄漏或溢油引起的油污情况，土壤颗粒自然疏水的土壤与水之间的相互作用可能会如何变化，因此，有关研究的研究还很有限。在这里，我们通过对不同粒度的表面进行物理建模，并检查它们在硅油浸渍之前和之后与水的相互作用，来说明光滑的注液多孔表面（SLIPS）如何应用于疏水性土壤。使用接触角和滑动角测量以及激光扫描荧光共聚焦显微镜，我们证明土壤SLIPS可以在中值粒径为231的情况下通过厚油层和薄保形油层产生 μ m和32  μ分别米。到目前为止，SLIPS仅在人造材料和生物表面中被观察到。此处报道的机制表明SLIPS可以在天然颗粒材料中发生，为土壤和沉积物系统中的水流失提供了新的机制。此外，由于保形油层被毛细作用力所稳定，因此除水性能可能会持续很长时间。这些结果对于理解土壤中存在油的土壤物理学和力学以及浅坡上的农业疏水性具有重要意义。