Fissures and paleosols are important factors affecting the slope stability of loess. However, the mechanism of water and air migration in the unsaturated zone of loess induced by fissures and paleosols remains unclear. In this study, discontinuous irrigation experiments were conducted using a sand tank and Marriott bottle. The soil- water content (SWC) patterns and pressure differences, under the influence of fissures and paleosols, were observed using the EC-5 moisture sensor and MPXV5010DP differential pressure sensor. The results showed that the fissures are the dominant channels of water infiltration and air exchange, while paleosols and closed soil boundary conditions can significantly impede the downward transport of water and air. During irrigation, SWC near the fissure and paleosol increased rapidly from less than 10–30%, reaching a maximum value of 35% above the paleosol. On the other hand, the maximum pressure difference in the upper part of the paleosol exceeded 1,000 Pa, which is significantly higher than that observed in the lower part. The stability of soil around fissures and paleosols decreased sharply due to high SWC and pressure differences, which may induce landslides after long-term irrigation. This study provides a theoretical basis for revealing the formation mechanism of landslides in loess irrigation areas and preventing landslide disasters.

裂隙和古土壤是影响黄土边坡稳定性的重要因素。然而，裂隙和古土壤对黄土非饱和区水气运移的机制尚不清楚。在这项研究中，使用沙缸和万豪瓶进行了不连续灌溉实验。使用 EC-5 湿度传感器和 MPXV5010DP 差压传感器观察受裂缝和古土壤影响的土壤含水量 (SWC) 模式和压力差。结果表明，裂隙是水分入渗和空气交换的主要通道，而古土壤和封闭的土壤边界条件会显着阻碍水分和空气的向下输送。在灌溉过程中，裂隙和古土壤附近的 SWC 从不到 10% 到 30% 迅速增加，在古土壤之上达到最大值 35%。另一方面，古土壤上部的最大压差超过1000 Pa，明显高于下部。由于高SWC和压力差，裂隙和古土壤周围土壤的稳定性急剧下降，长期灌溉可能导致滑坡。本研究为揭示黄土灌区滑坡的形成机制和防治滑坡灾害提供了理论依据。由于高SWC和压力差，裂隙和古土壤周围土壤的稳定性急剧下降，长期灌溉可能导致滑坡。本研究为揭示黄土灌区滑坡的形成机制和防治滑坡灾害提供了理论依据。由于高SWC和压力差，裂隙和古土壤周围土壤的稳定性急剧下降，长期灌溉可能导致滑坡。本研究为揭示黄土灌区滑坡的形成机制和防治滑坡灾害提供了理论依据。