内蒙古河套灌区由于多年的灌溉不协调及其他原因,致使地下水位不断抬高,土壤盐渍化日趋严重,经多方面论证,解决土壤盐渍化的重要措施就是合理控制地下水位深度和实行排灌平衡,实现这一措施的主要方法就是要进行明沟排水。而实现明沟排水,打通排水系统的关键是合理确定明沟两侧边坡防止塌落阻水。本文从地质条件、土化学性质和土的物理力学性质角度对河套灌区的明沟塌坡原因进行分析,并提出稳定坡角 Due to many years of irrational irrigation and other reasons in Hetao Irrigation District in Inner Mongolia, groundwater level is continuously raised and soil salinization becomes more and more serious. After many arguments, an important measure to solve the problem of soil salinization is to control the depth of groundwater well and to implement the balance of irrigation and drainage The main way to realize this measure is to carry out ditch drainage. The realization of open ditch drainage, open up the drainage system is the key to determine the ditch on both sides of the ditch to prevent slump blocking water. Based on the geological conditions, the chemical properties of soil and the physical and mechanical properties of soil, the paper analyzes the causes of slope collapse in Ming ditch of Hetao Irrigation District,