Loess lithology is an intrinsic factor of suffosion erosion, while climate, groundwater, structure, vegetation and manmade diathesis all are exterior factors.
黄土的巖性是黄土具有潜蚀能力的内在因素,而气候、地下水、构造、植被以及人为因素是其外在因素。
Due to the extensive pumping of groundwater, the range of phreatic fluctuation was enlarged and the suffosion was enhanced.