Characterization of Evolution Stages, Groundwater and Soil Features of the Mud Forest Landscape at Qian-an (China)

The research on geological landscape has received more and more attention worldwide. The National Geological Park of Qian-an mud forest, located in Qian-an Country, Songyuan City (Jilin Province, China) is a rare natural geological landscape formed by erosion. Mud forest landscape has undergone long-term geological processes, and it is still in continuous evolution due to subsurface erosion. In the process of the mud forest landscape formation and evolution, distinct stages have been recognized. The subsurface erosion factors of the mud forest area were identified by groundwater and soil samples characterization, and the mechanism of the formation of the mud forest is studied. Results show that the occurrence of subsurface erosion is controlled by four factors: (1) The head difference of terrace increases due to geological structure, (2) The dry and cold paleoclimate increases the accumulation of soluble salts. Concentrated precipitation in the short term also promotes subsurface erosion. (3) The high content of sodium ions in groundwater promotes the dispersion of soil, and (4) Loess-like soil is characterized by high porosity, low plasticity, and dispersibility.