Effects of soil environmental factors on the dissolution rate of karst in soils-A case study of the State Jinfo Mountain Nature Reserve, Chongqing

Abstract：Previous studies paid little attention to the influences of the factors in the soil environment on karst processes. Using the State Jinfo Mountain Nature Reserve in Chongqing as an example, field experiments were conducted and data collected for field standard limestone tablets and the CO2 concentration, moisture, porosity, pH, and organic matter content of soils. The influences of the soil environmental factors in different land-use patterns and their coupling on the dissolution rates of carbonate are studied. The results indicate the following: There is appreciable difference in average dissolution rates of limestone tablets. They are from the highest to lowest are as follows: bamboo land, woodland, grassland, shrub land and herbal shrub land. The dissolution rates of limestone tablets and pH show a good negative correlation, while the dissolution rate of limestone tablets shows a good positive correlation with soil moisture and porosity. The karst processes at top of Jinfo Mountain are stronger than those at the foot, which is related to the severest drought in a hundred years in Chongqing. The CO2 concentration, moisture, porosity, pH and organic matter content affect the dissolution rate of the limestone tablets, and in addition, the multi-variable coupling of the factors in the soil environment also affects the dissolution rate of karst.