土壤环境因子对土下岩溶溶蚀速率的影响——以重庆金佛山国家自然保护区为例

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

通过野外溶蚀试片和测量土壤CO2浓度、水分、孔隙度、pH值和有机质含量的方法,探讨不同土地利用方式下土壤环境因子及其相互耦合对岩溶溶蚀速率的影响。研究结果表明,金佛山国家自然保护区不同土地利用方式下的平均溶蚀速率差异显著,总体表现为:竹林地>林地>草地>灌丛地>灌草丛地。不同土地利用方式下的土壤pH值与溶蚀速率呈很好的负相关,土壤水分含量、孔隙度与溶蚀速率呈正相关。山顶岩溶作用明显强于山下,这与重庆市百年一遇的大旱不无关系。土壤环境中CO2浓度、水分、孔隙度、pH值和有机质含量影响着岩溶溶蚀速率,同时这些土壤环境相互耦合也影响着岩溶溶蚀速率。

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.