Research on Soil Fertility Quality under Different Land Use Types in Mountainous Areas of Chongqing

The aim of this study is to reveal the soil fertility status under different land use types in a small mountainous watershed in Chongqing, and to provide a basis for soil fertility management. Three different land use types were selected and a total of 81 samples were collected to analyze the soil nutrient status and fertility quality in a small mountainous watershed in Nanchuan District, Chongqing. The results showed that the soil in the study area was severely acidified, and forest land had the highest organic matter content. Total nitrogen, total phosphorus and available phosphorus were abundant in dryland, while total potassium and available potassium were generally lacking. The comprehensive soil fertility index ranged from 0.2 to 0.9, with an average value of 0.54. The soil fertility quality in the study area was moderately low, and the order of fertility quality under different land use types was ranked as dryland (0.57) > forest land (0.51)> paddy field (0.48). The higher fertility level in drylands indicated that the importance of human management measures and scientific soil fertilization treatment, while the higher fertility level in forested land than in unused agricultural land indicated the importance of proper returning farmland to forest.