The study looked at how different types of land use affect soil quality in Jiuquxi Ecological Protection Area. They analyzed soil properties like density, pH, organic carbon, and nutrients in five land use types. The results showed that soil quality varied significantly between the land use types. Secondary forest had the best soil quality, while tea plantations had the lowest. The study suggests that planting broad-leaved forests can help improve soil quality in areas with good water and heat conditions.