Abstract:
Soil humus fractions characteristics were analyzed for samples taken from Linqu and Mengyin Counties to study the humus composition and distribution characteristics in typical tobacco planting soils in Shandong. The results showed that soil humus carbon content was 7.99 and 5.83 g/kg, humic acid carbon content was 5.57 and 4.16 g/kg, H/F were 1.27 and 2.28 in Linqu and Mengyin, respectively. Humus carbon content, from high to low, was cinnamon soil > leaching cinnamon > brown soil > calcareous regosols > cinnamon soil > acidic regosols. The maximum was 8.21 g/kg and the minimum was 3.92 g/kg. Humus content and the content of each component in the two counties gradually decreased with soil depth, and decreased rapidly from the surface to the middle, then decreased slowly. H/F decreased firstly, then increased, finally decreased with soil depth in two counties.