Abstract:
In order to understand the genetic characteristics and taxonomy of soils in south subtropical mountainous areas of China, the genetic characteristics of 10 representative soil profiles at different altitudes in the Luofu Mountains of south China were selected to investigate the physiochemical properties, the diagnosis layers, the diagnosis characteristics and the soil taxonomy based on the Chinese Soil Taxonomy. The results showed that the dry colors of soils were mainly 10YR, the textures belonged to loam, the ratios of silt to clay were 0.42-2.62 mainly less than 1.0 in most sections. Moreover, soil was highly acidic (pH of water extraction was 3.69-4.94), CEC was 4.43-25.68 cmol (+) kg
−1, soil base saturation (2.27%-16.25%) was low, exchangeable acid (1.35-6.41 cmol (+) kg
−1) was dominated by exchangeable Al
3+, and the saturation of Al in most soil layers was over 80%. The mineral elements in soils were mainly Si, Al and Fe. The values of
Sa and
Saf in clay were less than 2.0. Meanwhile, Al, Fe, P and Ti in B layer of each profile were enriched obviously in clay, and the Fe enrichment rate was slightly higher than Al. The altitudinal zonation of the soils in this region was consisted of Udic Ferrosols (< 800 m), Perudic Ferrosols (800-1200 m), and Perudic Cambosols (> 1200 m). The soils in the Luofu Mountains had the characteristics of desilication and Fe and Al enrichment, presenting the properties of obvious organic carbon accumulation, strong acidity, low base saturation and high Al saturation, which were classified into 2 soil orders, 3 suborders, 4 soil groups and 6 subgroups.