关键词: 西藏, 酸性土pH, 交换性酸, 非交换性酸, 交换性盐基

Abstract: There are 9 soils types which include 70 soils profiles and 258 layers in Tibet. Based on the analytic data of the nine soils types, the distribution and acidity characters of acid soils are discussed by analytic method. The 1/5 soils area is acid soils in Tibet. The soil is mainly distributed in the southeast of Tibet. The soil pH is mainly determined by the Exchangeable Acid in Potential Acid, especially, exchangeable Al³⁺. However, nonexchangeable Acid is less impact. The dispel of acid functional group, which combines H and Al, is the main source of nonexchangeable Acid. The soil pH is also significant positive correlation with Base Saturation, which is mainly restricted by Exchangeable Base Ca²⁺.

Key words: Tibet, acid soil, exchangeable acid, nonexchangeable acidity, exchangeable base