Abstract:The evapo-geochemical barriers (EGB) in soils of arid-desert landscapes in Tianshan Mountains, Xinjiang may be divided into carbonate EGB, gypsum EGB, and soluble salt EGB, which are mainly composed of carbonatic soil, gypsic soil, and saline soil, respectively. These EGBs are distributed along Tianshan Mountains as a sequence of carbonate EGB, gypsum EGB, and soluble salt EGB from mountain to basin. In the carbonate EGB, the concentrations of Mn, Ti, Fe, V, Sc, Cu, Co, and B in soils were diluted and lowered as the result of the accumulation of dissociated CaCO3. In the gypsum EGB, B and Sr in soils were increased with increasing gypsum. In the soluble salt EGB, the accumulation of soluble salts always accompanied with an increase of B, and a decrease of Mn, Fe, Ti, V, K, Ba, Li, F, and Zn in soils due to the dilution of soluble salts. The EGB significantly affected the bio- availability of Fe, Cu, B, F, and Zn as well. The accumulation of dissociated CaCO3 in the carbonate EGB significantly decreased the bioavailability of Fe, Cu, and B, whereas the bioavailability of B increased with the concentration of soluble salts in soils. Wate-rsoluble F in the carbonate EGBwas high in the soils with high concentrations of CO32- and HCO3-. In addition, the bio-availability of Cu is higher in the soils with high organic matter than in the other soils. The bioavailable Zn has significantly positive relationship to the content of clay in soils.