Changes of salt accumulation in soil layers with different landforms in Manas River Valley in Xinjiang Region of China

Field sampling and investigation on groundwater table and groundwater electrical conductivity data in typical regions were conducted in Manas River Valley, in Xinjiang Region of China. The long-term salt accumulation changes in soil layers with different landforms including alluvial-proluvial fan, alluvial plain and delta were analyzed in order to supply a basis for soil amelioration in this region. The result indicated that for the above of alluvial-proluvial fan, the groundwater table was low and soil salinization was not serious. In the alluvial-proluvial fan edge, continuous salt accumulation was apparent in part of the cultivated land due to higher levels of groundwater table and electrical conductivity. In the alluvial plain, desalinization in surface layer was noticeable, but salt content in the subsoil layers was still high and the groundwater level rose and reached the critical value. For the delta part, salt accumulation would occur in the surface taking into account the increasing groundwater level under continuous cultivation. Lastly, it was predicted that soil desalinization would appear in the regions with effective irrigation and drainage system, but salt accumulation in some zones of alluvial-proluvial fan edge, alluvial plain and delta would continue in the near future.