Evolution of Soil Salinity on Alluvial fan, Alluvial Plain and Delta in Manas River Valley, Xinjiang, Northern China
Salt accumulation in the soil surface is a major cause of land degradation in the Manas River Valley of Xinjiang, China. To determine the changes of soil salinity in the alluvial fan, alluvial plain and delta, soil samples were collected from four farms across the entire study area, the salinity of soil solution was determined, and the historical records on soil salinity,groundwater depth and groundwater salinity were also collected. The results indicated that average groundwater table at the lower part of alluvial fan decreased from 1991 to 1996 and now stabilized between 2.0 m and 4.6 m (in some parts of this zone, the groundwater level was 1 m below the surface), but high level of groundwater salinity (19.93 g L-1 average) was dominant, and the concentration of salts in soil profiles significantly increased. Desalinization occurred in the soil layers of alluvial plain from 1982 to 2005, but the average groundwater level rose to 2.0 m and was approaching the critical value. Regarding the higher soil salinity in subsoil layers, this zone may be threatened by soil salinization in the near future. For the alluvial delta, average groundwater table increased to 1.95 m with the long-term irrigation, and at the same time the area of salinized land also increased. Additionally, observation reveals that the concentration of salts in soil surface was low, but soil salinity increased with soil depth. So salts accumulation may occur in the topsoil layers of the lower delta.
Xinjiang Manas River Valley Alluvial plain Alluvial fan Delta Soil salinity
Li Yuyi Tang Heng Zhang Fenghua Chen Fu
College of Agronomy and Biotechnology, China Agricultural University, Beijing 100094, China Key Laboratory of Oasis Ecology Agriculture of Xinjiang Production and Construction Corps, Shihezi 8
国际会议
北京
英文
73-81
2006-10-14（万方平台首次上网日期，不代表论文的发表时间）