关键词: 沙漠公路, 潜水埋深, 滴灌, 水盐, 影响因素

Abstract: Tarim Desert Highway controls the lifeblood of communications in oil and gas exploration and development， which is the first and longest graded highway across shifting sands in the world. But it was still suffering from sandstorms， shelterbelts that flanked the road were built to ensure the road to operate smoothly. The research on distribution of soil water and salt in the shelterbelts makes great significance for the excellent performance of sheltbelts. A lot of work has been done which focuses on the roles of irrigation regime， vegetation and so on while the behavior of water table depth has been ignored. In this research， three profiles where the water table depths were 3 m， 7.3 m and 13.7 m were chosen in order to emphasize the role of water table depth. The three sampling sites are labeled pl， pm and ph. Clay layer exists in ph ranging from 1.8 m to 2.2 m which can also be used for implying the soil material’s effect in characteristic of soil water and salt. Moreover， some sampling work was done between the sampling sites in pm where was far away from plants and drip irrigation. This profile called pm0 in compare with pm could confirm the effect of plants and irrigation. Water content was got by drying method and salt data was tested in means of IC， ICP-MS. The factors of soil water and salt are discussed systematically through sampling and analysis， especially the distribution of soil water and salt under different water table depths along the Tarim Desert Highway. Some data takes great significance and some conclusions are listed as follows：（1）The trend of soil water content first decreases and then increases while the variation of soil salt is not obvious. Therefore， the water depth should be considered in setting up irrigation scheduling. （2）From the diagram of variation of soil water content along the depth， the maximum height of capillary rise of sand is concluded about 1.8 m. （3）The clay plays an important role in water accumulation and salt collection which reflects on that the water content and salt concentration are extremely high in the clay layer in ph. （4）The affected depth of irrigation water is 1.2 m. Irrigation water provides the source of infiltration and eluviates the salt， as a result， the moisture is higher and salinity is lower in upper soil layer with salt accumulates in deeper soil layer. Soil water is higher in pm than that in pm0 within 1.2 m except at 1.0 m， similarly， the salt concentration is lower in pm than that in pm0 within 1.2 m except at 0.8 m. So the irrigation scheduling should be adjusted when the affected depth changes with the growth of the plants. All of this are of great importance in interaction of groundwater and vadose zone， building reasonable irrigation scheduling and making effective use of groundwater.

Key words: Tarim Desert Highway, water table depth, drip irrigation, water and salt, factors