Capillary rise is a significant contributor of soil salinity in extremely arid areas and is highly dependent on soil grains and total dissolved solids (TDS) in phreatic water. In this paper, experiments about effects of different grains of sand soil and TDS of phreatic water (1, 30, 100, 250 g/L) on capillary rise were conduced. The results showed that the height of capillary rise was steadily increasing in later stage of experiments and TDS had significant effects on capillary rise. For coarse sand, the higher TDS made the lower height of capillary rise. But for fine sand, the height of capillary rise of lg/L was obviously larger than others. The sequence of height from lower to larger of capillary rise in silt was 30, 100, 250 and lg/L. At the beginning of experiments about coarse sand, the higher TDS made the lower velocity of capillary rise, but other soil groups were not. Compared to high-TDS condition, the grain of sand soil was a more primary controlling factor of capillary rise. The research indicates that high-TDS not only changes the gravity of capillary water but also the pore size of soil during the period of capillary rise in fine sand.%为明晰极端干旱区高盐度潜水蒸发机理,指导盐荒地开发与水盐调控,开展了砂性土条件下,不同粒径及潜水矿化度(1、30、100、250g/L)组合的毛细水上升试验.结果表明,试验后期毛细水上升规律稳定时段:粗砂土柱,潜水矿化度越大,毛细水上升高度越小；细砂土柱,1g/L处理毛细水上升高度明显大于其他3组:粉土土柱,不同处理毛细水上升高度由大到小为:30、100、250、1g/L.试验初始阶段,除粗砂外并不表现为矿化度越大,毛细水上升速度越小的趋势.相比高矿化度,粒径是控制毛细水上升的主要因素.研究表明,土体颗粒较细时(细砂、粉土),高矿化度不仅改变毛细水重力,也使得土体孔隙结构发生不同程度变化,二者综合作用于毛细水上升过程.
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