通过对荒漠区荒地、绿洲区耕地及摞荒地厚层包气带剖面土壤水的含水率、易溶盐离子及稳定同位素(δD、δ18O)的测定和分析,对厚层包气带区土壤水的补给来源及地下水的垂向补给量进行了厘定.结果表明:荒漠区荒地、绿洲区耕地与摞荒地土壤含水率、易溶盐中氯离子与土壤水氢氧同位素在垂向上均呈现旋回变化,每个旋回经历了一次新水入渗补给的过程.绿洲区土壤水与荒漠区土壤补给水中的δD值为-124.10‰～-94.44‰,土壤补给水来源于冬季大气降水或降雪的入渗补给.绿洲内耕地区、摞荒地区及荒漠区地下水垂向入渗补给量分别为1.29～5.53mm/a、0.52～1.85mm/a及0.03～0.08mm/a.%The authors investigated the origin of soil water and vertical infiltration recharge of groundwater in thick unsaturated zone of arid area based on the characteristics of water content, stable isotopes (δD and δ18O) of soil water and soluble salt ions in soil. The results indicate that the vertical profiles of stable isotopes of soil water depict a cyclic variation as well as water content and chloride of soluble salt ions for the uncultivated regions in desert and cultivated and uncultivated regions in oasis. Each cyclic variation indicates one infiltration event that has involved mixture of newly infiltrated water and existing soil water. The lower value of Cl-content is consistent with the depleted values of δD in each cycle;δD of soil water varies from-124.10‰to-94.44‰, which suggests that soil water originates from precipitation or snow in winter in desert and in oasis. The vertical infiltration recharge varies in the ranges of 1.29～5.53mm/a, 0.52～1.85mm/a and 0.03～0.08mm/a respectively for the cultivated and uncultivated regions in oasis and the uncultivated regions in desert.
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