中文摘要：

为了提高真空抽提效率,最终得到用于稳定同位素分析的沙漠土壤水样,基于传统玻璃装置探讨最佳的抽提时间、加热温度和样品质量。研究结果显示,当加热温度低于105℃时,最短抽提时间Tmin后收集的水样与初始水样之间存在明显的同位素差异,而当加热温度≥105℃时不存在这种情况,因此从105℃到200℃的加热温度都可以完全提取沙漠土壤水。最短抽提时间随加热温度的变化而变化,也与沙漠土壤质量有关。基于试验结果与讨论,提出干旱-半干旱地区沙漠土壤水分抽提的最佳试验条件：1用于真空抽提的土壤样品应含3~5 g水;2加热温度应≥105℃;3最短抽提时间为30 min。

英文摘要：

In order to improve the extraction efficiency and to get unfractionated water from desert soils for stable isotopic studies, extractiontime, heating temperature and soil weight of the vacuum-distilled extraction were estimated on the conventional glass equipment in this study.The isotopic difference is obvious between the post-Tmin collected water and the initial water when the heating temperature is below 105 ℃,suggesting the remains of weakly bound water. But, this is not the case when the heating temperature is higher than 105 ℃. Therefore, theheating temperatures from 105 ℃ to 200 ℃ are all available to completely extract water from desert soils. The minimum extraction time varieswith the heating temperature, and is also associated with the weight and moisture of desert soil. The following extraction conditions arerecommended for desert soils in arid and semiarid areas： a） the soil, which is used to be extracted, should contain about 3-5 g waterregardless of its moisture and weight; b） the heating temperature should be higher than 105 ℃ and; c） the minimum extraction time isrequired to be 30 min.