中文摘要：

采用干灰化法与离子交换树脂色谱法联用,建立了植物中氯的分离方法,消除了有机质对氯同位素测定的影响,能够满足氯同位素正热电离质谱法测定的需求,没有造成氯的损失和氯同位素的分馏。结果表明,青藏高原和山东两个地区的5种植物组织器官的δ37Cl变化范围为-1.79‰~4.77‰（平均值为1.20‰）,山东地区的两种植物器官的δ37Cl小于或接近于0‰,而青藏高原地区的两种植物的δ37Cl〉0‰,这说明山东地区的两种植物器官中相对富集35Cl,37Cl相对贫乏,而青藏高原地区的植物则相对富集37Cl,两个地区的植物具有明显的Cl同位素分馏差异,可能是由于植物的生长环境或植物吸收利用氯的迁移、生物生理效应差别引起的,为进一步利用氯同位素技术研究植物吸收利用氯的生物行为提供参考。

英文摘要：

A method using dry ashing combined with triple-phase ion-exchange chromatography was developed to enrich chlorine in the plant, which could eliminate the effect of organic impurities on the determination of chlorine isotope by thermal ionization mass spectrometry. In the procedure, the recoveries indicated that there was no loss of chlorine and no fractionation of chlorine isotopes occur. The results showed that the composition of chlorine isotope in the tissues of plants in Qinghai-Tibet Plateau area and Shandong area ranged from-1 . 79‰ to ﹢4 . 77‰ with an average of 1 . 20‰. δ37Cl values of the two plant samples in Shandong area not more than 0‰indicated that 35 Cl was enriched in the organs of the two plants andδ37Cl values in Qinghai-Tibet Plateau area more than 0‰ indicated the deficiency of 35 Cl. Chlorine isotope composition fractionated significantly in the plant samples or in different tissues of a plant. This may be caused by the differences of the medium where the plants grow, the transport of chlorine or the physiological effect in the uptake of chlorine by plants , which put forward a new insight for the further investigation of chlorine behavior in plant and the global cycling of chlorine in the biogeochemistry.