The specific activity and distribution of 90Sr in desert plants benefit not only to the assessment of its pollution situation but also to the survey of 90Sr hyperaccumulation plants.Seven desert plants, phragmites autstralis, lycium ruthenicum, hexinia polydichotoma,halogeton glomeratus, tamarix hispida., calligonum mongolicum and halocnermum strobilaceum, which from a contaminated site were collected, and the specific activities of 90Sr in these plants were determined. The influence factors such as plant species, tissue, live stages were studied. The plants are slightly contaminated by 90Sr with the average specific activity of (3.6±4.3) mBq/g, which depend on plant species, live stages and variational in different tissue. The specific activity of 90Sr in these desert plant is decreased as halogeton glomeratus＞hexinia polydichotoma ＞ lycium ruthenicum ＞ tamarix hispida ＞ phragmites autstralis ＞calligonum mongolicum ＞ halocnermum strobilaceum. The specific activity of a (90Sr) in growing plants is higher than that in grown ones. For the different tissues of phragmites autstralis, a(90 Sr) decreases in the sequency of roots＞leaves≈tassels＞stems. The specific activity of 90Sr in plants analysed as fetched is higher than that had been rinsed, that means resuspension is the main source of the contamination.%为评估沙漠植物受90Sr污染状况,寻找∞sr超积累植物,研究了沙漠植物中90Sr的含量及分布.通过采集放射性污染区内的植物,分析其90Sr含量,研究了生长在某污染场地的芦苇、黑果枸杞、河西苣、盐生草、刚毛柽柳、沙拐枣、盐节木等7种沙漠植物中90Sr的含量及其与植物种类、部位和生长周期的关系.结果表明,所研究沙漠植物受90Sr污染但不严重,7种沙漠植物体内90Sr的比活度为(3.6±4.3)mBq/g(干重).沙漠植物中90Sr的含量与植物种类、生长发育期关系密切,且因部位而异.7种沙漠植物中90Sr的比活度大小顺序为:盐生草>河西苣>黑果枸杞>别毛柽柳>芦苇>沙拐枣>盐节木;植物生长期采集样品中90Sr的比活度更高;芦苇各部位中90Sr比活度大小依次为根>穗≈叶>茎.未清洗芦苇样品中90Sr的含量比清洗干净的芦苇样品中的含量高得多,表明再悬浮是植物受污染的主要原因.
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