一种新的锶超积累植物——串叶草

目的]筛选适合污染区生长的超积累植物。方法]采用野外采样法,以国内某核设施退役厂放射性污染区域为研究对象,测定了该区优势植物(共9科17种)和土壤中的~(137)Cs、~(90)Sr放射性含量,并进行了筛选与田间修复试验。结果]污染区土壤~(137)Cs和~(90)Sr放射性含量的最大值分别为5.06×10~6和3.29×10~4Bq/kg,均超过国际规定活度限值;菊科串叶草对~(137)Cs的富集和转移系数均小于1.00,而对~(90)Sr的富集和转移系数分别是3.25和2.95,均大于1.00;串叶草具备~(90)Sr超积累植物特征且能修复土壤中5.9%的~(90)Sr,可推荐串叶草对~(90)Sr的污染土壤进行修复处理。结论]首次发现并证实菊科串叶草是一种~(90)Sr超积累植物,为开展污染区域修复治理工作提供参考。

Silphium perfoliatum:A New Hygrophyte with Strontium Hyperaccumulator Properties

Objective] The aim was to screen out hygrophyte with hyperaccumulator properties which could grow in pollution area.Method] The field sampling method was adopted.On the basis of a nuclear facility decommissioning domestic factory, the content of 137Cs and 90Sr was determined in both dominant species (17 species, 9 families) and soil in polluted areas,and dominant species screening and phytoremediation tests were carried out.Result] It was demonstrate that Silphium perfoliatum was a kind of 90Sr-hyperaccumualtor, and the maximum contents of 137Cs and 90Sr were 5.06×106 Bq/kg and 3.29×104 Bq/kg respectively, which were both above the maximum values of international regulations.The screening tests indicated that the enrichment and the transfer coefficience to 137Cs of Silphium perfoliatum were both below 1.00, while the coefficience to 90Sr were 3.25 and 2.95 respectively, which were both above 1.00.Silphium perfoliatum had the characteristic of 90Sr-hyperaccumualtor and was able to remedy 5.9% of 90Sr in the soil.Conclusion] So Silphium perfoliatum can achieve the phytoremediation of contaminated soil with 90Sr, which can provide reference for the repair work of pollution area.