铀及其伴生重金属镉的根茎类富集植物的筛选

为研究植物对铀(U)、镉(Cd)的富集特性,在每千克土中分别外源添加铀、镉150 mg和15 mg,试验评价5科8种根茎类植物的污染耐受性和铀、镉富集转运效应,筛选富集植物,并以对铀有良好富集效果的植物向日葵作为对照,通过主成分分析对植物铀、镉富集转运能力进行综合评价。结果表明:8种植物中,雪莲果综合评价最高,各部生物量均大于对照,单株铀积累量和铀、镉积累总量均最大,分别为3 564.75μg和4 342.95μg,根部铀含量为638.89 mg·kg~(-1)DW,铀富集系数4.26;此外,由于雪莲果有膨大的块状茎,生物量较大,存在用于植物修复的潜质。苤蓝吸收铀、镉最少,单株铀、镉含量分别低至1.45 mg·kg~(-1)DW和11.45 mg·kg~(-1)DW,贮藏部位的铀、镉含量更低,分别仅有1.43 mg·kg-1DW和2.43 mg·kg~(-1)DW,故苤蓝有应用于污染土再利用的潜质。

Screening of rhizomatic accumulators to uranium and cadmium

To study plants uranium(U)and cadmium(Cd)enrichment characteristics is significance. The U-Cd-contaminated soil was con-ducted to study the tolerance,accumulation and transformation of U and Cd using eight rhizomatic plants(Saussurea involucrata, Colocasia esculenta L., Acorus calamus L., Alocasia macrorrhiza L., Ipomoea batatas, Dioscorea Transversa, Solanum tuberosum, Brassica oleracea var. caulorapa, Helianthus annuus)under the additional 150 mg·kg-1 U,15 mg·kg-1 Cd;The sunflower worked as CK. The advantage of e-valuation method was used to synthesized comment these plants. Results was showed that the roots of the implemented plants are the main parts to store the U and Cd;the translocation factor from the underground part to the storage is lower than the factor from the storage to up-ground part;the synthesized comment of Saussurea involucrata, with the best tolerance and stronger capability in extracting and accumulat-ing U and Cd, is the highest among the eight species of plants. The U content in underground part and the bioaccumulation factor of Saus-surea involucrata are up to 638.89 mg·kg-1 DW and 4.26, respectively. Moreover, the single U bioaccumulation quantity and the total U and Cd bioaccumulation quantity of Saussurea involucrata are also highest up to 3 564.75μg and 4 342.95μg, respectively. On the contrary, the Brassica oleracea var. caulorapa perform worst in this experiment, whose U and Cd contents are down to 1.45 mg·kg-1 DW和11.45 mg·kg-1 DW, respectively. The Brassica oleracea var. caulorapa has the ability to recycle the contaminated soil.