Li Chang-wu, Hu Nan, Ding De-xin, Hu Jin-song, Li Guang-yue, Wang Yong-dong
Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, 28 West Changsheng Road, Hengyang, Hunan, 421001, People's Republic of China.
Environ Sci Pollut Res Int. 2015 Apr;22(8):6155-63. doi: 10.1007/s11356-014-3803-x. Epub 2014 Nov 18.
This is the first report on using Macleaya cordata for phytoextraction of uranium from the uranium contaminated soil in the greenhouse. Macleaya M. cordata was found to increase uranium concentration in the soil solution by increasing the dissolved organic carbon (DOC). The amendment experiments with citric acid (CA) and [S,S]-ethylenediamine disuccinic acid (EDDS) at the rates of 1.0, 2.5, 5.0, and 10.0 mmol kg(-1) dry weight (DW) soil showed that EDDS was more efficient to increase uranium concentration in the shoot than CA when they were applied at the same rate. The applications of 5.0 mmol kg(-1) EDDS and 10.0 mmol kg(-1) CA were most appropriate for increasing uranium concentrations in the shoot of M. cordata. CA was more efficient to increase the solubility of uranium at the same application rates except for 2.5 mmol kg(-1) application rate. There was a linear correlation between the uranium concentration in the shoot and the average uranium concentration of one planted pot during 14 days in soil solution after the application of different rates of EDDS and CA, respectively (r(2) = 0.972, P < 0.01; r (2) = 0.948, P < 0.01), indicating that uranium uptake was dependent on the soluble uranium concentration. The Fe-U-DOC and Mn-U-DOC complexes were probably formed after the application of CA. Soil solution pH and Fe, Mn, Ca, and DOC concentrations in soil solution were found to be changed by the chelates.
这是关于在温室中利用博落回对铀污染土壤进行植物提取的首份报告。研究发现，博落回可通过增加溶解有机碳（DOC）来提高土壤溶液中的铀浓度。以1.0、2.5、5.0和10.0 mmol kg(-1)干重（DW）土壤的用量对柠檬酸（CA）和[S,S]-乙二胺二琥珀酸（EDDS）进行改良实验，结果表明，当以相同用量施用时，EDDS在提高地上部铀浓度方面比CA更有效。施用5.0 mmol kg(-1) EDDS和10.0 mmol kg(-1) CA最适合提高博落回地上部的铀浓度。除2.5 mmol kg(-1)用量外，在相同施用率下，CA在提高铀溶解度方面更有效。分别施用不同用量的EDDS和CA后，地上部铀浓度与一个种植盆在14天内土壤溶液中平均铀浓度之间存在线性相关性（r(2) = 0.972，P < 0.01；r(2) = 0.948，P < 0.01），这表明铀的吸收取决于可溶性铀浓度。施用CA后可能形成了Fe-U-DOC和Mn-U-DOC络合物。发现螯合剂会改变土壤溶液pH值以及土壤溶液中的铁、锰、钙和DOC浓度。
