两种有机酸对铀和^(241)Am污染土壤植物修复影响的比较研究  

Effect of the two organic acids on the phytoremediation of the soil contaminated by uranium and ^(241)Am

作　　者：王萍[1] 杜良[1] 苏容波[1] 谭昭怡[1] 李涛文[1] 郭洪波[1] 张东[1] WANG Ping DU Liang SU Rong-bo TAN Zhao-yi LI Tao-wen GUO Hong-bo ZHANG Dong(Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, Sichuan, China)

机构地区：[1]中国工程物理研究院核物理与化学研究所,四川绵阳621900

出　　处：《安全与环境学报》2016年第6期287-291,共5页Journal of Safety and Environment

基　　金：国家自然科学基金项目(21577133)

摘　　要：为了实现放射性核素污染土壤植物修复的工程化应用,在前期植物筛选的基础上,选取对铀富集能力较强的芥菜和对^(241)Am富集能力较强的大麦进行盆栽试验,研究不同含量的柠檬酸和苹果酸对铀、^(241)Am污染土壤植物修复效果的影响。从转移系数(TFs)、富集系数(BFs)、盆栽植物生物量及提取效率等方面对有机酸作用下两种核素的去除效果进行了研究。结果表明,与柠檬酸相比,苹果酸也能促进植物对土壤中铀和^(241)Am的吸收,并能促进铀和^(241)Am在植物体内的运输,但其促进能力较弱。在相同的土壤条件下,芥菜地上部的铀富集系数高于大麦地上部的^(241)Am富集系数,铀在植物体内的转移系数也远高于^(241)Am,表明在试验给定的条件下,铀比^(241)Am更容易在植物体内运输迁移。当有机酸含量在20 mmol/kg及以上时,盆栽植物的生物量大大降低,降低幅度在20%以上,表明土壤中有机酸含量太高会严重影响植物的正常生长发育。在环境条件相同的情况下,盆栽芥菜的铀提取率远高于盆栽大麦的^(241)Am提取率。The paper is inclined to make an investigation of the effects of the two organic acids on the phytoremediation of the soil contaminated by uranium and 241Am by choosing mustard and barley as the bioaccumulation factor （BFs）, transfer factor （TFs）, and the biomass of the pot-grown plants. To investigate the effects of the citric acid and malic acid concentrations on the phytoremediation of the soil contaminated by U and 241 Am, it is necessary to add up citric acid （CA） and malie acid （MA） at different concentrations so as to make the concentration of CA up to 0, 5 mmol/kg, 10 mmol/kg, 20 mmol/kg and 30 mmol/kg and MA to 0, 5 mmol/kg, 10 mmol/kg and 20 mmol/kg, respectively. CA and MA were added one week before the plants were harvested. When the plants were harvested after growing for 55 d, it is necessary to compare the phytoextraction effects of U and 24J Am, test the biomass of the different parts of the crops and measure the concentrations of U and 241 Am with a portable γ spectrometer. The results indicate that, the BFs of U and 241 Am on the upper parts of the plants should be taken in the following descending order： CA- U 〉 MA - U 〉 CA _241 Am 〉 MA _241 Am, and CA - 241 Am 〉 MA _241 Am 〉 CA - U 〉 MA - U to roots at 20 mmol/kg organic acid in the soil. Malic acid tends to promote the absorption of U and 24J Am of the plant roots, and so does it promote the transfer of U and 241 Am in the plants, though its function for promotion turns to be a bit weaker than that of citric acid. Under the same soil conditions, U BFs of the mustard＇s upper parts proves to be higher than that of 241 Am BFs to harley＇s whereas TFs of U proves higher than that of 241 Am, too. This may attribute to easier Lransfer of U in the plants than 241 Am in our experiment. Moreover, when the concentration of organic acids is higher than 20μmol/kg, the biomass of the potted plants would be greatly reduced to lower than by 20 percent, which probably indicates that the growth of the plant is likely to be s

关 键 词：环境工程学 植物修复 241Am 铀 有机酸 

分 类 号：X53[环境科学与工程—环境工程]