施用微量元素对菊苣修复铀污染土壤的影响

Effects of Applying Trace Elements on Chicory Remediation of Uranium Contaminated Soil

为了探究施用微量元素对植物修复铀污染土壤的影响,在0、50、100、150 mg·kg^(-1)铀污染土壤中,分别单独施用土壤背景值含量0、1倍和5倍的Mn、Zn、Cu、Mo、B,并测定菊苣实生苗和再生苗植株干重、植株铀含量和铀富集量。结果表明,在铀污染土壤中单独施用Mn、Zn、Cu、Mo、B后,降低了菊苣实生苗植株干重,也降低再生苗植株干重(Zn除外)。在50、100 mg·kg^(-1)铀污染土壤中,每千克土壤施用50 mg B,平均增加菊苣实生苗植株铀含量129.8%,平均增加菊苣实生苗植株铀积累量77.0%;在50 mg·kg^(-1)铀污染土壤中,每千克土壤施用50 mg B,增加菊苣再生苗植株铀含量80.1%,增加再生苗植株铀积累量17.87%。因此,在中低浓度铀污染土壤,施用适量的B肥,可以提高菊苣植株铀含量和铀积累量。本研究为提高铀污染土壤的植物修复效率提供了理论依据。

To study the effects of applying trace elements on phytoremediation of uranium contaminated soil,the dry weight and uranium enrichment of chicory（ Cichorium intybus L.） seedlings and reproduced seedling were measured under soil which was treated with uranium of 0,50,100,150mg·kg^-1and amended with 0,1 and 5 times of manganese（ Mn）,zinc（ Zn）,copper（ Cu）,molybdenum（ Mo） and boron（ B） respectively. The results were shown below. After applying Mn,Zn,Cu,Mo and B,dry weights of both seedlings growing on the uranium contaminated soil and reproduced seedlings（ except the Zn treatment） were lower than that of those growing on non-contaminated soil. In the contaminated soil with levels of 50 mg· kg^-1and 100mg·kg^-1uranium,the treatment with 50 mg B per kg soil averagely increased the seedlings uranium content of 129. 8% per plant, and increased the seedling uranium accumulation by 77. 0% per plant. In the contaminated soil with 50mg·kg^-1uranium,the treatment of 50 mg B per kg soil averagely increased both the uranium content and accumulation of reproduced seedlings by 80. 1% and 17. 87% per plant respectively. It is concluded that applying boron fertilizer with appropriate amount can improve phytoremediation efficiency of chicory seedlings and reproduced seedling in moderate concentration uranium contaminated soil. This study is proposed to provide scientific basis and technical measures for improving the phytoremediation efficiency of uranium contaminated soil.