Luo Jie, Cai Limei, Qi Shihua, Wu Jian, Gu Xiaowen Sophie
College of Resources and Environment, Yangtze University, 111 University Road, Wuhan, China; China University of Geosciences, 388 Lumo Road, Wuhan, 430074, China.
College of Resources and Environment, Yangtze University, 111 University Road, Wuhan, China.
Chemosphere. 2018 Feb;193:244-250. doi: 10.1016/j.chemosphere.2017.11.024. Epub 2017 Nov 7.
The phytoremediation efficiency of various metals by Ficus microcarpa was evaluated through a real scale experiment in the present study. The root biomass production of the species varied significantly from 3.68 to 5.43 g because of the spatial heterogeneity of different metals. It would take 4-93 years to purify the excess Cd of the experimental site. Mercury was the most inflexible element which can barely be phytoremediated by F. microcarpa. After the species transplanted from the polluted soil to the clean site, Cd and Cu were transferred to the rhizosphere soil to different extent while the bulk soil was barely influenced. Relative to Cd and Cu, significantly fewer amounts of Pb and Hg were released. The highest concentrations of Cd, Cu, Hg and Pb in the clean soil were far below their corresponding safe thresholds for agricultural land after 3 months of the polluted plants were cultivated and metal concentrations of plant leaves were negligible, both indicated the low ecological risk of transplantation. Results from this study suggested a feasible disposal method for metal rich plants after phytoremediation.
在本研究中，通过实际规模的实验评估了小叶榕对各种金属的植物修复效率。由于不同金属的空间异质性，该物种的根生物量产量在3.68至5.43克之间存在显著差异。净化实验场地中过量的镉需要4至93年。汞是最难处理的元素，小叶榕几乎无法对其进行植物修复。该物种从污染土壤移植到清洁场地后，镉和铜不同程度地转移到根际土壤中，而对大块土壤几乎没有影响。相对于镉和铜，铅和汞的释放量明显较少。在种植污染植物3个月后，清洁土壤中镉、铜、汞和铅的最高浓度远低于相应的农田安全阈值，且植物叶片中的金属浓度可忽略不计，这两者均表明移植的生态风险较低。本研究结果为植物修复后富金属植物的可行处置方法提供了依据。
