Department of Environmental Sciences, Huazhong Agricultural University, Wuhan, China.
Int J Phytoremediation. 2012 Jan;14(1):89-99. doi: 10.1080/15226510903567471.
Arsenic is a common contaminant in soils and water. It is well established that the fern Pteris vittata L. is an As hyperaccumulator and therefore has potential to phyroremediate As-polluted soils. Also, it is accepted that rhizosphere microflora play an enhancing role in plant uptake of metallic elements from soils. Studies showed that hydroponiclly grown P. Vittata accumulated arsenite more than the arsenate form of As apparently because arsenate and phosphate are analogues and therefore its absorption is inhibited by phosphate. The objective of this study was to determine whether addition of five different arsenate-reducing bacteria would enhance arsenic uptake by P. vittata grown in arsenic polluted soils in afield experiment. Results showed that addition of the As reducing bacteria promoted the growth of P. vittata, increased As accumulation, activated soil insoluble As, and reduced As leaching compared to the untreated control. Plant biomass increased by 53% and As uptake by 44%. As leaching was reduced by 29% to 71% depending on the As reducing bacterium. The results in their entirety permitted some insight into the mechanisms by which the arsenate reducing bacteria enhanced the effectiveness of P. vittata to remove As from the polluted soil.
砷是土壤和水中的常见污染物。已经证实凤尾蕨是一种砷超积累植物，因此具有修复砷污染土壤的潜力。此外，人们普遍认为根际微生物在植物从土壤中吸收金属元素方面发挥着增强作用。研究表明，水培生长的凤尾蕨积累的亚砷酸盐多于砷酸盐形式的砷，显然是因为砷酸盐和磷酸盐是类似物，因此其吸收受到磷酸盐的抑制。本研究的目的是确定在田间试验中，添加五种不同的砷酸盐还原菌是否会增强在砷污染土壤中生长的凤尾蕨对砷的吸收。结果表明，与未处理的对照相比，添加砷还原菌促进了凤尾蕨的生长，增加了砷的积累，激活了土壤中不溶性砷，并减少了砷的淋失。植物生物量增加了 53%，砷的吸收增加了 44%。根据砷还原菌的不同，砷的淋失减少了 29%至 71%。总的来说，这些结果使我们对砷酸盐还原菌增强凤尾蕨从污染土壤中去除砷的有效性的机制有了一些了解。
