Chu Shu-Yi, Jing Chuang-Xin, Zhang Xia-Ying, Huang Zhi-da, Xiao Ji-Bo
Wenzhou Academy of Agricultural Sciences, Wenzhou 325006, Zhejiang, China.
College of Life and Environmental Science, Wenzhou University, Wenzhou 325035, Zhejiang, China.
Ying Yong Sheng Tai Xue Bao. 2020 Feb;31(2):608-614. doi: 10.13287/j.1001-9332.202002.025.
To solve the yellow colorization in water caused by iron ion, we evaluated the remediation performances of six aquatic plant species (Hygroryza aristata, Myriophyllum verticillatum, Hydrocotyle verticillata, Jussiaea stipulacea, Pistia stratiotes and Rotala rotundifolia) using hydroponic experiment. Effects of iron concentration, pH, plant biomass on iron removal were investigated, and the intensification of removing iron incurred by aeration was also discussed. Results showed that all the examined plant species could improve both divalent iron and total iron removal, but with significant difference in their performance. Divalent iron concentrations were decreased by H. aristata and H. verticillata from 5.0 mg·L to 0.23 and 0.26 mg·L within 24 h, respectively, meeting the standard of supplementary items for the drinking water and surface water sources (divalent iron concentration ≤0.3 mg·L), while total iron concentrations declined to 0.84 and 1.21 mg·L with removal efficiency of 83.2% and 75.8%, respectively. Concentrations of divalent iron and total iron of plant treatment plots at pH 5, 6, 7, 8 were not significantly different, with removal efficiency of divalent iron and total iron being among 95.4%-98.4% and 92.2%-94.6%, separately. When initial divalent iron concentration was less than 5.0 mg·L, removal efficiency of divalent iron and total iron increased with the increases of divalent iron concentration. The growth of H. aristata was inhibited at divalent iron concentration of 10.0 mg·L. Total iron removal was not stable during the trial. Removal efficiency of plant treatment rose only by 7.0% compared with the control, which was much lower than other concentration treatments. The divalent iron concentration was decreased to ＜ 0.3 mg·L in 24 h at plant biomass :300 g, with no difference of removal efficiency among biomass treatments. Both intermittent and continuous aeration enhanced iron removal by H. aristata, but continuous aeration was more favorable for the removal of total iron due to stabilization.
为解决铁离子导致的水体发黄问题，我们通过水培实验评估了六种水生植物（尖叶水蓑衣、狐尾藻、铜钱草、黄花水龙、大薸和轮叶黑藻）的修复性能。研究了铁浓度、pH值、植物生物量对铁去除的影响，并探讨了曝气对强化铁去除的作用。结果表明，所有受试植物均能提高二价铁和总铁的去除率，但其性能存在显著差异。尖叶水蓑衣和铜钱草在24小时内分别将二价铁浓度从5.0毫克/升降至0.23毫克/升和0.26毫克/升，符合饮用水和地表水水源补充项目标准（二价铁浓度≤0.3毫克/升），而总铁浓度分别降至0.84毫克/升和1.21毫克/升，去除效率分别为83.2%和75.8%。pH值为5、6、7、8时，植物处理区的二价铁和总铁浓度无显著差异，二价铁和总铁的去除效率分别在95.4%-98.4%和92.2%-94.6%之间。当初始二价铁浓度小于5.0毫克/升时，二价铁和总铁的去除效率随二价铁浓度的增加而提高。二价铁浓度为10.0毫克/升时，尖叶水蓑衣的生长受到抑制。试验期间总铁去除不稳定。与对照相比，植物处理的去除效率仅提高了7.0%，远低于其他浓度处理。植物生物量为300克时，二价铁浓度在24小时内降至＜0.3毫克/升，生物量处理之间的去除效率无差异。间歇曝气和连续曝气均能提高尖叶水蓑衣对铁的去除率，但连续曝气由于更稳定，对总铁的去除更有利。
