Yang Weidong, Liu Di, Wang Yuyan, Hussain Bilal, Zhao Fengliang, Ding Zheli, Yang Xiaoe, Zhu Zhiqiang, Dawood Muhammad
Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
Jiangxi Yangtze River Economic Zone Research Institute, Jiujiang University, Jiujiang, 332005, China.
J Environ Manage. 2021 Dec 1;299:113632. doi: 10.1016/j.jenvman.2021.113632. Epub 2021 Aug 31.
Climate-related flooding poses a potential challenge to phytoremediation of metal polluted areas. In the present study, uptake, translocation and accumulation of heavy metals (Cd, Zn and Cu), and their phytoavailability in six flood-tolerant Salix genotypes were investigated under simulated seasonal flooding conditions (non-flooding conditions were kept as the control). Plants were cultivated in a greenhouse with open windows using the soil polluted with Cd, Zn and Cu for 110 days. All the control (non-flooded) genotypes did not exhibit visible toxic symptoms, whereas the flooded genotypes showed leaf chlorosis and developed both lenticels and adventitious roots. Biomass production and metal accumulation in tissues varied with Salix genotypes. The flooded genotypes dramatically decreased aerial biomass production compared with corresponding non-flooded genotypes. All the control Salix genotypes showed relatively high accumulation for Cd, Zn and Cu in aerial parts due to high EDTA-extractable metals in the rhizosphere, exhibiting phytoextraction features. In contrast, the flooded genotypes drastically decreased uptake, translocation, accumulation, and extraction capacities for Cd, Zn and Cu in aerial parts, differing with genotypes, and tended to phyto-stabilize them in roots, especially Cu. This study indicated that flooding is a leading factor on phytoremediation efficiency for contaminated sites with willows.
与气候相关的洪水对金属污染地区的植物修复构成了潜在挑战。在本研究中，在模拟季节性洪水条件下（以非洪水条件作为对照），研究了六种耐洪柳树基因型对重金属（镉、锌和铜）的吸收、转运和积累及其植物有效性。使用被镉、锌和铜污染的土壤，在窗户开放的温室中种植植物110天。所有对照（未受洪水影响）基因型均未表现出明显的毒性症状，而受洪水影响的基因型出现叶片黄化，并形成了皮孔和不定根。不同柳树基因型的组织生物量生产和金属积累情况有所不同。与相应的未受洪水影响的基因型相比，受洪水影响的基因型地上生物量生产显著降低。由于根际中乙二胺四乙酸（EDTA）可提取的金属含量较高，所有对照柳树基因型地上部分对镉、锌和铜的积累相对较高，表现出植物提取特征。相比之下，受洪水影响的基因型地上部分对镉、锌和铜的吸收、转运、积累和提取能力大幅下降，因基因型而异，并且倾向于将它们在根部进行植物稳定，尤其是铜。本研究表明，洪水是影响柳树对污染场地植物修复效率的主要因素。
