W. Szafer Institute of Botany Polish Academy of Sciences, Department of Ecology, Lubicz 46, PL-31512, Krakow, Poland.
Soil Protection, Institute of Terrestrial Ecosystems, Department of Environmental Systems Science, Swiss Federal Institute of Technology (ETH), 8092, Zurich, Switzerland; Rothamsted Research, North Wyke, Okehampton, Devon, EX20 2SB, United Kingdom.
Chemosphere. 2021 Dec;285:131437. doi: 10.1016/j.chemosphere.2021.131437. Epub 2021 Jul 5.
The hyperaccumulation trait allows some plant species to allocate remarkable amounts of trace metal elements (TME) to their foliage without suffering from toxicity. Utilizing hyperaccumulating plants to remediate TME contaminated sites could provide a sustainable alternative to industrial approaches. A major hurdle that currently hampers this approach is the complexity of the plant-soil relationship. To better anticipate the outcome of future phytoremediation efforts, we evaluated the potential for soil metal-bioavailability to predict TME accumulation in two non-metallicolous and two metallicolous populations of the Zn/Cd hyperaccumulator Arabidopsis halleri. We also examined the relationship between a population's habitat and its phytoextraction efficiency. Total Zn and Cd concentrations were quantified in soil and plant material, and bioavailable fractions in soil were quantified via Diffusive Gradients in Thin-films (DGT). We found that shoot TME accumulation varied independent from both total and bioavailable soil TME concentrations in metallicolous individuals. In fact, hyperaccumulation patterns appear more plant- and less soil-driven: one non-metallicolous population proved to be as efficient in accumulating Zn on non-polluted soil as the metallicolous populations in their highly contaminated environment. Our findings demonstrate that in-situ information on plant phytoextraction efficiency is indispensable to optimize site-specific phytoremediation measures. If successful, hyperaccumulating plant biomass may provide valuable source material for application in the emerging field of green chemistry.
某些植物物种具有超积累特性，能够将大量痕量金属元素（TME）分配到叶片中而不会受到毒性影响。利用超积累植物来修复 TME 污染场地，可以为工业方法提供一种可持续的替代方案。目前，阻碍这种方法的一个主要障碍是植物-土壤关系的复杂性。为了更好地预测未来植物修复工作的结果，我们评估了土壤金属生物可利用性对两种非金属富集和两种金属富集的 Arabidopsis halleri Zn/Cd 超积累植物种群中 TME 积累的预测潜力。我们还研究了种群栖息地与其植物提取效率之间的关系。我们对土壤和植物材料中的总 Zn 和 Cd 浓度进行了量化，并通过薄膜扩散梯度（DGT）对土壤中的生物有效分数进行了量化。我们发现， shoots TME 积累与金属个体中的总土壤 TME 浓度和生物有效分数无关。实际上，超积累模式似乎更多地是由植物驱动的，而不是由土壤驱动的：一个非金属富集种群在未污染的土壤上积累 Zn 的效率与高度污染环境中的金属富集种群一样高。我们的研究结果表明，关于植物植物提取效率的现场信息对于优化特定地点的植物修复措施是必不可少的。如果成功的话，超积累植物生物量可能为新兴的绿色化学领域提供有价值的应用材料。
