Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha-Suchdol 16500, Czech Republic.
Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, Praha-Suchdol 16500, Czech Republic.
J Hazard Mater. 2022 Oct 5;439:129562. doi: 10.1016/j.jhazmat.2022.129562. Epub 2022 Jul 8.
Arbuscular mycorrhizal fungi (AMF) exhibit great potential in heavy-metal immobilization in semi-aquatic habitats. Under high heavy-metal stress, however, the role of AMF is limited, and the detoxification mechanism of AMF in heavy metals' stabilization remains unclear. This study investigated the effects of AMF on a wetland plant (Iris pseudacorus) and chromium (Cr) immobilization at different water depths in semi-aquatic habitats with biochar addition. Results showed that AMF increased the physiological and photosynthetic functions in I. pseudacorus under Cr exposures. Besides, AMF alleviated the accumulation of reactive oxygen species and lipid peroxidation by enhancing the antioxidant enzyme activities. AMF and biochar significantly decreased Cr concentrations in outlet water and increased Cr accumulation in I. pseudacorus. Besides, biochar also vastly improved Cr accumulation in the substrate under the fluctuating water depth. AMF reduced Cr bioavailability in the substrate, with Cr (Ⅵ) concentrations and acid-soluble forms of Cr decreased by 0.3-64.5% and 19.0-40.8%, respectively. Micro-proton-induced X-ray emission was used to determine element localization and revealed that AMF improved the nutrients uptake by wetland plants and inhibited Cr translocation from roots to shoots. Overall, this study demonstrated that the interaction between AMF and biochar could significantly enhance the immobilization of high Cr concentrations in semi-aquatic habitats.
丛枝菌根真菌（AMF）在半水生生境中固定重金属方面具有很大的潜力。然而，在高重金属胁迫下，AMF 的作用有限，AMF 对重金属稳定的解毒机制仍不清楚。本研究调查了 AMF 在生物炭添加的半水生栖息地中不同水深对湿地植物（鸢尾）和铬（Cr）固定的影响。结果表明，AMF 增强了 Cr 暴露下鸢尾的生理和光合功能。此外，AMF 通过增强抗氧化酶活性缓解了活性氧和脂质过氧化的积累。AMF 和生物炭显著降低了出水中的 Cr 浓度并增加了鸢尾中的 Cr 积累。此外，生物炭还大大提高了波动水深下基质中的 Cr 积累。AMF 降低了基质中的 Cr 生物利用度，Cr（Ⅵ）浓度和酸可溶态 Cr 分别降低了 0.3-64.5%和 19.0-40.8%。微质子诱导 X 射线发射用于确定元素定位，并表明 AMF 改善了湿地植物对养分的吸收，并抑制了 Cr 从根部向地上部的转运。总的来说，本研究表明 AMF 和生物炭的相互作用可以显著增强半水生生境中高浓度 Cr 的固定。
