Abstract：
Floating treatment wetlands (FTW) are receiving growing interest as a phyto-technology. However, there are significant research gaps regarding the actual role of plant species and plant-microbiome interactions. In this study, the nutrient uptake of Equisetum hyemale was examined in FTW microcosms under the influence of abiotic stressors: As (3 mg/L) and Pb (3 mg/L) as well as Cl- (300 and 800 mg/L) in reference to a control during a short screening experiment. High removal efficiency of nutrients in water solutions, up to 88 % for TN and 93 % for PO4-P, was observed. However, PO4-P removal was inhibited in the As reactor, with a maximum efficiency of only 11 %. Lead and As were removed with high efficiency, reaching 98 % and 79 % respectively. At the same time only Pb was effectively bound to root biomass, reaching up to 51 %. Limited As accumulation of 0.5 % in plant roots suggests that microbial processes play a major role in its reduction. The development and structure of microbiome in the microcosms was analysed by means of 16S rRNA gene amplicon sequencing, proving that Pb was the most influential factor in terms of selection pressure on specified bacterial groups. In the As treatment, the emergence of a Serratia subpopulation was observed, while the Cl- treatment preserved a rhizobiome composition most closely resembling the control. This study indicates that E. hyemale is a suitable species for use in FTWs treating Pb polluted water that at the same time is capable to withstand periodic increases in salinity. E. hyemale exhibits low As binding in biomass; however, extended exposure might amplify this effect because of the slow-acting, but beneficial, mechanism of As uptake by roots and shoots. Microbiome analysis complements insights into mechanisms of FTW performance and impact of stress factors on bacterial structure and functions.
摘要：
漂浮处理湿地（FTW）作为一种植物技术受到越来越多的关注，然而,关于植物物种和植物-微生物组相互作用的实际作用存在显著的研究空白。在这项研究中,在FTW微观世界中，在非生物应激源的影响下检查了木贼的养分吸收性能：As（3mg/L）和Pb（3mg/L）以及Cl-（300和800mg/L）在短期筛选实验中参考对照。对水溶液中营养物质的去除效率高，观察到TN高达88%，PO4-P高达93%。然而,As反应器中PO4-P的去除受到抑制，最大值为11%。高效去除铅和砷，分别达到98%和79%。同时，只有Pb有效地结合在根生物量中（达到51％）。植物根中0.5％的积累有限，表明微生物过程在其减少中起主要作用。通过16SrRNA基因扩增子测序分析了微观世界中微生物组的发育和结构，证明Pb是对特定细菌群的选择压力影响最大的因素。反过来,随着沙雷氏菌亚群的治疗发展，而Cl-处理导致根瘤菌组成与对照最相似。这项研究的结果表明，E.hyemale是在Pb污染水体中使用FTW的合适物种，同时能够承受周期性的盐度增加。E.hyemale在生物质中表现出低的As结合；然而，长期暴露可能会放大这种影响，因为作用缓慢，但有益的，根和芽吸收砷的机制。微生物组分析补充了对FTW性能机制以及所施加的应激因子对细菌结构和功能的影响的见解。
