Wu Songlin, Liu Yunjia, Southam Gordon, Nguyen Tuan A H, Konhauser Kurt O, You Fang, Bougoure Jeremy J, Paterson David, Chan Ting-Shan, Lu Ying-Rui, Haw Shu-Chih, Yi Qing, Li Zhen, Robertson Lachlan M, Hall Merinda, Saha Narottam, Ok Yong Sik, Huang Longbin
Centre for Mined Land Rehabilitation, Sustainable Minerals Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
School of Earth & Environmental Sciences, The University of Queensland, Brisbane, QLD 4072, Australia.
iScience. 2023 Jun 24;26(7):107102. doi: 10.1016/j.isci.2023.107102. eCollection 2023 Jul 21.
Ecological engineering of soil formation in tailings is an emerging technology toward sustainable rehabilitation of iron (Fe) ore tailings landscapes worldwide, which requires the formation of well-organized and stable soil aggregates in finely textured tailings. Here, we demonstrate an approach using microbial and rhizosphere processes to progressively drive aggregate formation and development in Fe ore tailings. The aggregates were initially formed through the agglomeration of mineral particles by organic cements derived from microbial decomposition of exogenous organic matter. The aggregate stability was consolidated by colloidal nanosized Fe(III)-Si minerals formed during Fe-bearing primary mineral weathering driven by rhizosphere biogeochemical processes of pioneer plants. From these findings, we proposed a conceptual model for progressive aggregate structure development in the tailings with Fe(III)-Si rich cements as core nuclei. This renewable resource dependent eco-engineering approach opens a sustainable pathway to achieve resilient tailings rehabilitation without resorting to excavating natural soil resources.
尾矿土壤形成的生态工程是一项新兴技术，旨在实现全球铁矿石尾矿景观的可持续恢复，这需要在质地细腻的尾矿中形成组织良好且稳定的土壤团聚体。在此，我们展示了一种利用微生物和根际过程逐步推动铁矿石尾矿团聚体形成和发育的方法。团聚体最初是通过外源有机物微生物分解产生的有机胶结物使矿物颗粒团聚而形成的。由先锋植物根际生物地球化学过程驱动的含铁原生矿物风化过程中形成的胶体纳米级铁（III）-硅矿物巩固了团聚体的稳定性。基于这些发现，我们提出了一个以富含铁（III）-硅的胶结物为核心核的尾矿团聚体结构渐进发育的概念模型。这种依赖可再生资源的生态工程方法开辟了一条可持续途径，无需挖掘天然土壤资源就能实现尾矿的韧性恢复。
