Bioremediation of Metal Pollution in Freshwater Ecosystems: From Mechanisms to Ecological Recovery

Freshwater ecosystems face escalating degradation driven by the convergence of climate extremes, land-use intensification, and emerging pollutants. These stressors interact in complex ways, amplifying impacts on ecosystem structure, function, and resilience. Climate extremes, including inland flooding and drought, are becoming more frequent and severe, altering flow regimes, mobilizing pollutants and legacy contaminants, and reshaping habitat structure across river and wetland systems. Conventional restoration approaches that aim to recover historical conditions are no longer sufficient in an era of shifting baselines and non-stationary climate dynamics. A more adaptive understanding of how compound stressors interact is needed to guide freshwater management and restoration under increasingly uncertain environmental conditions.This Research Topic aims to reframe freshwater restoration as a forward-looking and adaptive process focused on sustaining ecological functions under uncertain futures, rather than recovering historical baselines. It addresses interactions among compound stressors, particularly climate extremes such as inland flooding and drought, land-use intensification, and pollutant mixtures, which are difficult to capture with conventional single-stressor approaches. Recent advances in scenario-based planning, predictive modelling, early warning monitoring, and adaptive governance offer new tools for tackling this problem. Particular attention is given to emerging and innovative approaches, including engineered microbial systems, synthetic biology, bio-inspired materials, advanced biosensors, omics-enabled monitoring, and hybrid biological-physical remediation technologies. The Topic welcomes interdisciplinary contributions integrating ecology, hydrology, environmental chemistry, modelling, and governance to diagnose degradation, develop adaptive restoration frameworks, and reimagine resilience in the face of accelerating global change.We welcome Original Research, Reviews, and Perspective articles addressing:Diagnosis of compound stressor impacts on freshwater ecosystem structure and function, including community- and ecosystem-level responsesInteractions among pollutants, other water-quality stressors, and climate extremes such as floods and droughts, including emerging contaminants such as pharmaceuticals, PFAS, microplastics, and nanomaterials, and interactions among metals and other environmental stressorsSediment–water interactions and contaminant remobilization, including environmental controls on metal speciation and bioavailabilityTrophic transfer and food-web exposure to contaminantsAdaptive, resilient restoration strategies and evaluation of restoration effectiveness under multiple stressors, including approaches supported by scenario-based planning and risk assessmentRecovery following remediation, long-term effectiveness, and risks of contaminant remobilizationComparisons of remediation and restoration performance among laboratory, mesocosm, and field settingsInnovative remediation and restoration technologies, such as engineered microbial systems, synthetic biology, bio-inspired materials, and hybrid biological-physical approachesEarly-warning indicators and continuous monitoring tools (eDNA, omics-enabled monitoring, advanced biosensors, autonomous sensors, remote sensing)Governance and social-ecological dimensions, including stakeholder co-design and Indigenous knowledgeTrade-offs and policy pathways for financing restoration at scaleCoupled hydrological-ecological-social modelling and cross-system meta-synthesesCase studies, empirical field and experimental studies, conceptual and methodological advances, and synthesis papers across freshwater systems, climates, and land uses are all encouraged.This Research Topic will address how to reduce the ecological risks of metal pollution in freshwater while avoiding new harms to organisms and habitats. It will bring together research on biological and bio-inspired methods that capture, immobilize, transform, or remove metals, and test whether these methods lower metal bioavailability and uptake by aquatic organisms. Areas of interest include microbial and probiotic approaches, algae and plants, microbial consortia, biofilms, and emerging biophotocatalytic systems. Recent advances in engineered microbes, omics, biosensors, and hybrid materials may help identify mechanisms, improve treatment performance, and monitor outcomes. Because metals cannot be destroyed, studies should distinguish removal from immobilization or changes in chemical form, and report where contaminants end up. The goal is to support safe, effective, and scalable strategies, with evidence spanning laboratory tests, mesocosms, and field settings.We welcome studies on the sources, speciation, transport, and ecological effects of cadmium, lead, arsenic, and other toxic metals in freshwater systems, alongside work testing remediation or risk-reduction methods. Themes may include probiotics and other beneficial microbes; microbial consortia and biofilms; algae, aquatic plants, and constructed wetlands; biosorption and bio-based materials; and biophotocatalytic or other hybrid treatment systems. Contributions may assess removal, immobilization, transformation, bioavailability, bioaccumulation, toxicity, non-target effects, ecosystem recovery, and treatment by-products. We encourage comparative evaluations, mechanism studies, monitoring tools, and field or community-based applications that address feasibility, scale-up, and sustainability. Relevant submissions include Original Research, Methods, Reviews, Mini Reviews, and Perspectives. Authors should state the freshwater context, target contaminant, treatment pathway, and how environmental safety and performance were measured. Topic editors: Siddhant Dash Source: https://www.frontiersin.org/research-topics/85128/bioremediation-of-metal-pollution-in-freshwater-ecosystems-from-mechanisms-to-ecological-recovery