Mercury Biogeochemical Cycling Across Ecosystem Boundaries

Mercury (Hg) is a globally distributed contaminant whose cycling across environmental compartments influences ecosystem and human health. Within aquatic and terrestrial systems, mercury undergoes complex redox reactions and microbial transformations that control its bioavailability and toxicity. Recent advances in molecular tools, isotopic tracing, and environmental modeling have deepened our understanding of Hg methylation, demethylation, and long-range transport. However, the interplay between biogeochemical processes across ecosystem boundaries, such as wetlands, soils, streams, and the atmosphere, remains insufficiently understood. As climate change, land use pressures, and other anthropogenic activities reshape these boundaries, elucidating the coupled biogeochemical processes driving mercury transformations is critical to predicting its fate and mitigating its ecological and health impacts.

This Research Topic aims to advance an integrative understanding of mercury biogeochemical cycling, from single-compartment mechanistic approaches to integrated multiscale frameworks across ecosystem boundaries. Building on foundational work such as sediment methylation rates, soil Hg retention, and wetland hotspots, we aim to address gaps in linking mercury cycling along terrestrial, aquatic, and atmospheric continua, across food webs from soils to aquatic systems and the atmosphere. We encourage cross-disciplinary synthesis using molecular, isotopic, and modelling tools to quantify the controls exerted by organic matter, microbes, climate variability, and land use. By bridging specific insights with holistic feedbacks between natural and human-influenced environments, this Research Topic aims to promote predictive models for Hg dynamics, bioaccumulation risk patterns, and biodiversity impacts under global environmental change.

We welcome contributions on mercury transformation, transport, and bioavailability across spatial scales, from molecular to watershed scales. Submissions may include classic single-compartment studies (e.g., methylation/demethylation in sediments, soils, or wetlands ) or integrated aquatic-terrestrial interfaces. Key themes include, but are not restricted to, microbial and geochemical processes, organic matter roles, isotopic and modeling linkages, climate and land-use effects, and ecosystem health feedback.

We welcome Original Research articles, Reviews that integrate classical literature with new data, Perspectives, and methodological advances. Field, laboratory, and modelling contributions are all encouraged, particularly those that advance mechanistic and predictive understanding of mercury cycling within an evolving environmental context.

Article types and fees

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Brief Research Report
• Data Report
• Editorial
• FAIR² Data
• Hypothesis and Theory
• Methods
• Mini Review
• Opinion
• Original Research
• ... View all formats

Articles that are accepted for publication by our external editors following rigorous peer review incur a publishing fee charged to Authors, institutions, or funders.

Article types

This Research Topic accepts the following article types, unless otherwise specified in the Research Topic description:

• Brief Research Report
• Data Report
• Editorial
• FAIR² Data
• Hypothesis and Theory
• Methods
• Mini Review
• Opinion
• Original Research
• Perspective
• Policy and Practice Reviews
• Policy Brief
• Review
• Systematic Review
• Technology and Code

Keywords: Mercury Cycling, Environmental Interfaces, Methylation and Demethylation, Ecosystem Health, Cross-Scale Biogeochemistry

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.