Fig. 1: Proposed roadmap for aligning mercury (Hg) mitigation with climate action through the microbe-mediated Hg-microbe-GHG nexus. Modern Hg inputs (light red arrows) continuously deposit into ecosystems and convert to legacy Hg pools via aging (gray dashed arrow).

Legacy Hg can be remobilized (gray solid arrow) by environmental disturbances. Both modern and remobilized legacy Hg impact microbial communities (see details in Box 2). Global Hg mitigation efforts (red arrow) substantially alter modern Hg inputs, potentially cascading through microbial communities to influence their greenhouse gas (GHG) emissions and thus climate change (blue arrow). Unlike the established climate feedback on microbes and Hg cycling (black arrow), ecosystem sensitivity to Hg mitigation—and its cascading GHG effects—remains poorly constrained. Therefore, we propose a three-step roadmap, aiming to identify these Hg mitigation-sensitive ecosystems and help align Hg mitigation with climate action.