Belowground-Aboveground climate allies: arbuscular mycorrhizal fungi as ecosystem bridges for greenhouse gas mitigation.

Climate change, fuelled by rising greenhouse gas (GHG) emissions, threatens ecosystems and global food security, necessitating innovative nature-based solutions. Arbuscular mycorrhizal fungi (AMF), an ancient underground symbiosis, emerge as potent climate allies with the capacity to mitigate GHG emissions and enhance ecosystem resilience. By promoting root-derived carbon inputs, stabilizing soil aggregates, and producing glomalin, AMF enhance soil carbon sequestration, contributing to long-term soil organic matter storage. In wetland and rice systems, they influence methane dynamics by suppressing methanogenesis and stimulating methanotrophy. Their pivotal role in nitrogen cycling—improving plant N uptake efficiency and modulating nitrifier–denitrifier communities—helps lower nitrous oxide emissions, linking below-ground processes to above-ground climate benefits. Evidence across ecosystems shows that AMF-mediated functions are context-dependent and are influenced not only by agricultural management practices but also by broader anthropogenic activities (e.g., land-use change, fertilizer application, pollution) and climatic factors (e.g., temperature, precipitation, drought), yet they can be strengthened through sustainable management practices, including reduced tillage, cover cropping, and targeted inoculation. Recent molecular and omics-based insights, encompassing genomics, transcriptomics, and synthetic consortia approaches, provide mechanistic understanding and strategies to harness AMF for climate-smart agriculture. Despite their promise, methodological constraints, environmental variability, and limited long-term field studies have restricted their integration into policy and carbon accounting frameworks. Developing standardized indicators, ecosystem-specific models, and precision deployment strategies will be critical to scale AMF’s climate impact. Leveraging these underground allies can reduce GHG emissions, improve soil health, and support sustainable agricultural intensification, bridging below-ground symbioses with above-ground climate mitigation and global sustainability goals.