Contrasting Export of Iron and Manganese between High Arctic and Sub-Arctic Glacierized Watersheds

Rapid warming in polar and alpine regions is accelerating glacier retreat, producing vast quantities of meltwater and sediments that are delivered to downstream ecosystems. Glacial meltwaters contain essential micronutrients, such as iron (Fe) and manganese (Mn), which may stimulate primary production in freshwater and marine ecosystems, potentially influencing carbon cycling. While dissolved Fe and Mn cycling are relatively well studied, the role of sediment-bound species remains poorly constrained despite their high potential bioavailability.Here we present data on sediment-bound and dissolved Fe and Mn concentrations and flux, and associated chemical weathering processes, along source-to-sink transects in glacierized catchments of the High Arctic (Svalbard Archipelago) and Sub-Arctic regions (Jostedalsbreen ice cap and Jotunheimen mountain range, Norway). We analyzed meltwaters from 20 glacierized catchments spanning diverse lithologies with glacial coverage ranging from 3% to 62%, including metamorphic, sedimentary, carbonate, and plutonic substrates. Dissolved trace elements (