02147nas a2200205   4500008004100000245009900041210006900140260005900209300000800268490000900276520148500285653001501770653001601785653001401801653001801815653001701833100002201850700002101872856004801893       2024                        eng d00aDevelopment of a laboratory simulation for freeze-thaw of aeolian sediments in glacial systems0 aDevelopment of a laboratory simulation for freezethaw of aeolian  aBoulder, CO, USAbUniversity of Colorado Boulderc2024  a2610 vM.A.3 a<p>Glacial systems are vital for supplying trace metals, nutrients, and weathering products to downstream ecosystems. While subglacial and proglacial weathering pathways are highly studied, supraglacial weathering processes receive less attention. Aeolian sediments on glaciers can lower albedo, generating meltwater; this water can refreeze around sediment grains during cloudy periods or when the sun is obstructed, resulting in a freeze-thaw process. For solute generation in the most upstream source in glacial-proglacial environments, it&#39;s unclear whether chemical or physical weathering dominates nutrient release. This study presents a methodology to simulate freeze-thaw processes in a controlled laboratory setting to understand the importance of freeze-thaw in nutrient mobilization. Analysis of sediments from Antarctica&#39;s McMurdo Dry Valleys showed significant differences in the concentrations of ion, nutrient, and trace metal between initial wetting and subsequent freeze-thaw cycles. For example, phosphorus concentrations consistently increased with each cycle, indicating that freeze-thaw is an important mobilization mechanism for this nutrient. Silicon increased from cycle 1-30 but decreased at cycle 60 and iron concentrations were initially higher but decreased during subsequent cycles. This research highlights the importance of freeze-thaw processes in understanding glacial weathering dynamics and nutrient release for downstream ecosystems.</p>10aAntarctica10afreeze-thaw10anutrients10aTaylor Valley10atrace metals1 aMondragon, Denise1 aDiaz, Melisa, A.  uhttps://www.proquest.com/docview/3066792202