Characterizing snow relict assemblages of soil arthropods at risk of disappearing due to climate change

Climate change is reducing snow cover and duration in montane regions, threatening snow-dependent ecosystems, yet how soil arthropods respond to altered snow regimes in montane regions remains unclear. This study investigates soil arthropod and vegetation assemblages in late-lying snowbed habitats and adjacent alpine heath at ∼950 m elevation in the Cairngorms National Park, Scotland. Using paired transects, we compared plant and soil arthropod communities as well as functional adapations of specimens across habitats. As expected snowbeds exhibited higher soil moisture, fewer freeze-thaw cycles, and distinct graminoid-dominated vegetation compared to closely located hillslope. While overall arthropod community composition did not differ significantly between habitats, abundance of Acari and Collembola and some functional groups were greater in the adjacent hillslope, whilst Acari mites were negatively associated with soil moisture. These findings suggest that environmental filtering shapes arthropod communities at fine ecological scales. As snowbed habitats decline under climate change, trait-based monitoring may be critical for detecting subtle shifts in soil biodiversity and ecosystem function.