Bioscience Evidence 2024, Vol.14, No.4, 161-171 http://bioscipublisher.com/index.php/be 164 deep soil freezing, which is crucial for maintaining soil moisture during winter and early spring (Sanders-DeMott et al., 2019; Wilson et al., 2020). In the sagebrush steppe, declining snowpack has been shown to reduce soil respiration and moisture, potentially altering the carbon cycle and vegetation cover (Tucker et al., 2016). Similarly, in alpine and arctic ecosystems, snowpack depth influences the timing of snowmelt, which affects soil water availability and the length of the growing season for vegetation (Harpold et al., 2016; Rixen et al., 2022). 4.2 Habitat provision for flora and fauna Snowpack provides essential habitat for various flora and fauna, particularly in cold biomes. It creates a stable microclimate that protects plants and animals from extreme temperatures and desiccation. For example, in tundra ecosystems, snow cover determines ground temperature and moisture availability, which are critical for plant-animal interactions and microbial processes (Rixen et al., 2022). Additionally, snowpack influences the distribution and abundance of vegetation, which in turn affects habitat availability for wildlife. In the sagebrush steppe, changes in snowpack depth can alter vegetation cover, impacting habitat quality for species dependent on this ecosystem (Tucker et al., 2016). 4.3 Role in nutrient cycling and soil health Snowpack significantly impacts nutrient cycling and soil health by modulating soil temperature and moisture, which influence microbial activity and nutrient availability. Reduced snowpack can lead to increased soil freezing, which affects soil respiration and nutrient leaching. For instance, in an alpine fir forest, snowpack reduction was found to stimulate soil nutrient leaching without significantly changing microbial biomass, indicating that soil microbes can rapidly adapt to changes in snowpack (Yang et al., 2021). In subalpine grasslands, variations in snow depth were shown to modify nitrogen-related microbial abundances and activities, affecting nutrient dynamics and soil health (Jusselme et al., 2016). Additionally, snowpack influences litter decomposition and elemental cycling, with thicker snowpacks maintaining more stable nutrient levels in forest ecosystems (Chen et al., 2018). 4.4 Case studies on ecosystem dependencies on snowpack Several case studies highlight the dependencies of ecosystems on snowpack. At the Hubbard Brook Experimental Forest, long-term studies have shown that snowpack dynamics influence soil microclimate and ecosystem function, with implications for carbon and nitrogen cycling processes (Sanders‐DeMott et al., 2019; Wilson et al., 2020). In the sagebrush steppe, snowpack manipulation experiments using snowfences demonstrated that snow depth affects soil respiration and vegetation cover, with potential impacts on the regional carbon balance (Tucker et al., 2016). In the French Alps, historical agricultural practices created terraces with varying snow depths, providing a natural experiment to study the effects of snowpack on soil microbial functioning and nutrient dynamics (Jusselme et al., 2016). These case studies underscore the importance of snowpack in maintaining ecosystem health and resilience in the face of climate change. 5 Snowpack and Climate Change 5.1 Effects of climate change on snowpack dynamics Climate change significantly impacts snowpack dynamics by altering surface air temperatures (SAT) and precipitation patterns. Increased SAT leads to fewer sub-zero days, reduced snowfall, and more frequent rain-on-snow events, which collectively decrease snowpack accumulation and snow water equivalent (SWE) (Irannezhad et al., 2022). These changes result in earlier snowmelt and reduced springtime freshwater availability, particularly in cold climate regions (Irannezhad et al., 2022). Additionally, variations in snow depth and duration influence soil temperatures, leading to colder and more variable winter soil conditions, which have important implications for ecosystem function (Sanders-DeMott et al., 2019; Wilson et al., 2020). 5.2 Projected changes in snowpack patterns Future projections indicate a substantial reduction in snow cover area, particularly in alpine systems. For instance, in the Sierra Nevada mountain range, snow cover is expected to decrease by an average of 60.4% by the end of the century (Collados-Lara et al., 2019). Similarly, in the Blue Mountains of Oregon, snow-dominated watersheds are
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