Temporal and vertical changes in snow microbial communities during the melting season below canopy in Northern Japan

作者：Masato Ono, Kino Kobayashi, Daiki Seto, Fuki Konishi, Kaito Wada, Suzunosuke Usuba, Nozomu Takeuchi · 发表于：˜The œcryosphere · 年份：2025 · DOI：10.5194/tc-19-5983-2025 · 被引用次数：2 · 研究领域：Polar Research and Ecology、Biocrusts and Microbial Ecology、Climate change and permafrost

Abstract. During snowmelt, diverse cold-tolerant microbes thrive within snowpacks. Snow conditions in forested areas change temporally with air temperature and budburst of trees. However, their effects on relevant biological communities are not well documented. Based on periodic sampling throughout the snowmelt season (March–May 2021), this study describes the temporal and vertical changes in biological communities, including snow algae, microinvertebrates, and snow fungi, within snowpacks in Northern Japan. The melting season was divided into three periods: when the daily minimum air temperature was below the freezing point (Period A), when it was above the freezing point and before the budburst of beech trees (Period B), and after the budburst over the snow surface (Period C). During Period A, two types of algae and one of fungus were ubiquitously observed in the snowpack. During Period B, the abundance of microbes increased in the surface layer and green algal blooms visibly emerged. Later in this period, nutrients (NO3-, NH4+, and PO43-) depleted, likely inhibiting algal growth and consequently restricting the microinvertebrate population. Surface layer nutrient concentrations increased again during Period C, thereby increasing the abundance of algae and microinvertebrates. This increase in nutrients was likely due to the rainwater and tree-derived litter deposited on the snowpack. Analyses of snow pits and cores revealed that the active layers of microbes were distinct b...