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Snow is an important driver of ecosystem processes in cold biomes. Snow accumulation determines ground temperature, light conditions, and moisture availability during winter. It also affects the growing season’s start and end, and plant access to moisture and nutrients. Here, we review the current knowledge of the snow cover’s role for vegetation, plant-animal interactions, permafrost conditions, microbial processes, and biogeochemical cycling. We also compare studies of natural snow gradients with snow experimental manipulation studies to assess time scale difference of these approaches. The number of tundra snow studies has increased considerably in recent years, yet we still lack a comprehensive overview of how altered snow conditions will affect these ecosystems. Specifically, we found a mismatch in the timing of snowmelt when comparing studies of natural snow gradients with snow manipulations. We found that snowmelt timing achieved by snow addition and snow removal manipulations (average 7.9 days advance and 5.5 days delay, respectively) were substantially lower than the temporal variation over natural spatial gradients within a given year (mean range 56 days) or among years (mean range 32 days). Differences between snow study approaches need to be accounted for when projecting snow dynamics and their impact on ecosystems in future climates.

This study compared the effectiveness of SMART Board, interactive whiteboard technology and traditional flash cards in teaching reading in a small-group instructional arrangement. Three students with moderate intellectual disabilities were taught to read grocery store aisle marker words under each condition. Observational learning (students learning other group members' words) was also assessed across each condition. The effectiveness of the two procedures was evaluated using an adapted alternating-treatments design (AATD) across two conditions and replicated across students. Results indicated that both SMART Board and flash card instruction were effective in teaching target sight words. However, students read a greater percentage of observational words when words were presented using SMART Board technology.

This study compared the effectiveness of SMART Board, interactive white board technology and traditional flash cards in teaching reading in a small-group instructional arrangement. Three students with moderate intellectual disabilities were taught to read grocery store aisle marker words under each condition. Observational learning (students learning other group members' words) was also assessed across each condition. The effectiveness of the two procedures was evaluated using an adapted alternating-treatments design (AATD) across two conditions and replicated across students. Results indicated that both SMART Board and flash card instruction were effective in teaching target sight words. However, students read a greater percentage of observational words when words were presented using SMART Board technology. [ABSTRACT FROM AUTHOR]

Many animals depend on stable below‐the‐snow (subnivium) conditions to survive winter in seasonally cold regions. Freeze‐tolerant ectotherms may experience increased ice content and/or energy expenditure in suboptimal subnivium conditions, with implications for overwinter survival and body reserves available for spring reproduction. We used a novel mechanistic modeling approach to explore effects of winter climate on the microclimate conditions, energy expenditure, and ice dynamics of the freeze‐tolerant, subnivium‐dwelling wood frog (Lithobates sylvaticus) in the Upper Midwest and Great Lakes Basin region of the United States. We hypothesized that (1) frogs would experience the greatest energy cost to survive winter in southern regions of our study area, where air temperatures are warmer and shallower snow could allow for increased numbers of freeze–thaw cycles, and (2) frogs would be most vulnerable to lethal freezing in the cold, dry northwest portion of our study region. We found that total winter energy expenditure changed little with latitude because the effect of warmer soil temperatures (higher metabolic rates) to the south was offset by a shorter winter duration. Energy expenditures were greatest in the snowbelts of the Great Lakes, characterized by more persistent snow cover and relatively warm soil temperatures. In contrast, highest ice contents occurred in the northwest of the study region where air temperatures were coldest and snow was shallow. Thus, it appears that wood frogs experience a trade‐off between risk of lethal ice content and extensive use of body reserves across geographic space. Simulations showed that interpopulation differences in burrow depth and cryoprotectant concentration can influence risk of lethal ice content and overuse of body reserves prior to spring breeding, and those risks vary in relation to winter climate. Our mechanistic modeling approach is a novel tool for predicting risk and shifting niche space for cold‐adapted and subnivium‐dependent species. [ABSTRACT FROM AUTHOR]