Plant species composition in black sand extended growing season experiment, 2018 - ongoing.

As a result of climate change, the Rocky Mountain Front Range is experiencing warmer summers and earlier snowmelt. Due to the importance of snow for regulating soil temperature, growing season length, and available moisture in alpine ecosystems, even small shifts in the snow-free period could have large impacts. The focus of the Black Sand Extended Growing Season Length Experiment is to examine how terrain-related differences in climate exposure influence the way alpine habitats respond to climate change via earlier snowmelt. To simulate how climate exposure may affect plant communities, NWT LTER researchers established 5 experimental sites each containing a pair 10 x 40m rectangular plots. These sites include north and south facing aspects, subalpine and alpine tundra meadows in a range of hydrological conditions (e.g. dry meadows, moist meadows, wet meadows). We accelerated snowmelt in one plot of each block by adding chemically inert black sand, while keeping the second plot as an unmanipulated control; black sand was added to these plots after snow had naturally melted. This dataset includes measurements of plant species composition.

受气候变化影响，落基山脉前缘（Rocky Mountain Front Range）正经历夏季气温升高与融雪期提前的变化。积雪对高山生态系统的土壤温度调控、生长季时长及有效水分供给至关重要，因此无雪时段哪怕出现微小偏移，也可能产生显著影响。本研究依托黑沙延长生长季实验（Black Sand Extended Growing Season Length Experiment），旨在探究地形相关的气候暴露差异，如何通过融雪期提前的途径影响高山生境对气候变化的响应模式。为模拟气候暴露对植物群落的影响，NWT LTER研究人员设立了5个实验站点，每个站点包含一对10×40米的矩形样地。这些站点涵盖不同坡向（北坡、南坡）、不同水文条件下的亚高山与高山苔原草甸（例如干旱草甸、湿润草甸与湿生草甸）。研究团队通过在每个样地组的一块样地中施加化学惰性黑沙以加速融雪，另一块样地则作为未受人为干预的对照；所有样地均在积雪自然消融后施加黑沙。本数据集包含植物物种组成的测定数据。