Black spruce (Picea mariana) peatlands play important ecologic and economic roles in the temperate-boreal region of North America, providing a valuable timber resource while also performing important ecosystem functions. Climate models project decreases in the amount of snowfall received throughout the temperate-boreal region by 2100, as average wintertime temperatures increase. We used a paired-plot experimental design to assess the effect of snow removal on soil temperature and frost development at six forested peatland sites in northern Minnesota, USA, during the three winters from 2017 to 2020. Treatments consisted of 1) removal of snow throughout the winter, or 2) ambient snow cover conditions. During the three years of the study, there was a significant effect of snow removal by mid-winter that continued into late winter and spring, where removal of snow increased soil frost depth compared to plots with ambient snow cover treatment. Soil temperatures in the removal plots were highly responsive to air temperature fluctuations to depths of 20 cm or more, whereas the ambient snow cover soils exhibited little fluctuation and maintained temperatures near or above 0° C for much of the winter season. We found that each cumulative freezing degree day resulted in an average of 0.36 cm of soil frost development in snow removal plots, as compared to 0.07 cm depth in the ambient treatment plots. Soils were significantly colder through much of the summer growing season in the removal treatment compared to the ambient treatment, with detectable soil frost in the soil profile as late as mid- to late-June. These results indicate that predicted changes in wintertime precipitation may result in increased development of soil frost in forested peatland systems, although some of this effect may be offset by predicted concurrent increases in air temperature. We did not measure indicators of biological activity, but the large and prolonged reduction in soil temperature with snow removal is likely to depress biological activity throughout the growing season and the many ecosystem functions it influences. Because of the role that soil temperature and frost play on the hydrologic and ecological processes of peatlands, as well as the crucial role of soil frost in peatland forest management, findings of this study provide important insight into the potential effects of altered winter conditions on these expansive and ecologically important ecosystems.

黑云杉（云杉云杉泥炭地在北美温带-北方地区发挥着重要的生态和经济作用，在提供宝贵的木材资源的同时，还履行着重要的生态系统功能。气候模型预测，随着冬季平均温度升高，到2100年，整个温带-北方地区的降雪量将减少。我们使用了成对实验设计，评估了2017年至2020年的三个冬季期间，除雪对美国明尼苏达州北部六个森林泥炭地站点土壤温度和霜冻发育的影响。处理包括1）在整个冬季除雪冬天，或2）周围的积雪状况。在这项研究的三年中，冬季持续到冬末和春季，除雪效果显着，与采用环境雪覆盖处理的地块相比，除雪增加了土壤霜冻深度。清除区的土壤温度对气温变化至20 cm或更大的深度有高度响应，而周围的积雪土壤几乎没有波动，并且在冬季的大部分时间内保持温度接近或高于0°C。我们发现，除雪区的每个累积冻结日平均导致0.36 cm的土壤霜冻发展，而环境处理区的深度为0.07 cm。与环境处理相比，在去除处理中，整个夏季生长期中的土壤明显较冷，直到6月中旬至后期，土壤剖面中都可检测到土壤霜。这些结果表明，预计的冬季降水变化可能导致森林泥炭地系统土壤霜的生长增加，尽管这种影响中的一部分可能被预计的同时气温升高所抵消。我们没有测量生物活性的指标，但是随着除雪的进行，土壤温度的长期大幅度下降很可能会抑制整个生长季节的生物活性，并影响许多生态系统功能。由于土壤温度和霜冻在泥炭地的水文和生态过程中所起的作用，以及土壤霜冻在泥炭地森林管理中的关键作用，因此本研究的发现提供了重要的见解，以了解冬季气候变化对这些因素的潜在影响。广阔且具有重要生态意义的生态系统。