The eastern Canadian Subarctic and Arctic are experiencing significant environmental change with widespread implications for the people, plants, and animals living there. In this study, we integrate 10 years of research at the Nakvak Brook watershed in Torngat Mountains National Park of Canada, northern Labrador, to assess the sensitivity of ecological and geomorphological systems to regional climate warming. A time series of the Normalized Difference Vegetation Index indicates that the area has undergone a significant greening trend over the past four decades. Analyses of shrub cross sections suggest that greening has been caused by a combination of rapid establishment and growth that began in the late 1990’s and coincided with warmer growing season temperatures. Recent (2010–2015) vegetation change has been subtle and heavily moderated by soil moisture status. Plant canopy height is greater in wet areas and has an insulating effect on ground surface temperatures during the winter, a consequence of snow trapping by shrub canopies. Observations of subsurface conditions indicate that the study site is best characterized as having discontinuous near-surface permafrost. The importance of subsurface conditions for above-ground vegetation depends on the geomorphological context, with plants in wet areas underlain by fine materials being the most likely to be growth-limited by permafrost, thus being potential hot-spots for future change. With the expectation of sustained climate change, loss of adjacent sea ice, and proximity to the forest-tundra ecotone, it is likely that the Torngat Mountains will continue to be an area of rapid environmental change in the coming decades.

加拿大东部的亚北极和北极地区正经历着重大的环境变化，对居住在那里的人，植物和动物具有广泛的影响。在这项研究中，我们整合了拉布拉多北部加拿大Torngat山国家公园内Nakvak Brook流域的10年研究，以评估生态和地貌系统对区域气候变暖的敏感性。归一化植被指数的时间序列表明，该地区在过去四十年中经历了明显的绿化趋势。灌木横断面的分析表明，绿化是由1990年代后期开始的快速建​​立和生长相结合引起的，并且与生长季节温度升高相吻合。最近（2010-2015年）的植被变化因土壤水分状况而变得微妙而严重。在潮湿地区，植物冠层的高度更高，并且在冬季对地面温度具有绝缘作用，这是灌木冠层积雪的结果。对地下条件的观察表明，研究地点的最佳特征是具有不连续的近地表多年冻土层。地下条件对于地上植被的重要性取决于地貌学背景，在湿润地区的植物中，精细材料最有可能受到多年冻土的限制，因此成为未来变化的潜在热点。期望持续的气候变化，邻近海冰的流失以及邻近森林冻原的过渡带，