Remote Sensing of Vegetation Types, Productivity and Change in the Canadian High Arctic

北极生态系统是在全球气候和环境变化背景下研究的至关重要的系统。然而，由于地处偏远和后勤方面的挑战，对北极植被状况的研究在很大程度上仍然不足。北极生态系统覆盖全球约500万平方公里，其中近一半的空间范围属于加拿大的主权范围（即，2.4百万平方公里）。科学家们已经确定，在北极地区观察到的气候变化信号最强（即，在高纬度）。这种变暖将对北极植被产生广泛而多样的影响;即，植物生长将增加物种丰富度、生物多样性和繁殖成功率，并对其产生不同影响，从而改变群落边界、组成和整个生态系统进程。卫星遥感数据为估计和监测植被提供了机会。然而，在加拿大北极地区利用高空间分辨率遥感数据（<10米）对植被类型特征和生物物理变量建模进行的研究有限，也没有研究这些变量如何与生态系统过程联系在一起（例如，碳通量/净生态系统交换）。这项研究需要详细的实地研究，以校准和验证适当的遥感模型，以高空间分辨率估计这些变量。我的研究将开发遥感方法来分类生态意义的植被类型，量化植被生物物理特性（即，覆盖率、碳交换），并将这些措施跨尺度联系起来，以研究植被/景观在空间和时间上的反应。 2017年，北极监测和评估计划报告说：“北极的气候正在向一个新的状态转变。北极地区的气候变化一直在快速发展。“2018年，政府间气候变化专门委员会报告说，北极的变暖正在并将继续比全球平均水平高出两到三倍。由于北极变暖的明确证据，加拿大有可能成为评估变暖对北极各种生态系统影响的领导者。我的研究结果将使我们能够评估整个北极陆地生态系统的环境变化，并估计未来的反馈情景。这项研究将帮助我们为在加拿大北部生活和经营的社区和资源行业的发展决策和适应战略提供信息。在五年的资助期内，我将培训3名博士生，4名硕士生和3名学士（荣誉）学生，他们将在加拿大北极地区进行研究，从而为下一代北极科学家和从业者做出贡献，他们专门接受北极实地方法，遥感图像处理和空间数据分析的培训。我的研究将为监测北极陆地生态系统和地形对气候变化的反应提供方法。

Arctic ecosystems are critically important systems to study within the context of global climate and environmental change. However, due to its remoteness and logistical challenges, research on Arctic vegetation condition remains largely understudied. Arctic ecosystems cover approximately 5 million km2 globally, with almost half of this spatial extent falling within Canada's sovereignty (i.e., 2.4 million km2). Scientists have determined that the strongest signals of climate change are being observed in the Arctic (i.e., at high latitudes). This warming will have widespread and diverse impacts on Arctic vegetation; i.e., plant growth will increase and differentially affect species abundance, biodiversity and reproductive success, thereby changing community boundaries, composition and overall ecosystem processes. Satellite remote sensing data provides an opportunity to estimate and monitor vegetation. However, there has been limited research conducted in the Canadian Arctic on characterizing vegetation types and modelling biophysical variables using high spatial resolution remote sensing data (<10 m); nor how these are linked to ecosystem processes (e.g., carbon flux/net ecosystem exchange). This research requires detailed in situ studies to calibrate and validate appropriate remote sensing models to estimate these variables at high spatial resolutions. My research will develop remote sensing methods to classify vegetation types of ecological significance, quantify vegetation biophysical properties (i.e., percent cover, carbon exchange) and link these measures across scales to examine vegetation/landscape response spatially and temporally. In 2017, the Arctic Monitoring and Assessment Program reported that "The Arctic's climate is shifting to a new state." and that "Climate change in the Arctic has continued at a rapid pace." In 2018, the Intergovernmental Panel on Climate Change reported that warming in the Arctic is, and will continue to be, two to three times higher than the global average. With clear evidence of warming in the Arctic, Canada has the potential to be a leader in evaluating the impacts of warming on diverse Arctic ecosystems. The results of my research will enable our ability to assess environmental change across Arctic terrestrial ecosystems and estimate future feedback scenarios. This research will help us inform development decisions and adaptation strategies for communities and resource industries living and operating in Canada's North. Over the five year granting period, I will train 3 PhD candidates, 4 MSc candidates and 3 BSc (Hons) students who will conduct research in the Canadian High Arctic, thereby contributing to the next generation of Arctic scientists and practitioners specifically trained in Arctic field methods, remote sensing image processing and spatial data analysis. My research will provide methods for monitoring the response of Arctic terrestrial ecosystems and terrain to a shifting climate condition.