Satellite-based assessment of coastal ocean productivity

沿海植被栖息地为人类提供了许多生态系统服务，是世界上最重要的碳汇之一，但它们的量化程度仍然很低。在全球范围内，生活在潮间带和潮下带的海洋大型植物对海洋净初级生产力(NPP)的贡献可能高达10%，但在沉积物中的碳埋藏量却占47%。潮间带和潮下带都有大型植物，包括生长在粉质和/或泥质沉积物上的海草，以及生长在岩石基质和巨石上的大型藻类。我们假设，作为对气候变暖的反应，植被繁茂的沿海生态系统将向北方扩张。北极和亚北极地区植被繁茂的沿海生态系统的扩张可能会在未来加拿大漫长海岸的碳封存中发挥重要作用，但缺乏量化工具。我的研究计划将利用卫星光学遥感技术的最新进展，评估近岸和浅水环境中海岸植被的动态。我提议的主要目的是了解北极和亚北极生态系统中海洋初级生产者的现状和演变。具体而言，我打算：1)使用从高到极高空间分辨率传感器的多光谱图像，评估亚北极和北极环境中植被覆盖的沿海生态系统的长期和短期变化；2)探索光学遥感在量化沿海生态系统中的净初级生产力和(或)有机碳埋藏等基于碳的过程方面的潜力；3)建立和验证光谱光和光合作用的预测模型。实地考察将沿着从南到北的坡度在沿海地区进行，从亚北极(圣劳伦斯河口和海湾、詹姆斯湾)到北极高地(南安普敦群岛、池塘海湾和比洛特群岛)。环境。14名HQP(6名B.SC、4名M.SC、3名Ph.D.和1名PDF)将在高度跨学科的环境中接受培训，学习卫星图像处理、地球测量学、就地水上光学、数值建模和计算机编程；随着监测沿海生态系统的需求增加以及地球观测技术的改进和产生越来越高质量的数据，所有这些领域的专门知识预计都将受到高度需求。由于对沿海生态系统的状况和演变有了新的认识，该项目将有事件决策者、北部沿海社区、原住民和非政府组织参与保护和恢复工作。该计划开发的量化工具将有助于评估沿海植被生态系统的社会经济重要性，在气候变化缓解战略的蓝碳战略背景下尤其如此。碳储量可以转化为货币价值，从而有助于决策过程。

Vegetated coastal habitats provide numerous ecosystem services to humans and are among the most important carbon sinks worldwide, yet they remain poorly quantified. At a global scale, marine macrophytes living in intertidal and subtidal zones may contribute as much as 10% of the marine net primary production (NPP) but 47% of the carbon burial in sediments. Macrophytes are found in both the intertidal and subtidal zones; they include seagrass, which grows on silty and/or muddy sediments, and macroalgae, which grows on rocky substrates and boulders. We hypothesize that vegetated coastal ecosystems will expand toward the north as a response to climate warming. Arctic and subarctic expansion of vegetated coastal ecosystems may play an important role in future carbon sequestration along the long Canadian coast, but quantitative tools are lacking. My research program will assess the dynamics of coastal vegetation in near-shore and shallow-water environments, capitalizing on recent advances in satellite optical remote sensing technologies. The main objective of my proposal is to understand the current state and evolution of marine primary producers in the arctic and subarctic ecosystems. Specifically, I intend to: 1) assess long- and short-term changes in vegetated coastal ecosystems in subarctic and arctic environments using multispectral imagery from high to very high spatial resolution sensors; 2) explore the potential of optical remote sensing to quantify carbon-based processes such as NPP and/or organic carbon burial in coastal ecosystems; and 3) develop and validate prognostic models of spectral light and photosynthesis in the optically complex and shallow waters encountered in subarctic coastal waters. Fieldwork will be performed in coastal zones along a south-to-north gradient, from subarctic (estuary and gulf of St. Lawrence, James Bay) to the High Arctic (Southampton Is., Pond Inlet, and Bylot Is.) environments. Fourteen HQP (6 B.Sc., 4 M.Sc., 3 Ph.D., and 1 PDF) will be trained in a highly interdisciplinary environment, learning satellite image processing, geomatics, in situ aquatic optics, numerical modelling, and computer programming; all these areas of expertise are expected to be in high demand as the needs in monitoring coastal ecosystems increase and Earth Observation technologies improve and produce increasingly high-quality data. This project will have incidence decision makers, coastal northern communities, First Nations, and NGOs in conservation for preservation and restoration efforts because of the new knowledge on the state and the evolution of the coastal ecosystems. Quantitative tools developed by this program will contribute to assessing the socio-economic importance of vegetated coastal ecosystems, which is particularly true in the context of the Blue Carbon strategy of the climate change mitigation strategy. Carbon stock may be converted into monetary values and therefore help in decision-making processes.