Biogeochemical geography of peatlands from in-situ measurements to satellite imagery

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Peatlands play a significant role in the global carbon cycle as well as in the maintenance of biodiversity and the protection of endangered species. Northern peatlands store one third of the terrestrial carbon derived from atmospheric carbon dioxide. Nevertheless, far less is known about their structure and function in comparison to other terrestrial ecosystems. Despite their resilience, peatlands are vulnerable to climate change, disturbance and land use change impacts. Precise information about their structure and functioning at landscape scales (and over time) is needed in order to inform policy regarding their management and conservation. Remote sensing and geospatial modelling offer the opportunity to better understand these ecosystems at large spatial scales through time. My research program aims to fill key knowledge gaps regarding the biogeochemical geography of peatlands from remotely sensed data. My long-term objectives are: 1) To determine the effect of scaling remotely sensed vegetation characteristics of peatlands from in-situ measurements to satellite imagery; and 2) To improve models of peatland carbon balance from imaging spectroscopy in light of projected climate change. Four scientific questions guide my proposed research program: 1) How is the anisotropic reflectance of peatlands affected by the illumination conditions (i.e. solar azimuth and zenith angle) during acquisition of airborne hyperspectral imagery? 2) Considering phenology, what is the spectral variability of peatland vegetation physiognomic classes? 3) With what precision can we determine the water table position (or a proxy) from optical imagery for peatlands as a means to model net ecosystem exchange at large spatial scales? and 4) Based on projected climate change, how will the extent of the different vegetation physiognomic classes change across the peatland? With 12% of its surface area estimated to be peatland, Canada has a clear stewardship obligation. The results from this research program would increase the understanding of the importance of this ecosystem as a climate change mediator and provider of fundamental ecosystem services.