Carbon and hydrology in the subarctic – measuring and modelling
Northern peatlands contain 25 % of the world’s terrestrial carbon and act as both a sink and source for CO2 and CH4, respectively. Between 30-50 % of northern peatlands occur in permafrost areas and global warming can radically alter their hydrology. Since water storage is a principal control on the rate and pathways of organic matter decomposition this will likely lead to dramatic changes in the greenhouse gas function of peatlands.
However, this feedback is not yet fully incorporated into models because the links between permafrost change, hydrology, and ecosystem biogeochemistry are crudely parameterized. We address this issue by applying spatially distributed hydrological modelling to high resolution LIDAR derived digital elevation models (DEM) in order to estimate the variance hydrology. Further, associated variations in the vegetation derived by remotely sensed data such as satellite and aerial imagery is evaluated against the measured and modelled hydrological data. The study site is the Stordalen peatland complex in Abisko, Sweden, which is currently experiencing permafrost loss. The results will be of value for global estimations of the northern peatland’s role in climate change.
The lateral (land-to-river) export of Dissolved Organic Carbon (DOC) from terrestrial to inland waters, specifically rivers, is poorly quantified in carbon biogeochemical cycle studies. In order to solve parts of this problem a PhD project with a multidisciplinary approach has been initiated.
The main parts of this is to use hydrological modelling and remote sensing together with measured data to investigate the spatial relationships of vegetation, landscape morphometry, peatland content hydrology and their impact on DOC.