Western Boreal Forest Ecohydrology – Natural and Impacted Systems

Continued integrated research aimed at improving the understanding of ecohydrological processes in peatlands and forests in the Western Boreal Forest (WBF), and the cumulative effects of land-use change and climate variability on their water and carbon cycling. This research is significant as it provides a quantitative understanding of the integrated responses of peatland and forest systems to larger scale climatic and regional scale anthropogenic stresses, which will provide new knowledge, data and improved conceptual frameworks for ecosystem and hydrological modelling and ecosystem reclamation.The current research program is being conducted at research sites near Utikuma Lake, Lac La Biche and Fort McMurray in the boreal forest of Alberta. Research areas include hydrology, hydrogeology, hydrometeorology, water resources engineering, forest hydrology, ecology, and biogeochemistry. Basic research into the hydrologic function of boreal forests and their surrounding wetlands will provide natural resource companies with improved tools to limit ecohydrologic impacts of their activities, and will guide oil sands companies in their efforts to reclaim mining sites to functional ecosystems. Financial support from foil and gas companies, Alberta Environment and Parks, and NSERC are in place. Related projects are addressing the hydrology and hydrogeology of reclaimed oil sands sites.

The research program is actively soliciting graduate students at both the master’s (Masters of Science (MSc)) and doctoral levels to undertake a variety of field research and computer modelling projects starting over the next 4 years. General descriptions of proposed projects are below.

GRADUATE STUDENT POSITIONS

MSc

Positions will begin in 2018 to examine internal (within) peatland ecohydrological interactions, to quantify the feedbacks among surface energy and mass fluxes and canopy cover (tree type and density), and the feedbacks between radiation exchange at the peatland surface and shifts in surface vegetation communities, and resulting effects on water use efficiency and boundary layer conditions. This research will be done using an established network of 8 sites (existing and new data) that I have been conducting research at for ~15 years in the Boreal Plains (BP) region of North-Central Alberta comparing peatland ecohydrological function among peatlands of differing degrees of canopy cover density, and dominant species.

Another MSc student is being sought to examine the feedbacks between tree growth and aerodynamic properties of peatlands by modelling the turbulent interactions of within peatlands of differing canopy structures. This project will improve knowledge of the role of within-peatland tree canopies in controlling turbulent conditions and ET losses, which will strongly inform how resilient systems may be to climate change where changes in peatland tree cover accompanying hydrological changes are expected to be one of the main responses.

Results from these projects will provide insight on small-scale, within peatland hydrological feedbacks with overstory vegetation and the net effects on ET and WUE. This will provide information on process interactions and thresholds that may exist in canopy development, necessary to quantify peatland response to disturbance and resilience to climate change. 

PhD

This position will begin in 2018 and study the influence of aspen stand age on carbon function recovery. This research will compare aspen stands of similar ages of above ground biomass but of different stand/root maturities by examining recently planted stands and recently harvested mature stands. The student will address changes in hydrological, nutrient and carbon cycling, as well as upland and peatland connectivities, and be involved in the development of lump modelling and determining functional responses to land use changes. Certain aspects of this research direction could be partitioned into MSc projects as well.

MSc

This position will begin in 2018 and build on
ongoing research on natural variability in CO2 exchange within natural  peatlands along a gradient in ground ice conditions (seasonal ice to discontinuous permafrost) by examining and modelling changes in peatland water and nutrient cycling as a function of ground thermal processes.The objectives of this project are to examine/model the influence of ground ice conditions on the microclimate and hydrologic pathways, and therefore plant and microbial activity in peatlands. This will provide a more useful tool to landuse managers in this region of the Boreal Forest, where hydrologic connections between peatlands and forests are of the utmost importance.



MSc
This position will begin in 2016 and will monitor biogeochemical cycling in aspen forests of various ages. Microclimatic effects, soil/root hydraulic processes and canopy throughfall and stemflow are all expected to interact and influence biogeochemical cycling within the rooting zone of Western Boreal Plain forests. The degree of this interaction will largely be influenced by the age of the stand (clone) system – as with aspen the age/size of the above ground biomass is not necessarily indicative of the state of the clone root system. This research will integrate and use previous data from other undergraduate and graduate student work at sites in the Utikuma Lake and Fort McMurray regions of Northern Alberta.

MSc

DSC_0159Wildfire represents the largest natural disturbance in Canada’s WBF and is predicted to increase in both severity and area burned in the future. Assessing and mitigating the impact of wildfire in the WBF is challenging due to the combination of large spatial heterogeneity of deep glacial deposits with a sub-humid climate. This results in dynamic and complex surface and groundwater interactions and potentially a large range in sensitivity of aquatic systems to local and regional disturbance. This study takes advantage of the recent Fort McMurray wildfire, May 2016. Regional hydrogeological and local scale studies have been conducted in this area, beginning in 2012, on forest-wetland-aquatic hydro-chemical linkages located on a variety of landforms and in landscape positions representative of the WBF. Paired temporal (pre-, post-burned) and spatial (reference, burned) comparisons will be conducted to examine how short-term evapotranspiration and carbon exchange responds in the years immediately following the wildfire disturbance along interacting landscape gradients. The longer-term goal of the research will be to test and develop regional conceptual and numerical models predicting how heterogeneity in glacial surgical deposits and landscape position influencing the scale of groundwater – surface water interactions, and influence the resilience and resistance of forest-wetland-aquatic ecosystems to large scale wildfire disturbance.

This position will begin in 2018 and build on ongoing (pre-fire) research on natural variability in CO2 exchange within natural peatlands by examining, and modelling, changes in peatland water and carbon exchange as a result of fire. The objectives of this project are to model the response of atmospheric CO2 and evapotranspiration fluxes in four peatlands to fire in order to understand how the removal of canopy structure and ground cover alters the microclimate and hydrologic pathways, and therefore plant and microbial activity. This will provide a more useful tool to land use managers in this region of the Boreal Forest, where hydrologic connections between wetlands and forests are of the utmost importance.

PhD

Two fully funded PhD positions are required to examine the importance of forest–peatland interactions on peatland ET by examining the degree of upland sheltering on turbulent flows in fens of varying degrees of canopy cover using large eddy simulation modelling to compare how turbulent flows within the peatland respond to changes in the size, shape and orientation of the upland and peatland, and what the resulting effects are on the peatland mass and energy exchange; and, to scale this to the landscape to examine the the trade-off between water storage and sheltering between peatlands and forests (particularly small isolated and perched systems)  through ratios of wetland to forest area as a function of surficial geology, which can be further related to peatland size and orientation and the surrounding forest canopy characteristics. The latter project will utilize a variety of remote sensing products and approaches to relate the overall “health” or productivity of these areas to provide new knowledge of the internal (size, surface roughness and geometry) and external (surrounding vegetation height and large scale disturbances on the landscape (other peatlands)) controlling forces of a turbulent cavity and the impact it has on ET.

.