The changing water cycle: the Boreal Plains ecozone of Western Canada

Abstract

The Boreal Plains Ecozone (BPE) in Western Canada is expected to be an area of maximum ecological sensitivity in the 21st century. Successful climate adaptation and sustainable forest management require a better understanding of the interactions between hydrology, climate, and vegetation. This paper provides a perspective on the changing water cycle in the BPE from an interdisciplinary team of researchers, seeking to identify the critical knowledge gaps. Our review suggests the BPE will likely become drier and undergo more frequent disturbance and shifts in vegetation. The forest will contract to the north, though the southern boundary of the ecotone will remain in place. We expect detrimental impacts on carbon sequestration, water quality, wildlife, and water supplies. Ecosystem interactions are complex, and many processes are affected differently by warming and drying, thus the degree and direction of change is often uncertain. However, in the short term at least, human activities are the dominant source of change and are unpredictable but likely decisive. Current climate, hydrological, and ecological monitoring in the BPE are limited and inadequate to understand and predict the complex responses of the BPE to human activities and climate change. This paper provides a case study of how hydrological processes critically determine ecosystem functioning, and how our ability to predict system response is limited by our ability to predict changing hydrology.

Seasonal ground ice impacts on spring ecohydrological conditions in a western boreal plains peatland

“…SGI melt did not begin until after the snow that fell on April 16 had melted, which resulted in low infiltrability for the peatland, and subsequently less snowmelt water likely remained within the peatland (Ireson et al, 2015;Watanabe et al, 2013). SGI melt did not begin until after the snow that fell on April 16 had melted, which resulted in low infiltrability for the peatland, and subsequently less snowmelt water likely remained within the peatland (Ireson et al, 2015;Watanabe et al, 2013).…”

“…WBP peatlands are under pressure from resource extraction in the Athabasaca Oil Sands Region, where they are removed during surface mining processes or impacted during other development activities (Rooney, Bayley, & Schindler, 2012), and from climate change (Ireson et al, 2015;Waddington et al, 2015), both of which can alter or remove peatlands, removing a water source from the landscape.…”

The changing water cycle: Burabay National Nature Park, Northern Kazakhstan

“…Climate change impacts on forest productivity and tree growth are already being documented across the boreal forests of North America, and are interpreted as signals of increasing drought stress. 49 Overall, each disturbance influences the forest communities differently. However, they all impact the way forests accumulate moisture and store carbon.…”

Landscape controls on long‐term runoff in subhumid heterogeneous Boreal Plains catchments

“…The result is a large and continually increasing demand for water resources with potentially significant impacts to water quantity and quality (Schneider, Devito, Kettridge, & Baynes, ). Concerns over long‐term water security are heightened by the close balance between potential ET (PET) and P in the region and low but highly variable long‐term runoff (Ireson et al, ; Mwale et al, ). Development of adaptive best management or reclamation practices to protect and address future water availability and cumulative impacts from a range of disturbances requires characterization of the dominant sinks and sources of water that control the magnitude and spatiotemporal variability of catchment runoff (Buttle, ; Winter, ).…”

“…Conceptual syntheses of research from across the BP (Devito, Mendoza, & Qualizza, ; Ireson et al, ; Johnson & Miyanishi, ), and similar ecohydrological regions (Schoeneberger & Wysocki, ; van der Kamp & Hayashi, ; Winter, ), predict large spatial variability in catchment hydrological function due to complex interactions of a dynamic climate with subtle variations in topographic relief, moderate to poor regional drainage, and spatially variable glacial deposits and soil‐vegetation land cover. Major differences in hydrologic function attributable to the surficial geology across the BP have been broadly categorized into three general glacial deposit textures: (a) coarse‐textured glacio‐fluvial and glacio‐lacustrine deposits, (b) fine‐textured clay‐rich hummocky moraines, and (c) fine‐textured clay‐rich glacio‐lacustrine plain deposits (Bridge & Johnson, ; Devito, Creed, Gan, et al, ; Ireson et al, ). These three glacial landforms encompass the spatial variations in recharge, water table configurations, scale and magnitude of surface‐groundwater interactions, and degree of surface and subsurface connectivity (Devito et al, ; Winter, ).…”