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Seventeen glacially sheared stumps in growth position and abundant detrital wood fragments were exposed by stream avulsion at the terminus of the Saskatchewan Glacier in 1999. The stumps lay buried beneath the glacier and over 5 m of glacial sediment until historical recession and stream incision exposed the 225- to 262-year-old stand of subalpine fir, Englemann spruce and whitebark pine trees. Crossdating and construction of two radiocarbon-controlled floating tree-ring chronologies showed that all the subfossil stumps and boles exposed at this location were killed during a Neoglacial advance of the Saskatchewan Glacier 2,910 ± 60 to 2,730 ± 60 ¹⁴C years B.P. These findings support the Peyto Advance as a regional glaciological response to changing mass balance conditions.

In the summer of 2010, fieldwork was conducted in the Robertson Valley, Canadian Rocky Mountains, Alberta to assess the magnitude and controls of microbial nitrification in proglacial till and in supraglacial, subglacial, and proglacial streams. Seasonal precipitation and glacial and proglacial runoff was sampled for hydrochemical and stable isotope analyses (δ18O and δ15N of nitrate [NO3-]). Lower Ca:Mg ratios, higher mean Σmajor ions, and an increased importance of reactions with slower dissolution kinetics in subglacial streams and proglacial seeps indicated waters here experienced longer rock-water contact time than in dilute supraglacial streams. Additionally, waters emanating from longer residence time flowpaths acquired substantial NO3- from nitrification reactions. Using δ18O-NO3- in a simple end-member mixing model, the fraction of NO3- derived from microbial nitrification was estimated to be 44 to 56% in the two subglacial streams, and greater than 80% in proglacial seeps. These results show that atmospherically-derived nitrogen (N) in this glacial valley undergoes substantial biological cycling prior to export in surface runoff. Water flowing from the east subglacial stream (RE) received a larger portion of its melt from a sediment-rich, slow drainage system and had a higher proportion of nitrified NO3- compared to the west subglacial stream (RW), where runoff was similar in composition to supraglacial runoff, indicating that the nature of subglacial flowpaths is an important factor in determining the amount of microbially-cycled nutrients that are exported from a glacier. Sixteen 34-day in situ soil incubations revealed that net mineralization and net nitrification occurred at all four sampling sites in the glacier forefield along a 1.6 km chronosequence; however, there was no significant difference among these rates with time since deglaciation or temperature. Instead, net mineralization and net nitrification rates were significantly correlated (p < 0.05, n = 16) with measured physical and chemical soil variables, including total organic carbon, total N, bulk density, pH, and clay content, suggesting that substrate availability is a larger control on N-cycling processes than time since deglaciation. High variability in inorganic soil N pools and N-cycling rates indicates that there are likely hot spots of biogeochemical activity within glacial till. / Thesis (Master, Geography) -- Queen's University, 2012-04-26 14:47:17.29

In the face of an expanding global human footprint, mammalian carnivores have become vulnerable to the effects of large-scale landscape change. Throughout North America, wide-ranging terrestrial carnivores have experienced significant species declines and range retractions. Understanding the complex and interacting effects of human-caused habitat disturbance on highly mobile species remains an ongoing challenge for ecologists. To address these challenges, studies commonly select a focal species to examine the adverse effects of human disturbance. Due to the paucity of multi-species study, little is yet known about the relative role interspecific interactions play within communities of carnivores in human-altered systems. In an effort to address this knowledge gap, I examined occurrence patterns of one species known to be sensitive to human disturbance – the wolverine – and compared occurrence patterns among multiple carnivores across a gradient of increasing human land use within a rugged and heterogeneous landscape in the Canadian Rocky Mountains of Alberta. I surveyed carnivore occurrence by combining remote camera trapping and non-invasive genetic tagging. Using a systematic grid based design, medium to large sized carnivores were detected over an area approximately 15,000km2. Consistent with the literature, I found wolverines to be less likely to occur outside of protected areas boundaries and with increasing human-caused landscape disturbance. Contrary to recent climate-focused hypotheses, the spatial pattern of wolverine occurrence was best explained by cumulative effects. When modeling multiple carnivore occurrence across this spatial gradient of human land use, no generality in response was observed. However, a consistent and distinct dissimilarity in response to natural and anthropogenic landscape features was found between wolverine and coyote. The patterns of occurrence led me to infer that habitat condition in the more human-altered systems found along eastern slopes of the Canadian Rocky Mountains is less suitable for some more sensitive species and benefits more human-adapted species. I further hypothesized that an indirect and additive effect of human disturbance is increased interspecific competition between co-occurring carnivores that differentially respond to changes in habitat condition. My results emphasize that by broadening our scope to investigate both single and multiple species, ecologists and managers may better understand the full suite of factors influencing current and future distribution patterns. / Graduate / heimnikki@gmail.com

Remote ecosystems in Canadian Rocky Mountain parks and protected areas are being pressured by indirect impacts of human activities across the landscape. Ecological impacts can result from a variety of stressors such as climate change, fire suppression and prescription, visitor use, invasive species, and surrounding land-uses. With intensified challenges relating to logistics and moral issues inherent in remote ecosystem management (Higgs and Hobbs, 2010; Higgs and Roush, 2011), managers of these landscapes continue to struggle with questions of "what do we do here?" For ecological restoration and conservation management, historical landscape changes (predominantly following years of fire suppression and rapid climate change) are complicating decisions and our understanding of ecological processes. While intervention may become increasingly necessary for maintaining biodiversity and ecosystem services under conditions of rapid change (Hobbs et al., 2011), direct action may not be the most appropriate tactic, especially when lacking adequate information and foresight (Harris et al., 2006; Higgs and Roush, 2011). This study investigates observable historical remote landscape change in two protected areas in the Canadian Rockies, and examines the resulting implications for management and restoration. Present conditions in Willmore Wilderness Park and Mount Robson Provincial Park were evaluated in a comparative case-study approach. The influence of factors such as jurisdiction, climate, socioeconomics and settlement history were seen to strongly shape how environmental changes impacted management efforts and decisions. Long-term landscape changes were observed through repeat photography with the Mountain Legacy Project. Through focus groups using photo-elicitation with park managers, repeat photo pairs guided discussion. I pursued this research question: "how do long-term landscape changes influence conservation and restoration objectives in remote mountain ecosystems?" This also incorporated subsidiary questions: "what are the inherent challenges in managing (and restoring) remote ecosystems?” and “how could managers of remote ecosystems best approach these issues in the face of rapid ecological change?” Significant landscape changes are observed in both parks and include glacier retreat, forest stand aging, valley infill (encroachment) and upward movement of the treeline ecotone. While ecological changes are seen as significant and as threatening to various park values and public safety, efforts to better understand these changes or address them are limited. The majority of remote ecosystem management efforts in both parks are indirect (passive), with the exception of fire management. This is largely due to capacity and resource constraints, and agency recreation mandates and visitor needs monopolizing manager focus. Suggested restoration efforts would assist climate adaptation and reduce indirect impacts without placing notable pressure on remote ecosystems. The use of repeat photography for monitoring of ecological change is a strong possibility for parks management, particularly if public engagement through citizen science was implemented to minimize dependence on management resources. / Graduate / 0368 / 0768 / jlfalk@uvic.ca

Remote ecosystems in Canadian Rocky Mountain parks and protected areas are being pressured by indirect impacts of human activities across the landscape. Ecological impacts can result from a variety of stressors such as climate change, fire suppression and prescription, visitor use, invasive species, and surrounding land-uses. With intensified challenges relating to logistics and moral issues inherent in remote ecosystem management (Higgs and Hobbs, 2010; Higgs and Roush, 2011), managers of these landscapes continue to struggle with questions of "what do we do here?" For ecological restoration and conservation management, historical landscape changes (predominantly following years of fire suppression and rapid climate change) are complicating decisions and our understanding of ecological processes. While intervention may become increasingly necessary for maintaining biodiversity and ecosystem services under conditions of rapid change (Hobbs et al., 2011), direct action may not be the most appropriate tactic, especially when lacking adequate information and foresight (Harris et al., 2006; Higgs and Roush, 2011). This study investigates observable historical remote landscape change in two protected areas in the Canadian Rockies, and examines the resulting implications for management and restoration. Present conditions in Willmore Wilderness Park and Mount Robson Provincial Park were evaluated in a comparative case-study approach. The influence of factors such as jurisdiction, climate, socioeconomics and settlement history were seen to strongly shape how environmental changes impacted management efforts and decisions. Long-term landscape changes were observed through repeat photography with the Mountain Legacy Project. Through focus groups using photo-elicitation with park managers, repeat photo pairs guided discussion. I pursued this research question: "how do long-term landscape changes influence conservation and restoration objectives in remote mountain ecosystems?" This also incorporated subsidiary questions: "what are the inherent challenges in managing (and restoring) remote ecosystems?” and “how could managers of remote ecosystems best approach these issues in the face of rapid ecological change?” Significant landscape changes are observed in both parks and include glacier retreat, forest stand aging, valley infill (encroachment) and upward movement of the treeline ecotone. While ecological changes are seen as significant and as threatening to various park values and public safety, efforts to better understand these changes or address them are limited. The majority of remote ecosystem management efforts in both parks are indirect (passive), with the exception of fire management. This is largely due to capacity and resource constraints, and agency recreation mandates and visitor needs monopolizing manager focus. Suggested restoration efforts would assist climate adaptation and reduce indirect impacts without placing notable pressure on remote ecosystems. The use of repeat photography for monitoring of ecological change is a strong possibility for parks management, particularly if public engagement through citizen science was implemented to minimize dependence on management resources. / Graduate / 0368 / 0768 / jlfalk@uvic.ca