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Recent literature has demonstrated the importance of fieldwork in geology. However, as resources become scarce, field experiences are often targeted for cuts. This was the case at the University of Calgary when massive enrollments placed a tremendous burden on resources. In courses throughout, field trips and other excursions were eliminated, making it so students do not have any field experiences until their third year. In response, we have developed three virtual field experiences (VFEs) of geologically relevant locations near Calgary. A burgeoning technology, VFEs offer advantages of convenience and versatility when compared to actual field trips. Our VFEs comprise drone-captured images used to form high-resolution 2-D photomosaics and 3-D computer models. We piloted one VFE in an introductory geology course. We wanted to understand how students engaged with the models so that we could make the VFE as effective as possible. Observing student engagement over two iterations allowed us to make changes to the activity. We found that students had difficulties with the VFE's open endedness. They also demonstrated difficulty with the relationship between observations and inferences. This is indicative of a broader issue with how geology (or science in general) is taught. Traditional instruction in geology places great emphasis on the \"what\" of geology as opposed to the \"how.\" We contend that teaching geology with more emphasis on how geology works will help students develop a better understanding of the relationship between inference and observation, enhancing their fieldwork and their understanding of science.

Alpine Treeline Ecotone (ATE), the typically gradual transition zone between closed canopy forest and alpine tundra vegetation in mountain regions, displays an elevational range that is generally constrained by thermal deficits. At landscape scales, precipitation and moisture regimes can suppress ATE elevation below thermal limits, causing variability in ATE position. Recent studies have investigated the relative effects of hydroclimatic variables on ATE position at multiple scales, but less attention has been given to interactions between hydroclimatic variables and disturbance agents, such as fire. Advances in monoplotting have enabled the extraction of canopy cover information from oblique photography. Using airborne lidar, and repeat photography from the Mountain Legacy Project, we observed canopy cover change in West Castle Watershed (Alberta, Canada; ~103 km2; 49.3° N, 114.4° W) over a 92-year period (1914–2006). Two wildfires, occurring 1934 and 1936, provided an opportunity to compare topographic patterns of mortality and succession in the ATE, while factoring by exposure to fire. Aspect was a strong predictor of mortality and succession. Fire-exposed areas accounted for 83.6% of all mortality, with 72.1% of mortality occurring on south- and east-facing slope aspects. Succession was balanced between fire-exposed and unburned areas, with 62.0% of all succession occurring on north- and east-facing slope aspects. The mean elevation increase in closed canopy forest (i.e., the lower boundary of ATE) on north- and east-facing undisturbed slopes was estimated to be 0.44 m per year, or ~44 m per century. The observed retardation of treeline advance on south-facing slopes is likely due to moisture limitation.

We used repeat oblique photography to quantify and determine the drivers of vegetation change, particularly forest closure and encroachment, in the Rocky Mountains of southern Alberta, Canada, from the beginning of the twentieth century to the present. We classified the landscape into seven distinct vegetation types (closed‐canopy conifer forest, broadleaf deciduous forest, mixedwood forest, open‐canopy woodlands, shrublands, grasslands and meadows, non‐vegetated) and assessed vegetation change between the two time periods. We found that closed‐canopy coniferous forest, broadleaf deciduous forest, and mixedwood forest increased on an area basis by 35%, 45%, and 80%, respectively, over this time period; concomitantly, grasslands and open‐canopy woodlands declined by 25% and 39%, respectively. Overall, 28% of the landscape was in a more advanced successional state in 2008 as compared to the early twentieth century. The Montane and Subalpine Natural Subregions (NSR) experienced the most change (42% and 26%, respectively, in a more advanced successional state). The loss of open‐canopy woodlands was observed across the entire landscape, while grassland and meadow losses were most acute in the Subalpine and Alpine NSRs. The probability of vegetation change to a more advanced successional condition was greater at higher elevations and in areas receiving lower amounts of solar insolation. The changes observed are consistent with what we would expect to see due to lengthening of fire return intervals. Understanding the magnitude of change in vegetation types and the drivers of this change is important for the development of effective contemporary ecosystem management and restoration practices.

Estimates of rates of wetland loss are important for understanding whether wetland policies meet their objectives. In Alberta, a no-net-area loss interim wetland policy was introduced in 1993. We tested the effectiveness of this interim wetland policy. A historical wetland inventory was established by generating a wetland inventory using digital topographic analysis and calculating a wetland-area vs. wetland-frequency power-law function from these data. Permanent wetland loss (topographic depression no longer exists) was calculated as the deviation from the historical wetland-inventory power-law function (representing the pre-settlement wetland inventory) and was estimated at 32.8% in number and 2.10% in area, with uncertainty estimates well below 1%. Temporary wetland loss (topographic depression remains on the landscape) was calculated as the difference between the historical wetland inventory and a time series of contemporary wetland inventories mapped from aerial photographs. Results indicate that as of 1993, 49.4% of the number of wetlands were temporarily lost (56.6% of wetland area), which increased in 2011 to 56.8% (68.0% of wetland area), with uncertainty estimates well below 1%. From 1993 to 2011, we estimated a rate of loss of 0.63% in wetland area/year. Wetland loss continued despite the introduction of the no-net-area-loss policy in 1993.

ContextHabitat loss and isolation are leading threats for biodiversity. Alpine habitat throughout the world is being lost and fragmented by forest encroachment. Previous analysis of forest encroachment from 1952 to 1993 in a population network along Jumpingpound Ridge, Alberta, Canada showed a 78% loss in meadow area, resulting in an estimated 41% reduction in dispersal of the alpine butterfly Parnassius smintheus.ObjectivesHere, we pursue three questions. First, has forest encroachment continued since 1993? Second, if so, has it affected butterfly dispersal? And third, have any changes altered estimates of metapopulation persistence of this species?MethodsThe area of each meadow and distance between each pair of meadows were determined in GIS using aerial photographs taken in 1952, 1993, 1999, 2008, and 2012. Mark-recapture (1995–2015) and landscape data were used to estimate annual butterfly dispersal and network persistence.ResultsAlpine meadows along Jumpingpound Ridge continued to be fragmented by encroaching forest showing a decrease in area and increase in the amount of forest between them. Annual dispersal parameters varied over the study, but the only consistent response to forest encroachment was an increase in male dispersal distance within meadow habitat. Estimates of metapopulation capacity also varied greatly among years due to variability in dispersal. The network was predicted to persist based on nearly all estimates.ConclusionsMetapopulation capacity is a potentially powerful tool for conservation, but interannual variability in dispersal hampers its utility under realistic conditions and could result in erroneous conclusions regarding metapopulation persistence. The 7 km long network of 18 subpopulations of Parnassius smintheus along the Jumpingpound Ridge and Cox Hill is currently at little risk of extinction due to forest encroachment.

Montane regions throughout western North America have experienced increases in forest canopy closure and forest encroachment into grasslands over the past century; this has been attributed to climate change and fire suppression/exclusion. These changes threaten ecological values and potentially increase probabilities of intense wildfire. Restoration of landscapes to historical conditions has been proposed as a potential solution. We used historical oblique photographs of an area in the Rocky Mountains of Alberta, Canada, to determine the vegetation composition in 1909 and then asked whether restoration to a historical vegetation condition would: (1) reduce the overall burn probability of fire; (2) reduce the probability of high‐intensity fires; and (3) change the spatial pattern of burn probabilities, as compared to current conditions. We used the Burn‐P3 model to calculate the overall and high‐intensity burn probabilities in two scenarios: (1) the baseline (current (2014) vegetation composition) and (2) historical restoration (vegetation in the study area as of 1909 with the surrounding landscape in its current condition). In the baseline, the landscape had 50% less grassland and more coniferous forest than 100 yr ago. Except for the fuel grids, we ensured all input parameters (number and locations of ignitions, weather conditions, etc.) were identical between the two scenarios; therefore, any differences in outputs are solely attributable to the changed fuels. The historical restoration scenario reduced the overall burn probability by only 1.3%, but the probability of high‐intensity wildfires was reduced by nearly half (44.2%), as compared to the baseline scenario. There were also differences in the spatial pattern of overall burn probabilities between the two scenarios. While 6.7% of the landscape burned with half (or less) the probability in the restoration scenario (compared to the baseline), other areas (3.2%) had burn probabilities two to five times higher. More than 21.5% had high‐intensity burn probabilities that were 20% or less of those in the baseline scenario. Differences in burn probabilities between the two scenarios were largely attributable to the effects of the vegetation difference on rate of fire spread. Restoration to historical vegetation structure significantly lowered wildfire risk to the landscape.

Surface mine operators in the Athabasca Oil Sands Region (AOSR) of northeastern Alberta are required by regulation to mitigate habitat impacts resulting from their operations, including impacts to wetlands. To date, most land reclamation efforts have focused on recreating upland forestlands that resemble the surrounding natural (dry) boreal forest. However, the surficial conditions on these reclaimed upland sites can also promote spontaneous wetland development. At Suncor’s Base Plant mine, opportunistic wetlands occurring on reclamation sites have not been formally included in the current inventory of reclaimed wetland areas and remain largely unquantified. We characterized and delineated an estimated 210 ha of opportunistic wetlands (consisting of shallow open water, marshes, and swamps) using aerial photo interpretation and remote sensing analysis in combination with follow-up field verifications. The remote-based (desktop) delineations consistently underestimated actual wetland extents, due mainly to underestimations in the extent of non-inundated vegetation zones (e.g., wet meadow) as well as shrubby swamp. After field corrections, opportunistic wetland habitat was estimated to constitute ~ 17% of the total study area (1209 ha), representing more than a fourfold increase in aerial wetland extent associated with reclaimed landforms over that delineated prior to this study. The interspersion of opportunistic wetlands with upland reclaimed landforms, although unintended, more closely reflects the pre-disturbance landscape, which was characterized by a matrix of forestlands, peatlands, and mineral wetlands (in contrast to the more peatland-dominated lowlands). At Suncor, wetland vegetation composition varied significantly across the study area and was influenced by topographic variation (e.g., in elevation and % slope) in combination with the reclamation substrates (soils) that were placed prior to seeding/planting. Thus, the inclusion of opportunistic wetland delineation in reclamation tracking and closure planning merits consideration as does the opportunity to manipulate current reclamation practices to promote the establishment and persistence of wetlands on reclaimed landforms.

The stability and deformation behavior of high rock slopes depends on many factors, including geological structures, lithology, geomorphic processes, stress distribution, and groundwater regime. A comprehensive mapping program is, therefore, required to investigate and assess the stability of high rock slopes. However, slope steepness, rockfalls and ongoing instability, difficult terrain, and other safety concerns may prevent the collection of data by means of traditional field techniques. Therefore, remote sensing methods are often critical to perform an effective investigation. In this paper, we describe the application of field and remote sensing approaches for the characterization of rock slopes at various scale and distances. Based on over 15 years of the experience gained by the Engineering Geology and Resource Geotechnics Research Group at Simon Fraser University (Vancouver, Canada), we provide a summary of the potential applications, advantages, and limitations of varied remote sensing techniques for comprehensive characterization of rock slopes. We illustrate how remote sensing methods have been critical in performing rock slope investigations. However, we observe that traditional field methods still remain indispensable to collect important intact rock and discontinuity condition data.

We used mark-recapture methods to estimate the number of Parnassius smintheus (Papilionidae) butterflies moving among 20 alpine meadows separated by varying amounts of forest along the east slope of the Rocky Mountains in Alberta, Canada. We combined generalized additive models and generalized linear models to estimate the effects of intervening habitat type and of population size on butterfly movement. By incorporating habitat-specific distances between patches, we were better able to estimate movement compared to a strictly isolation-by-distance model. Our analysis estimated that butterflies move readily through open meadow but that forests are twice as resistant to butterfly movement. Butterflies also tended to stay at sites with high numbers of butterflies, but readily emigrate from sites with small populations. We showed that P. smintheus are highly restricted in their movement at even a fine spatial scale, a pattern reflected in concurrent studies of population genetic structure. As an example of the utility of our approach, we used these statistical models, in combination with aerial photographs of the same area taken in 1952, to estimate the degree to which landscape change over a 43-year interval has reduced movement of butterflies among subpopulations. At these sites, alpine meadow habitat has declined in area by 78%, whereas the estimated effect of fragmentation has been to reduce butterfly movement by 41%.

Between 1857 and 1860 the British North American Expedition, led by Captain John Palliser, explored and surveyed the Canadian Prairies primarily to establish its suitability for agriculture and settlement. Historical and paleoclimate records indicate the Expedition coincided with below normal precipitation, leading to the perception of an arid or semi-arid region that would ‘forever be comparatively useless’ for agriculture. Today, this part of the Canadian Prairies is known as the Palliser Triangle, and is Canada’s productive dryland agricultural region. Here we present historic, geomorphologic, and chronometric evidence to reconstruct the landscape encountered by the Expedition. We contend that Palliser’s perception of the region was strongly influenced by his experience travelling through active sand dunes in the Middle Sand Hills of southeastern Alberta. At present, the dunes are entirely stabilized by vegetation, in contrast to Palliser’s report of ‘miles of burning sand’. Archival aerial photographs and optical ages of near-surface samples are used to reconstruct the landscape encountered by the Expedition in the Middle Sand Hills. Optical ages of presently stabilized sand dunes date primarily to between ad 1850 and 1934, peaking in c. ad 1925, and are indicative of a dune field undergoing reduction in activity, prior to the onset of 20th century droughts. Ages of interdune sand sheets further attest to regional dune activity occurring at least since ad 1750, concurrent with activity in other southern Canadian Prairie dune fields. Collectively, this evidence supports observations by Palliser of severe travelling due to bare sand conditions in 1857–1859. These conditions and Palliser’s inference of their extent influenced his perception of a ‘central desert’, thus delaying construction of the Canadian Pacific Railway along a southern route and postponing the westward colonization of Canada.