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The main objective of this paper is to describe the characteristics of brash ice in the St. Lawrence River downstream of Montréal over a period of three winters. We used two instruments deployed in the St. Lawrence River navigation channel through Lake St. Pierre to measure ice parameters: an acoustic Doppler current profiler (ADCP) and an ice-profiling sonar (IPS). This paper discusses the capacities of these instruments to quantify ice characteristics and to predict the risk of ice congestion. It was found that wind velocity and air temperature play major roles in the variation in ice parameters and, consequently, in the occurrence of ice congestion in the navigation channel through Lake St. Pierre. Comparison of the IPS and ADCP data showed good agreement and demonstrated that these two instruments can be very effective for certain ice applications. [ABSTRACT FROM AUTHOR]

All too often, engineering strategies aimed at improving road safety are reactions to existing problems that occur after a road has been designed and built. Targeting problem locations and developing plans to reduce collisions are vital and have proven to be very successful. Transportation professionals, however, should also take a proactive approach to address road safety before problems emerge. This paper describes an evolving need of how to deal with road safety in a proactive manner. Although a proactive approach should improve the overall safety performance, there is currently a poor understanding of how to proactively plan for road safety. Several logistical and technical obstacles hinder the effective planning for road safety. Each of these obstacles is presented in detail, followed by a description of the opportunity to overcome each obstacle. The paper also includes the results of a case study used to demonstrate the proposed process. A proactive approach to road safety complements traditional, reactive methods currently in use. Significant progress will be realized once safety professionals shift their focus from fixing existing problems to helping plan roads that attempt to be problem free. The net result should be a safer road system. [ABSTRACT FROM AUTHOR]

This paper presents a simplified approach to quantify the contribution of individual factors to the historical growth or decline in total travel between two points in time. The method employs person trip rates and distributions of the individual characteristics at the two time points to determine the portion of urban person travel increase or decrease associated with the change in each factor. The paper presents the application of the approach to investigate changes in person travel in the Greater Toronto Area between 1986 and 1996. Specifically, the study determined the change in person travel attributed to each of the following factors independently: change in population size, change in age distribution, change in residential location distribution, and change in employment status distribution (full time, part time, work at home). The data were obtained from the 1986 and 1996 Transportation Tomorrow Surveys (TTSs).Key words: transportation planning, travel demand.Cet article présente une approche simplifiée afin de quantifier la contribution des facteurs individuels à l'augmentation/diminution historique du nombre total de voyages entre deux points dans le temps. La méthode utilise les taux de déplacements des individus et les distributions des caractéristiques individuelles aux deux points dans le temps afin de déterminer l'augmentation/diminution de la portion des déplacements des individus en ville associée au changement de chaque facteur. Ensuite, l'article présente l'application de l'approche afin d'étudier les changements des déplacements des individus dans le Grand Toronto entre 1986 et 1996. Plus particulièrement, l'étude a déterminé que le changement dans les déplacements des individus est attribué à chacun de ces facteurs indépendants, soit le changement dans la taille de la population, le changement dans la distribution de l'âge, le changement dans la distribution des locations résidentielles et le changement dans la distribution du statut d'emploi (temps plein, temps partiel, travail à la maison). Les données ont été obtenues dans le Transportation Tomorrow Surveys (TTS) de 1986 et 1996.Mots clés : planification des transports, demande de déplacements.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

In Canada, over 300 heavy vehicles equipped with central tire inflation systems are being used in forestry, mining, and grain hauling. Since 1995, Saskatchewan Highways and Transportation has permitted truck fleets to operate with primary highway axle loads on secondary highways under a partnership program. This paper reports on the comparison of rutting progression on an accelerated field experiment utilizing standard and reduced tire pressures. The experiment was conducted by Saskatchewan Highways and Transportation in the Big Quill Lake area of southern Saskatchewan. The vehicles used in the experiment were nine-axle B trains, eight-axle B trains, and six-axle semi-trailers. The statistical analysis of rutting data presented in the paper shows that reduced tire pressures can effectively extend the pavement service life of gravel and thin membrane surfaced roads. On the thin membrane pavements, there was less rutting on the low-pressure lane until twice as many vehicles had trafficked the road, and rutting was no worse on the low-pressure lane even when 10 times as many vehicles had trafficked the road. On the gravel surface, rut depth was lower on the low-pressure lane until twice as many trucks had trafficked that lane.Key words: rutting, pavement, central tire inflation, tire pressure, low-volume roads, unsurfaced roads.Au Canada, plus de 300 véhicules lourds équipés de systèmes centraux de gonflement des pneus sont en usage dans les secteurs forestier et minier et pour le transport de grains. Depuis 1995, le département des autoroutes et des transports de la Saskatchewan (« Saskatchewan Highways and Transportation ») a permis aux flottes de camions d'opérer sur des autoroutes secondaires avec des charges aux essieux pour autoroutes primaires dans le cadre d'un programme de partenariat. Cet article se penche sur la comparaison de la progression de l'orniérage lors d'un essai accéléré sur le terrain en utilisant des pressions normales et réduites pour les pneus. L'essai a été conduit par le département des autoroutes et des transports de la Saskatchewan dans la région du lac Big Quill, dans le sud de la province. Les véhicules employés durant l'essai ont été des trains routiers de type B à neuf essieux, des trains routiers de type B à huit essieux et des semi-remorques à six essieux. Les analyses statistique des données sur l'orniérage présentées dans cet article montrent que des pressions réduites pour les pneus peuvent de fait étendre la durée de vie de la chaussée pour des routes de gravier et à membrane mince. Sur les chaussées à membrane mince, il y a moins d'orniérage sur la voie employée avec des pneus à pression réduite jusqu'à ce que le traffic de véhicules soit deux fois plus élevé, et l'orniérage n'est pas plus mauvais sur la voie dédiée pour les pneus à pression réduite même lorsque le traffic de véhicules est dix fois plus élevé. Sur la surface de gravier, la profondeur des ornières est plus basse sur la voie pour les pneus à pression réduite jusqu'à ce que le traffic de camions soit deux plus élevé.Mots clés : orniérage, chaussée, gonflement de pneus central, pression de pneus, routes à volume réduit, routes non-pavées.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

There are a myriad of laws, regulations, and policies governing the operating weights and dimensions of trucks. In Canada and many northern states, these regulations form a continuum of basic limits, seasonal variations, and overweight/overdimension limits that are legally permitted. This paper deals with the seasonal aspects of weight limits (winter weight premiums and spring weight restrictions) governing trucking within and to and from the prairie region. This region encompasses Manitoba, Saskatchewan, and Alberta, and the northern tier states of Minnesota, North Dakota, and Montana. The paper presents results of research conducted for the transportation departments of the three prairie provinces and Public Works and Government Services Canada. It discusses existing winter weight premium and spring weight restriction regulations, as well as basic weight regulations in the region, and their technical rationale. It examines possibilities for using advanced technologies to help harmonize and rationalize seasonal truck size and weight regulations and enforcement practices, and identifies immediate opportunities for rationalization and harmonization of spring weight restrictions and winter weight premiums. [ABSTRACT FROM AUTHOR]

The new Canadian 24-Hour Movement Guidelines for Children and Youth emphasize the integration of all movement behaviours that occur over a whole day (i.e., light, moderate, and vigorous physical activity, sedentary behaviour, and sleep). These guidelines shift the paradigm away from considering each behaviour in isolation. This concept of the "whole day matters" not only calls for a change in thinking about movement but also for redevelopment of dissemination and implementation practice. Past guideline launch activities largely have aimed to create awareness through passive dissemination strategies (e.g., Website posts, distribution of print resources). For the integrated guidelines to have public health impact, we must move beyond dissemination and raising of awareness to implementation and behaviour change. Shifting this focus requires new, innovative approaches to intervention, including interdisciplinary collaboration, policy change, and refocused service provision. The purpose of this paper is to identify practitioners, professionals, and organizations with potential to disseminate and/or implement the guidelines, discuss possible implementation strategies for each of these groups, and describe the few resources being developed and those needed to support dissemination and implementation efforts. This discussion makes readily apparent the need for a well-funded, comprehensive, long-term dissemination, implementation, and evaluation plan to ensure uptake and activation of the guidelines. [ABSTRACT FROM AUTHOR]

In this paper, waste management in Alberta (AB) and British Columbia (BC) from 1996 to 2010 are examined with respect to generation characteristics and management efficiency. The daily average waste generation rates in AB and BC were 3.34 kg/capita and 2.50 kg/capita, respectively. It was found that annual family income has a positive relation with residential waste generation in both provinces, as did the proportion of educated citizens. Gross domestic product was positively related to non-residential waste generation in AB, and negatively related in BC. Annual agricultural farm cash receipts were positively related to non-residential waste generation in both provinces, and AB's industry earnings were significantly higher. Between 1998 and 2010, the average diversion rate in AB was 15.1%, and BC's was 32.9%, which place them on opposing sides of the national average (23.4%). Total operating expenditures were similar in both provinces, yet BC's waste diversion was more than double AB's. [ABSTRACT FROM AUTHOR]

Canada has two national civil codes of practice that include geotechnical design provisions: the National Building Code of Canada and the Canadian Highway Bridge Design Code. For structural designs, both of these codes have been employing a load and resistance factor format embedded within a limit states design framework since the mid-1970s. Unfortunately, limit states design in geotechnical engineering has been lagging well behind that in structural engineering for the simple fact that the ground is by far the most variable (and hence uncertain) of engineering materials. Although the first implementation of a geotechnical limit states design code appeared in Denmark in 1956, it was not until 1979 that the concept began to appear in Canadian design codes, i.e., in the Ontario Highway Bridge Design Code, which later became the Canadian Highway Bridge Design Code (CHBDC). The geotechnical design provisions in the CHBDC have evolved significantly since their inception in 1979. This paper describes the latest advances appearing in the CHBDC along with the steps taken to calibrate its recent geotechnical resistance and consequence factors. [ABSTRACT FROM AUTHOR]

This paper reviews annual government spending on Canadian agriculture that attempts to stabilize and enhance farm incomes. Over the past 5 years, 2/3 of the $3 billion spent on agriculture went into stabilization programs to support farm incomes. However, this level of support raises questions about the environmental consequences of enhanced agricultural production. Environmental impacts from agriculture are well known and addressed in US and EU policies. In contrast, Canadian government expenditures on environmental initiatives in agriculture, as a share of farm income, are more than 10 times smaller than those in the US and the EU. Nonetheless the evidence is that Canadian programs have modest impacts on production, but that chemical and fertilizer input use may be higher than in the absence of the program. One possible course of action is to introduce cross-compliance between program payments and environmental objectives. However, there are no requirements that Canadian producers receiving support comply with environmental standards. While cross-compliance could be considered in the Canadian context, policies that directly target specific environmental issues in agriculture may have greater impact. [ABSTRACT FROM AUTHOR]

This paper aims to be a cursory relative comparison between applications of custom-designed constructed wetland systems for specific water resources protection in Canada and northern China. Comparing constructed wetlands can be difficult and at times misleading; they are custom built to deal with specific target wastewater at specific locations and differ not only in physical shape and dimension, but in vegetation cover, hydraulic retention time, and pollutant loading rates. Treatment efficiencies defined by the Canadian and northern Chinese experience vary considerably. Experience in both countries shows that the majority of effluent values are generally better than those required by discharge standards in Canada and China. Examples provided from both countries demonstrated that plants can play a role in constructed wetland systems and make a difference in treatment efficiency. A review of the available case studies on cold weather treatment in both countries indicates that this technology is feasible in Canada and northern China, although further monitoring data are needed to optimize wetland design and ensure that the effluent quality standards are consistently met. Constructed wetland systems in both countries have an apparent advantage in construction costs, and the costs for treatment and operation and maintenance of these systems are much lower than those of conventional wastewater treatment plants. Land requirements for constructed wetlands present one of the factors most limiting their broader use, especially in China, where land resources are scarce and population density is high. [ABSTRACT FROM AUTHOR]

The last version of the National Building Code of Canada was issued in 2010. The next version will be issued in 2015. In the code cycle between 2010 and 2015 significant changes have taken place in the seismic design provision. The main factor that drives these changes is an improved understanding of the seismic hazard across the country. Changes have also been introduced in the site effect factors. The structural design provisions have been appropriately adjusted to respond to changes in the estimates of hazard and the new site effect factors. There are also new provisions related to design in regions of low hazard, buildings with flexible diaphragms, buildings with inclined columns, passive energy dissipation systems, base isolation, rocking foundations, glazing systems, racks, and elevators. Some of the changes are briefly discussed. The main focus of the paper is, however, on the revisions to the structural design provisions. [ABSTRACT FROM AUTHOR]

The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera, Curculionidae), a native insect of North America, periodically reaches population sizes that cause serious economic impact to the forest industry in western North America. The most recent outbreak in British Columbia (BC), Canada, which began in the late 1990s, is only now (2015) abating, after causing unprecedented tree mortality in lodgepole pine ( Pinus contorta Douglas ex. Loudon) forests. In this paper, we make use of permanent research plots to report on the condition of lodgepole pine forests in the Chilcotin Plateau of central BC, which underwent two fully documented mountain pine beetle outbreaks. In this region, the first outbreak started in the late 1970s and lasted until the mid-1980s; the second outbreak began in the early 2000s and ended in 2010. We measured the impacts of these outbreaks in terms of tree mortality and describe the characteristics of the legacies that remain following these outbreaks, including survivors in various canopy layers and levels of existing and new regeneration. We provide evidence in support of the existence of postdisturbance legacies that classify into five distinct stand structure types. Abundant regeneration and surviving intermediate canopy layers in most stands indicate that management actions to restock pine stands in this area will not likely be necessary. The information provided by this study is important for estimating future forest development and timber supply and for forest planning and management. [ABSTRACT FROM AUTHOR]

The article features scientist John Ripmeester, who has made enormous impact on various research areas involving nuclear magnetic resonance (NMR) spectroscopy, porous materials, and clathrate hydrates. Topics include Ripmeester's experience of working for the paper industry in Canada, how his interest in chemistry has been developed, and his retirement from research in 2008 to focus on his role as head of the Functional Materials Program of the Steacie Institute for Molecular Sciences (SIMS).

Fourteen large landslides have occurred within a 10 km stretch of the Thompson River Valley south of Ashcroft, British Columbia. The slides have had movements ranging from rapid (metres per hour) to very slow, and the largest slides have volumes approaching 15.0 × 106 m3. Investigations of these slides have been conducted since the early failures of the slopes were noted in the 1860s, and have continued with the periodic reactivations and slope movements since then. This paper focuses on the Ripley Slide, which is one of the slides within the Thompson River Valley. This slide is a very slow-moving landslide, which has recently been reactivated. This landslide is crossed by a major transportation corridor and has therefore been the subject of ongoing geotechnical investigation and instrumentation. The results of this investigation are interpreted in light of the wealth of accumulated knowledge from more than a century of geotechnical investigation within this valley. The data collected from the landslide show that, like other slow-moving landslides in this valley, the seasonal fluctuations of the Thompson River elevation strongly influence the instability and the rate of slope movement. Continuous global positioning system monitoring of the movement of the landslide combined with measurement of the pore pressures within the sliding mass and elevation of the river have allowed for an empirical correlation between the limit equilibrium method modelled factor of safety and the velocity of the landslide. [ABSTRACT FROM AUTHOR]

Government geological survey maps and research publications have portrayed the distribution of glacial landforms associated with the advance and retreat of the Laurentide and Cordilleran ice sheets across Alberta at a local, regional, and continental scale. To date, this information has not been systematically synthesized into a single compilation at a consistent scale. Although this original work provided valuable information to constrain reconstructions of former ice sheet extent, configuration, and flow geometry, its derivation primarily from the interpretation of aerial photographs and the Shuttle Radar Topography Mission 90 m digital elevation model (DEM) may result in methodological inconsistencies and spatial biases. These biases, together with challenges associated with geomorphic mapping in densely forested areas of western and northern Alberta limit the usefulness of previous mapping when applied to inversion-based ice sheet reconstructions, which have specific input data demands. Recently, light detection and ranging (LiDAR) DEMs have become increasingly available throughout Alberta. Hill-shaded imagery of these data provides unprecedented geomorphic detail beneath the forest cover and reveals that that the glacial geomorphology of northern and western Alberta is more complex than previously recognized. In this paper, we describe the methodology and geomorphic criteria used to produce a glacial landform map of Alberta using previously published data, supplemented by comprehensive new analysis of high-resolution (2-25 m) DEMs. These include 306 624 km2 of LiDAR imagery, with which it is now possible to verify and where necessary augment previous mapping, particularly across areas with a dense forest cover. [ABSTRACT FROM AUTHOR]

Much of Canada's terrestrial biodiversity is supported by boreal forests. Natural resource development in boreal forests poses risks to this biodiversity. This paper reviews the scientific literature to assess the effects of natural resource development on terrestrial biodiversity in Canadian boreal forests. We address four questions: (1) To what extent have Canadian boreal forests changed due to natural resource development? (2) How has biodiversity responded to these changes? (3) Will the biodiversity of second-growth forests converge with that of primary boreal forests? (4) Are we losing species from boreal forests? We focus on trees, understory plants, insects, fungi, selected mammals, and songbirds because these groups have been most studied. We review more than 600 studies and found that changes in community composition are prevalent in response to large-scale conversion of forest types, changes in stand structures and age distributions, and altered landscape structure resulting from forest management and habitat loss associated with other developments such as oil and gas, hydroelectric, and mining. The southern boreal forest has been more highly impacted than the north due to more extensive forest management and the cumulative effects of multiple forms of development. There is abundant evidence that most species are not in danger of being extirpated from the boreal forest due to these anthropogenic changes. A few species, including woodland caribou ( Rangifer tarandus) and grizzly bear ( Ursus arctos), have, however, undergone long-term range contractions. Significant gaps in our ability to assess the effects of natural resource development on biodiversity in the boreal zone are the lack of long-term spatial and population data to monitor the impact of forest changes on ecosystems and species. [ABSTRACT FROM AUTHOR]

Analyses of climate change and the forest sector have identified the importance of individual actors, institutions, and organizations within communities for effective adaption and climate mitigation. Yet, there remains little recognition of how the internal dynamics of these institutions and organizations are influenced by gender and other social considerations such as age and culture. Research from developing countries and cognate resource sectors suggests that these considerations are critical for enhancing local adaptive capacity. Despite extensive review of forestry research across North America and western Europe, we found almost no research that addresses how differential social capabilities within forest-based communities affect adaptation to climate change. In this paper, we document the potential that gender sensitivity might provide to conceptions and practical applications of adaptive capacity and identify four types of research opportunities to address this gap: ( i) developing disaggregated capitals frameworks; ( ii) creating inclusive models; ( iii) informing social planning; and ( iv) understanding gender mainstreaming. Research focused on these opportunities, among others, will provide more robust theoretical understanding of adaptive capacity and strategic interventions necessary for effective adaptation. [ABSTRACT FROM AUTHOR]

The first objective of this paper is to demonstrate how mathematical models simulating the structural state of sewer pipes can help to assess the financial resources required for the preservation of sewer networks. The second objective is to assess and compare the annual replacement rate that should be applied to four different Canadian sewer networks to stabilize their global structural state for the long term. The required annual replacement rates are similar for the four studied networks, even if their global structural states were different prior to replacement. Results also show that the required annual replacement rate is three times less if the deterioration states of all pipes in the network are known, as opposed to the case where the structural states are unknown. This demonstrates the importance of sewer pipe inspection for the planning of sewer pipe renewal. [ABSTRACT FROM AUTHOR]

There are concerns about the effect of increasing resource extraction and other human activities on the soils and vegetation of the boreal zone. The review covers published papers between 1974 and 2012 to assess the effects of natural disturbances and human activities on soils and tree nutrition and growth of the Canadian boreal zone. Changes in soil and foliar nutrients following disturbance were also analyzed by meta-analysis. When sufficient replicated studies were not available for a given disturbance or nutrient, response assessments or narrative summaries are presented. The majority of fertilization studies in the boreal zone showed a positive tree growth response to nitrogen (N) and phosphorus (P) fertilization either individually or in combination. Large amounts of N may be lost through volatilization following fire depending on the severity and frequency of the fire. This may contribute to N limitation in the boreal zone. Available soil P and extractable calcium (Ca) and magnesium (Mg) increased in the surface horizons following fire. In contrast, extractable P decreased following harvest. Harvesting had no effect on total or inorganic N except in mixedwoods where total N decreased in the surface organic horizon following harvest. These are potential areas of concern given tree growth responses to N and P fertilization. Potassium (K) in the forest floor did not change following fire or harvesting; thus, K availability for tree nutrition should not be at risk, since its cycle is rapidly restored. Mercury (Hg) cycling may be altered in the boreal zone as a result of flooding and if fire return intervals and intensities increase. Interactions of multiple disturbances may increase the risk of nutrient depletions, but there is currently little information on these interactions in the boreal zone. Evidence to date suggests the soils of the Canadian boreal zone have not been adversely affected except in localized areas. However, there is the risk of nutrient loss if soils are not considered in our forest management strategies, particularly where multiple disturbances may interact. The potential for off-site movement of nutrients and contaminants into the atmospheric and aquatic ecosystems, in addition to on-site environmental issues, is also a concern. [ABSTRACT FROM AUTHOR]

This paper presents the effectiveness of seven ground motion scaling methods and two spectral matching methods to achieve compatibility with the Canadian National Building Code (CNBC) 2005 uniform hazard spectrum for Montreal to perform nonlinear seismic analysis. Databases of 30 historical records and 30 Eastern North America simulated records have been selected to compute the reference mean seismic demand and its dispersion. The characteristics and destructive capacity of ground motions have been studied using a large number of indices computed from ( i) the records themselves, ( ii) a series of single degree of freedom structures, as well as ( iii) a four-story steel frame. Record scaling methods to the target spectrum using ( i) spectral intensity, ( ii) reducing the mean square error, ( iii) and minimizing dispersion as well as time domain spectral matching generated coherent seismic demand and dispersion in agreement with the reference values. Spectral matching to a specified elastic design spectrum does not reduce the dispersion of the nonlinear response. Therefore close spectral matching cannot be used to reduce the number of records to minimize the resources allocated in seismic safety assessment. At least seven records, as recommended in current CNBC and FEMA (2012) guidelines to compute an average response, should be used to characterize the nonlinear behaviour of structural systems. [ABSTRACT FROM AUTHOR]

John Tuzo Wilson (1908-1993) was one of the greatest Canadian scientists of the 20th century. His contributions to Earth Sciences, leading the formulation of the theory of plate tectonics, have revolutionized our understanding of how the planet Earth works and evolved over the past 4 billion years. This 50th anniversary special issue of the Canadian Journal of Earth Sciences is dedicated in honour of John Tuzo Wilson, who inspired tens of thousands of students all around the world to study the Earth. This special issue contains 12 papers dealing with various aspects of the 'Wilson Cycle' in the geologic record, plate tectonics, mantle plumes, and how John Tuzo Wilson accepted 'continental drift' and formulated the theory of plate tectonics. The contributions have mostly been made by geoscientists who directly or indirectly associated with John Tuzo Wilson and have contributed significantly to the plate tectonics paradigm. [ABSTRACT FROM AUTHOR]

The usage of recycled asphalt shingles (RAS) in hot mix asphalt (HMA) pavements provides many benefits as long as they are properly engineered into the various HMA mixes. Contractors, consultants, and Departments of Transportation have evaluated the performance of these various materials, although they are still only used in a limited number of areas. Alternatively, recycled asphalt pavement (RAP) is recognized as a high value recycled material and is actually the most recycled material in North America. In Ontario, RAP is successfully used in most HMA. Related studies on HMA containing RAS and RAP are limited in Canada although recently studies and field trials on effectively using RAS in HMA in Ontario have been completed by the Centre of Pavement and Transportation Technology (CPATT) at University of Waterloo in partnership with Miller Paving Ltd and the Ontario Centre of Excellence. This paper presents key findings from a comprehensive laboratory investigation and analysis of six asphalt mixes with RAS and RAP in Ontario through dynamic modulus, resilient modulus, thermal stress restrained specimen, and flexural fatigue testing. Using RAS alone or combining with RAP makes the asphalt stiffer at high and low temperatures respectively. Lowering the low temperature performance grade of the asphalt binder by 6 °C and incorporating 3% RAS or less with RAP in HMA mix design can result in meeting the appropriate specification. While field testing of RAS pavements demonstrated that surface friction properties are in good condition in various environmental and loading conditions, the laboratory test results and field performances indicate that RAS can be a useful additive to asphalt mixes in Ontario hot mix pavement through reasonable mix design. [ABSTRACT FROM AUTHOR]

Mine developments, such as haulage drifts, cross-cuts, and intersections, are the only way to access valuable ore from mining zones; they link mine developments with the nearest ore access points. Thus, they must remain stable throughout their service life or production plan. Mine development instability can cause production delay, loss of reserves, as well as damage to equipment and injury to miners. This paper presents a stepwise methodology to assess the stability of mine development intersections with respect to the mine production plan. A case study, the #1 Shear East orebody at Vale Garson Mine in Sudbury, Ontario, is presented. A three-dimensional, elastoplastic, finite difference model (FLAC 3D) is created to simulate the development of an intersection situated 1.5 km below ground surface. The unsatisfactory performance of the intersection is evaluated in terms of strength-to-stress ratio with respect to mining sequence. A failure criterion is defined by a minimum strength-to-stress ratio of 1.4, and is used for mine developments (temporary openings). The intersection stability is evaluated at various mining stages and the modified 'point-estimate method' (PEM) of (2 n2 + 1) is then invoked to study the probability of drift instability at the intersection. The results are presented and categorized with respect to probability, instability, and mining stage. [ABSTRACT FROM AUTHOR]

Conservation efforts to sustain water resources and aquatic biodiversity in boreal watersheds will require reliable information on the recent status of various indicator species and an improved understanding of the risks to aquatic biodiversity posed by resource development activities. We reviewed the recent state of knowledge on the responses of aquatic biodiversity to forest management, pulp and paper mill effluents, hydroelectric impoundments, mining of minerals and metals, oil sands extractions, and peat mining and offer a prognosis for aquatic biodiversity under each of these environmental stressors. Despite the prevalence of natural resource development in Canada's largest forest ecosystem, there was a limited amount of published literature on the effects of many of the disturbance types on various indicators of aquatic biodiversity, making it difficult to produce a current and reliable status assessment. Across most of the boreal zone, there is a lack of coordinated, consistent data collection for many of the bioindicators and disturbance types discussed in this review. Forecasting the future state of aquatic biodiversity across the boreal zone is challenged by increasing natural resource development and its interactions with other stressors, especially climate change. The cumulative effects of multiple stressors coupled with resource development activities in boreal watersheds remain largely unknown. More importantly, the ecological thresholds for these cumulative effects (that is, the point at which aquatic ecosystems and their biodiversity cannot recover to a desired state within a reasonable time frame) are also unknown and remain gaps in our knowledge. The recent literature identifies a number of risks to aquatic biodiversity at local (tens of square kilometres) to regional (hundreds of square kilometres) scales associated with natural resource development. There are indications that many of these risks can be minimized by 'greener' technologies for resource development and reclamation, practical conservation planning and regulation, and increased stewardship in watershed management, although the effectiveness of many of these measures cannot yet be assessed from the published literature. [ABSTRACT FROM AUTHOR]

This Special volume published by the Canadian Journal of Earth Sciences consists of a collection of six papers on the petrology, geochemistry, and metallogeny of igneous rocks emplaced in large igneous provinces (LIPs). The papers provide a snapshot of results presented at a Special Session of the 2017 Geological Association of Canada – Mineral Association of Canada Joint Annual Meeting held in Kingston, Ontario, by members of the vibrant geoscience community dedicated to the study of LIPs. Participants applauded the idea of a joint session on these topics and as a result, the session fostered animated discussions and new collaborations. The scope of magmatic and metallogenic studies of LIPs often precludes the type of brainstorming that took place during the meeting. This Special volume demonstrates that a robust understanding of magmatic processes represents the essential first step towards the search for mineral deposits in LIPs worldwide. [ABSTRACT FROM AUTHOR]

Reported from marine, freshwater, and terrestrial habitats, trichomycetes are an ecological group of both fungi and protists that colonize the guts of insects, crustaceans, and millipedes. Lotic sites (streams, rivers) are a rich source of hosts and their trichomycetes. As part of a larger study of trichomycetes from different aquatic habitats within the Halifax Regional Municipality in Nova Scotia, Canada, one stream from each of three separate watersheds was sampled for aquatic insects, and their guts were dissected and examined for microscopic trichomycetes. Over the course of 17 months, 24 species of trichomycetes were collected including the following four new species: Glotzia gemina sp. nov. R.T. William and Strongman from a mayfly (Baetidae); Stachylina tanysoma sp. nov. R.T. William and Strongman; Smittium ampliboja sp. nov. R.T. William and Strongman; and Smittium insolitum sp. nov. R.T. William and Strongman, all recovered from dipteran (Chironomidae) hosts. New continental records were established for three species including Smittium pusillum Manier & Coste and Stachylina euthena Manier & Coste, both originally described from France, and Smittium nodifixum Strongman & Shengquan Xu previously known only from China. A new regional geographical record for Pennella arctica Lichtw. & M.C. Williams is reported and 17 other species previously known from eastern Canada were recorded. Pteromaktron timberleaense R.T. William & Strongman was described by us from Timberlea, Nova Scotia, but at the time no sexual spores (zygospores) were seen. In the collections reported in this paper, zygospores were found so the original description is emended to include the zygospore features for this species. This report adds to the published data on trichomycetes from Nova Scotia that have appeared over the last 10 years and highlights the significance of long-term sampling in cataloguing the diversity of this group of insect associated microorganisms. We also present some data on seasonal variation in trichomycete occurrence and comment on site specificity in the trichomycetes we collected. [ABSTRACT FROM AUTHOR]

In this paper, the seismic performance of 1970s regular R/C bridge is investigated in terms of ductility demand, considering site-specific time histories and the amplification effect of soil with heterogeneous stratigraphy. The five seismic site classes of the 2005 National Building Code of Canada were used in this study and seismic site analyses were performed on soil columns representing real stratigraphies of typical Quebec City soil profiles. A total of 24 linear modal dynamic analyses and 24 nonlinear time-history analyses were performed using historical earthquakes representative of Eastern Canada. It was found that the bridge model shows yielding at the base of the columns for site classes C, D, and E. For site classes D and E the 2005 NBCC amplification factors were found to underestimate the amplification effect on the bridge's response. These results also show that the energy dissipation is a better indicator of damages than the permanent displacement. [ABSTRACT FROM AUTHOR]

Epigenetics is revealing how “nature is nurtured”, with environmental factors such as nutrition, environmental neurotoxicants, and psychological stress influencing DNA expression. In this current opinion paper, we argue that understanding the dynamic interplay between the genome acquired at conception and environmental exposures throughout life requires pregnancy and birth cohorts, and that greater Canadian national commitment to the infrastructure needed for sustaining such cohorts is warranted. We present a framework that is now being implemented in Alberta. [ABSTRACT FROM AUTHOR]

As the forest products industry evolves into a modern industry based on cutting-edge industrial and management research, the prevalence and importance of university research centres have gained importance. Although there has been increased funding and attention given to university-industry research centres from policy makers and researchers, little is still known about the benefits or value that these collaborations provide and create for firms. Applied academic research requires the active participation of researchers and practitioners. In the Canadian forest products industry, there are other important actors that need to be considered, the federal and provincial governments as owners and regulators of the resource and funders of research and development projects and intermediary organisations who are often charged with transforming academic results into tools and methods able to be implemented into industry firms. This paper presents the results of three comparative case studies of university-industry research centres operating in the Canadian forest products industry through an exploration of their knowledge and technology transfer processes. The goal is to better understand the value that has been created for the four main groups of actors involved though informal and formal transfer processes and which processes are best suited for different types of knowledge. [ABSTRACT FROM AUTHOR]

To improve construction productivity and performance, it must be measured. The Construction Sector Council (CSC) has started a Labour Productivity and Project Performance Benchmarking Program for the infrastructure sector of the construction industry in Canada. Metrics were developed for project cost, time, safety, and quality performance; labour productivity; rework; project conditions; and management practices related to health and safety. Data from 19 projects located in different regions of Canada were collected and analyzed. Based on the results and on industry feedback, additional metrics for practices related to project planning, materials management, and construction supervisory skills development were developed. This paper describes the development of the program. Lessons learned during the development and implementation of the benchmarking and metrics program are summarized and steps to establish a sustainable program are identified. It is concluded that a successful program is feasible and has the potential to have broad impact. [ABSTRACT FROM AUTHOR]

Smart card fare collection systems for public transit produce a huge quantity of data on a daily basis. The ability to follow the use of a single card throughout the months gives the opportunity of measuring the loyalty of the individual to the service. Then, operators can have quantitative knowledge of the loyalty in their network. However, it is also important to know what are the factors that influence the survival of the users. This paper presents the application of a discrete time hazard model to 5 years of data of a medium-size transit authority in Canada. The concept of the hazard model relates to the fact that the probability to continue the use of a smart card by user i, at time t, is conditional to the probability of not cancelling the card before the time period. Hence, its use is appropriate in this case. Results for the regular adult fare show that loyalty is positively influenced by residential density and by the transit share in the area. A younger population will also be retained longer in the system. However, a high unemployment rate has a negative impact on survival. A high share of transit and walk trips is also affecting the loyalty, suggesting that the retention is reduced when there are more mode choices available to the commuter. [ABSTRACT FROM AUTHOR]

Pervious concrete pavement offers sustainable solutions to urban growth challenges by providing a stormwater management alternative and benefits to the ecosystem and community. Maintenance may not always be required but is likely needed in general to maintain adequate performance of pervious concrete. A Canada wide study has been initiated to evaluate the performance of pervious concrete pavement in the Canadian freeze-thaw climate. This paper presents the results to date related to the work that has been performed in evaluating maintenance methods at five field sites across Canada. In general, the results indicate that it is essential to agitate the debris in the voids to remove and clear as much material as possible. The maintenance methods that have been evaluated are the following: sweeping using a broom or street sweeper; rinsing the surface with a garden hose or large hose; vacuuming; and power washing. [ABSTRACT FROM AUTHOR]

No net loss of productive capacity (PC) of fish habitat has been the central concept guiding Canadian fish habitat management policy since 1986. The purpose of this paper is to describe the concept of PC, to review the history and application of the fish habitat management policy in Canada, and to provide a critical review of the range of potential approaches to estimating PC. The approaches were grouped by their central focus: habitat, individual, population, and community-ecosystem. A set of case studies is used to illustrate the use of some approaches drawn from freshwater and marine contexts. Ten components to assessing no net loss of PC were developed and used in the review of approaches for evaluating potential limitations. The review also highlighted the likely future direction of method development, with increasing emphasis on dynamic models integrating population responses to habitat supply characteristics. More work needs to be done to turn research-based metrics of PC into practical operational management assessment tools and to better quantify the link between habitat structure and function and fisheries productivity. The evolving approaches to measure PC reinforce the ties that fish habitat management has to the emerging practices in ecosystem-based management. [ABSTRACT FROM AUTHOR]

In several processes of the forest products industry, an in-depth knowledge of log and board internal features is required and their determination needs fast scanning systems. One of the possible technologies is X-ray computed tomography (CT) technology. Our paper reviews applications of this technology in wood density measurements, in wood moisture content monitoring, and in locating internal log features that include pith, sapwood, heartwood, knots, and other defects. Annual growth ring measurements are more problematic to be detected on CT images because of the low spatial resolution of the images used. For log feature identification, our review shows that the feed-forward back-propagation artificial neural network is the most efficient CT image processing method. There are also some studies attempting to reconstruct three-dimensional log or board images from two-dimensional CT images. Several industrial prototypes have been developed because medical CT scanners were shown to be inappropriate for the wood industry. Because of the high cost of X-ray CT scanner equipment, other types of inexpensive sensors should also be investigated, such as electric resistivity tomography and microwaves. It also appears that the best approach uses various different sensors, each of them having its own strengths and weaknesses. [ABSTRACT FROM AUTHOR]

Geotechnical input to the design, construction, and operations of pipelines in permafrost may differ significantly from that for pipelines in temperate terrain. The general remoteness and terrain fragility of permafrost regions are key issues that challenge the geotechnical input. Specific geotechnical issues that necessitate input include pipeline routing, slope stability, thaw settlement and frost heave, ditching, buoyancy control, upheaval buckling. and others. This paper examines the history of pipeline development in Canada north of the 60th latitude and highlights some key design issues and some of the technical developments over the past 40 years of design, construction, and operations of pipelines in permafrost regions. Advances have been made in areas such as geothermal modeling, slope stability assessments, terrain mapping technologies, thaw settlement and frost heave prediction, and predicting and monitoring pipeline strain demand. [ABSTRACT FROM AUTHOR]

The purpose of this paper was to report the physical activity and health outcomes results from the Physical Activity Counselling (PAC) trial. Patients ( n = 120, mean age 47.3 ± 11.1 years, 69.2% female) who reported less than 150 min of physical activity per week were recruited from a large community-based Canadian primary care practice. After receiving brief physical activity counselling from their provider, they were randomized to receive 6 additional patient-centered counselling sessions over 3 months from a physical activity counsellor (intensive-counselling group; n = 61), or no further intervention (brief-counselling group; n = 59). Physical activity (self-reported and accelerometer) was measured every 6 weeks up to 25 weeks (12 weeks postintervention). Quality of life was also assessed, and physical and metabolic outcomes were evaluated in a randomly selected subset of patients (33%). In the intent-to-treat analyses of covariance, the intensive-counselling group self-reported significantly higher levels of physical activity at 6 weeks ( p = 0.009) and 13 weeks ( p = 0.01). There were no differences in self-reported physical activity between the groups after the intervention in the follow-up period, nor was there any increase in accelerometer-measured physical activity. Finally, the intensive-counselling patients showed greater decreases in percent body fat and total fat mass from 13 weeks to 25 weeks. Results for physical activity depended on the method used, with positive short-term results with self-report and no effects with the accelerometers. Between-group differences were found for body composition in that the intensive-counselling patients decreased more. A multisite randomized controlled trial with a longer intensive intervention and follow-up is warranted. [ABSTRACT FROM AUTHOR]

In this study, the equation for the punching shear strength prescribed in the Canadian code is evaluated based on a database of experimental results. This paper also includes a discussion of the effect of several parameters on the punching shear strength in the Canadian and European codes. The experimental work presented includes testing of ten full-scale two-way slabs with different reinforcement ratios to examine the effect of reinforcement ratio on punching shear capacity. A simplified practical punching shear equation is also proposed based on statistical analysis of experimental results from the database. Statistical regression analysis is conducted on 190 test data available in the literature to evaluate the influence of reinforcement ratio on punching shear strength. The proposed equation accounts for the effect of slab depth using fracture mechanics concepts. The analytical study showed that the reinforcement ratio has a strong influence on punching shear strength. The proposed equation could be an alternative to the current punching shear equation used by Canadian Standards Association CSA-A23.3-04 design code. [ABSTRACT FROM AUTHOR]

Source water protection (SWP) is the most important step in the implementation of a multi-barrier approach that ensures cost-effective delivery of safe drinking water. However, implementing SWP strategies can be a challenging task owing to technical and administrative issues. Decision support tools for effective implementation of SWP strategies can be very helpful that may lead to saving time and resources. This paper critically reviews different SWP strategies available for surface waters and also discusses various formulations for water quality assessment at the source. Source water quality regulations in Canada and other jurisdictions around the world are also discussed. Stormwater management ponds, vegetated filter strips, pollution control by effective agricultural practice (e.g., cover crop and crop rotation) and fencing are found to be frequently mentioned in those regulations. These strategies are discussed in details in terms of their key features to achieve the highest possible removal efficiencies for selected water quality parameters. Finally, a conceptual model is proposed to evaluate water quality changes at the source based on selected source water protection strategies. The model uses SWP strategies as a means to reduce possible pollutants in the source water. It also utilizes simple mass balance equations (dilution) to estimate the concentrations in the receiving water bodies and does not consider physico-chemical and other reactions. A surrogate measure, water quality index (WQI), based on selected water quality parameters, is used for the assessment of source water quality. [ABSTRACT FROM AUTHOR]

The Thompson Nickel Belt marks the boundary between the Archean Superior Province and the Trans-Hudson Orogen in Canada. It comprises Archean gneisses, and Paleoproterozoic rocks with metasediments and metavolcanites (Ospwagan Group) and intrusions. The gneisses are frequently migmatitic and host numerous pegmatites. The western belt boundary is a fault contact with the Kisseynew Domain of the Reindeer Zone. In the south, the transition zone between the belt and the Kisseynew Domain comprises granitoids and a detrital sequence (Grass River Group), part of which grades into turbidites in the Kisseynew Domain. The eastern belt boundary is a diffuse zone where the Archean east-west (E-W) structural trend changes into the north-northeast (NNE) trend of the belt. This paper presents U-Pb ages for granitoids and 207Pb/206Pb detrital zircon ages from the Ospwagan and Grass River groups. Ages and a comparison of events in the belt and in the eastern Reindeer Zone have major implications. The change from stable platform deposits to syn-tectonic filling and emplacement of mafic intrusions in the Ospwagan Group are attributed to the convergence between the Reindeer Zone and the Superior Province at 1891-1885 Ma. At ca. 1850 Ma, continuing convergence led to drowning of marginal basins of the Superior craton and to the development of a transpressive regime in the belt, the onset of which could be as old as ca. 1885 Ma. Metamorphic ages of 1818-1785 record closure of the Kisseynew basin and crustal thickening. Collision of the new continental block with the Superior Province was accommodated by transpression until 1750-1720 Ma. La ceinture de Thompson est située entre le Craton archéen du Supérieur et l'orogène paléoprotérozoïque du Trans-Hudson, au Canada. Elle comprend des gneiss archéens souvent migmatitiques, et des roches paléoprotéroïques, métasédiments et métavolcanites (Groupe Ospwagan), et intrusions. A l'ouest, une zone de faille marque le contact entre la ceinture et le domaine Kisseynew de la Zone de Reindeer. Vers le sud, cette zone de transition entre la ceinture et le domaine Kisseynew comprends des granitoïdes et une séquence détritique (Groupe Grass River), qui passe graduellement aux turbidites du domaine Kisseynew. Sur la bordure orientale de la ceinture, le grain structural E-W du Craton archéen se réoriente dans le grain NNE de la ceinture. Cet article présente des âges U-Pb pour différents granitoïdes et des âges 207Pb/206Pb pour les zircons détritiques des groupes Ospwagan et Grass River. Les âges et une comparaison des événements affectant la ceinture et l'est de la zone Reindeer ont des implications importantes. Dans le groupe Ospwagan, le passage de dépôts de type plate-forme à des dépôts syn-tectoniques, et l'intrusion de roches basiques, sont attribuées à la convergence entre la zone Reindeer et le Craton du Supérieur vers 1891-1885 Ma. Vers 1850 Ma, la convergence conduit à l'enfouissement des bassins de la marge du Craton et à un régime transpressif pouvant avoir débuté dès ca. 1885 Ma. La fermeture du bassin de Kisseynew et l'épaississement crustal sont enregistrés par des âges de métamorphisme entre 1818 et 1785 Ma. Le régime transpressif se poursuit jusqu'à ca. 1750-1720 Ma. [ABSTRACT FROM AUTHOR]

As many insect outbreak reconstructions are typically based on targeted single-site sampling, researchers have often been limited in their ability to draw conclusions about regional trends as opposed to local trends in the data. The results of this paper demonstrate the value of a systematic sampling design when studying spatio-temporal processes that can vary greatly within large continuous areas of forest. Many single-site research programs have been conducted to reconstruct the history of larch sawfly (Pristiphora erichsonii Htg.) outbreaks in the eastern boreal region of North America. However, no such research has yet been conducted in the region of Labrador. In an attempt to illustrate the strength of a systematic gridded sampling protocol over a single-site study, we sampled a 12-site grid in western Labrador. Dominant and codominant species were sampled at each grid point, resulting in 24 master chronologies. Six eastern larch (Larix laricina (Du Roi) K. Koch) chronologies (host) and a regional black spruce (Picea mariana (Mill.) Britton, Sterns, Poggenb.) chronology (nonhost) were used to establish a host–nonhost analysis of past sawfly outbreaks on a regional scale. Both regional and localized larch sawfly outbreaks were identified, but in general, larch sawfly outbreaks in western Labrador appeared to be spatially synchronous and regional in scale. [ABSTRACT FROM AUTHOR]

This paper presents an assessment of the seismic performance of a ductile concrete core wall used as a seismic force resisting system for a 12-storey concrete office building in Montréal, designed according to the 2005 National building code of Canada (NBCC) and the 2004 Canadian Standards Association standard A23.3. The core wall consists of a cantilever wall system in one direction and a coupled wall system in the orthogonal direction. The building is analyzed in the nonlinear regime. The main conclusion from this work is that the capacity design shear envelope for the studied wall structure largely underestimates that predicted, primarily in the cantilever wall direction, and this in turn significantly increases the risk of shear failure. This issue is essentially due to (i) an underestimation by the new NBCC spectral response acceleration of the higher mode responses of a reinforced concrete wall structure whose seismic response is dominated by higher modes; and (ii) a deficiency in the capacity design method in estimating the wall shear demand on such walls, even when their behavior is lightly inelastic. [ABSTRACT FROM AUTHOR]

Northern communities often have limited resources to resolve petroleum hydrocarbon (PHC) contamination. This project investigated an innovative approach for the management of diesel-contaminated soil in a remote community in Labrador. The soil was first treated in a passively aerated biopile to reduce the concentrations of mobile PHCs. The treated soil was then disposed of in the local landfill. Maximum total petroleum hydrocarbon (TPH) concentrations in soil, concentrations of PHCs with less than 16 carbons in soil, and TPH in leachate decreased during the 1 year field treatment. Microcosms incubated at 7 and 22 °C in the laboratory showed the potential for biodegradation of the PHCs. However, volatilization was likely the predominant PHC removal mechanism in the field. Disposal of treated soil to landfills has the advantage of transforming waste (i.e., soil) into a valued product (i.e., cover for the refuse). The development of risk-based guidelines for the disposal of PHC-contaminated soil into landfills in Canada appears to be needed and is discussed in this paper. Guidelines should be protective of the environment while prevent over-treatment of the soil, which may result in unnecessary spending and environmental impacts. The cost of the system tested was compared to that of treating soil in an off-site facility. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to evaluate whether future climate change would trigger an increase in the fire activity of the Waswanipi area, central Quebec. First, we used regression analyses to model the historical (1973–2002) link between weather conditions and fire activity. Then, we calculated Fire Weather Index system components using 1961–2100 daily weather variables from the Canadian Regional Climate Model for the A2 climate change scenario. We tested linear trends in 1961–2100 fire activity and calculated rates of change in fire activity between 1975–2005, 2030–2060, and 2070–2100. Our results suggest that the August fire risk would double (+110%) for 2100, while the May fire risk would slightly decrease (–20%), moving the fire season peak later in the season. Future climate change would trigger weather conditions more favourable to forest fires and a slight increase in regional fire activity (+7%). While considering this long-term increase, interannual variations of fire activity remain a major challenge for the development of sustainable forest management. [ABSTRACT FROM AUTHOR]

The boreal forest of higher latitudes constitutes a reservoir of trees of great ecological importance and unknown economic potential, but the stand dynamics in these regions still remain essentially unexplored. This paper examines the change in age and size structures during stand development on the northern border of the natural closed boreal forest in Quebec, Canada. Height, diameter, and age of trees were measured in 18 plots with stand ages between 77 and 340 years. The occurrence, size, and origin (layer or seed) of seedlings and saplings were assessed in subplots. Tree density ranged from 600 to 3750 trees·ha–1. Picea mariana (Mill.) BSP was the dominant species, mainly originating by layering. A cluster analysis segregated plots into even-aged and uneven-aged stands according to tree age, but size distribution of trees, saplings, and seedlings did not differ statistically between the two groups. Even-aged stands exhibited a 60% probability of assuming an uneven-aged structure between 120 and 200 years after stand initiation. At high latitudes, the closed boreal forest of P. mariana appears homogeneously sized, with similar distributions of diameter and height across all stages of stand development. [ABSTRACT FROM AUTHOR]

In Canada, the piggery industry is an essential part of the agricultural sector, but the main waste product of this industry, swine slurry, is particularly harmful to the environment. The anaerobic storage conditions and the excessive use of slurry for agricultural fertilization contribute, respectively, to the emission of greenhouse gases and to aquatic pollution. This paper provides a review of these environmental concerns and of the existing mitigation technologies. Water pollution from swine slurry is associated with the nutrients it contains, such as nitrogen and phosphorous, while the main greenhouse gases produced by the piggery industry are methane and nitrous oxide. Available technologies can valorize the slurry through agricultural fertilization, reduce greenhouse gas emissions, by limiting nutrient availability for example, or treat the effluents using solid-liquid separation, flaring or biological processes. Specific attention is paid to biofiltration due to its potential to simultaneously treat these two types of pollution. [ABSTRACT FROM AUTHOR]

Groundwater plays a major role in social and economic development and in human and ecosystem health. However, little is known about the potential impacts of climate change on this resource in Canada, namely if groundwater recharge is increasing or decreasing over time. This paper focuses on trend statistical analysis of historical series of baseflow and groundwater levels and their field significance as indicators of recharge. Monitoring wells are mainly located in the southern half of western Canada, where few gauging stations either are available or provide significant trends. Both data sets are thus complementary. Results show that most available groundwater level series have significant trends (80%), whereas most available baseflow series have not (3%–33%). However, groundwater level series usually show smaller slope magnitudes than baseflow series. Mixed trends are often observed across Canada for a given variable, period, or series length, although some regions can have marked trends. For instance, values below the 55°N latitude, and especially values in Atlantic Canada, show mostly downward trends (decreasing recharge). Values north of the 55° parallel often show upward trends. All groundwater level results are field significant at the 10% level, versus only 35% for baseflow results, but they show mixed results. Baseflow values show a majority of downward trends for annual values and the summer period for 40- and 50-year series, thus showing field significance, whereas mixed results are observed for 30-year series and the spring, fall, and winter seasons. [ABSTRACT FROM AUTHOR]

The state-of-the-art of sediment source identification is reviewed in this paper. Sediment “fingerprinting” techniques using different “fingerprint” properties were examined. With these techniques, it is possible to identify potential sources of sediment transported in river systems. Such knowledge is useful for implementing sediment control strategies to limit sediment production from upland areas in a watershed as well as for developing guidelines for land use practices to minimize adverse impacts on surface and ground water resources in agricultural watersheds. Examples of sediment source identification techniques that were carried out in agricultural watersheds in different parts of the world were also included in the present review. [ABSTRACT FROM AUTHOR]

Because of changes in functional or security requirements, many new or existing buildings are now required to resist blast loads. New buildings can be designed and constructed to resist defined blast loads. Existing buildings, on the other hand, would have to rely on a risk assessment to determine both its vulnerability to blast effects and the necessary measures to mitigate the unacceptable blast effects. A rapid screening methodology has been developed for conducting a preliminary assessment of buildings against external blast effects. The methodology accounts for the threat, the vulnerability of the building, the consequence of an event and the risk, which is the product of the threat and the consequence. The rapid screening methodology has been applied to several buildings and the results are reasonable. This paper presents the rapid screening methodology and its application to two federal buildings in Canada. [ABSTRACT FROM AUTHOR]

Single-storey braced steel frame buildings (SSBSFs) are currently the most widely used commercial structures, which include strip malls, power centres, warehouses, small and medium-sized industrial plants. The lateral seismic or wind forces acting on such low-rise structures are usually transferred from a metal roof-deck diaphragm to a system of vertical bracing members. Because these flexible roof diaphragms have a considerable effect on the dynamic response of SSBSFs during an earthquake, they also play an important role in the evaluation of the fundamental vibration period, a key parameter in determining the magnitude of the design seismic forces. It is therefore of utmost importance to reliably predict the fundamental period of SSBSFs. This paper presents the results of a four-year field measurement research project on the dynamic behaviour of SSBSFs. The goal of the project was to create a reliable database for the dynamic characteristics of SSBSFs (periods, mode shapes, and damping) and to find a relationship between them and the geometric parameters (height and plan dimensions). The field tests are described, along with the selected buildings and experimental setup. The measured fundamental periods are then compared to the National building code of Canada (NBCC) empirical equations. A statistical analysis of the data, based on different regression models, yielded new proposed building geometric parameters to be used in simple equations for the prediction of the fundamental period of SSBSFs. [ABSTRACT FROM AUTHOR]

Dumping has been one of the most controversial issues in the never-ending softwood lumber trade dispute between the United States (US) and Canada. In this paper, we investigate whether the softwood lumber producers in Ontario dumped product into their major market in the US during the period from April 1996 to September 2006. The Enhanced Parity Bounds Model was used to explore the possibility that Ontario’s softwood lumber producers had exercised price discrimination between the Toronto market and the Great Lakes market. Our analysis indicates that the industry had on average charged a higher price in the Great Lakes market than in the Toronto market during this period. Based on this evidence and the economic conditions in which a US antidumping investigation and two administrative reviews were conducted, we draw the conclusion that the Ontario’s softwood lumber producers did not dump product into the US market during the study period. [ABSTRACT FROM AUTHOR]