Search

Diameter at breast height (DBH) is a unique attribute used to characterize forest growth and development for forest management planning and to understand forest ecology. Forest managers require an array of DBHs of forest stands, which can be reconstructed using selected probability distribution functions (PDFs). However, there is a lack of practices that fit PDFs of sub-dominating species grown in natural mixed forests. This study aimed to fit PDFs and develop predictive models for PDF parameters, so that the predicted distribution would represent dynamic forest structures and compositions in mixed forest stands. We fitted three of the simplest forms of PDFs, log-normal, gamma, and Weibull, for the DBH of eight tree species, namely balsam fir (Abies balsamea [L.] Mill.), eastern white pine (Pinus strobus L.), paper birch (Betula papyrifera Marshall), red maple (Acer rubrum L.), red pine (Pinus resinosa Aiton), sugar maple (Acer saccharum Marshall), trembling aspen (Populus tremuloides Michx), and white spruce (Picea glauca [Moench] Voss), all grown in natural-origin mixed forests in Ontario province, Canada. We estimated the parameters of the PDFs as a function of DBH mean and standard deviation for these species. Our results showed that log-normal fit the best among the three PDFs. We demonstrated that the predictive model could estimate the recovered parameters unbiasedly for all species, which can be used to reconstruct the DBH distributions of these tree species. In addition to prediction, the cross-validated R2 for the DBH mean ranged between 0.76 for red maple and 0.92 for red pine. However, the R2 for the regression of the standard deviation ranged between 0.00 for red pine and 0.69 for sugar maple, although it produced unbiased predictions and a small mean absolute bias. As these mean and standard deviations are regressed with dynamic covariates (such as stem density and stand basal area), in addition to climate and static geographic variables, the predicted DBH distribution can reflect change over time in response to management or any type of disturbance in the regime of the given geography. The predictive model-based DBH distributions can be applied to the design of appropriate silviculture systems for forest management planning. [ABSTRACT FROM AUTHOR]

Methane flux measurements were carried out at a temperate forest (Haliburton Forest and Wildlife Reserve) in central Ontario (45° 170' 11" N, 78° 32' 19" W) from June-October, 2011. Continuous measurements were made by an off-axis integrated cavity output spectrometer Fast Greenhouse Gas Analyzer (FGGA) from Los Gatos Research Inc. that measures methane (CH4) at 10 Hz sampling rates. Fluxes were calculated from the gas measurements in conjunction with wind data collected by a 3-D sonic anemometer using the eddy covariance (EC) method. Observed methane fluxes showed net uptake of CH4 over the measurement period with an average uptake flux (± standard deviation of the mean) of -2.7±0.13 nmolm-2 s-1. Methane fluxes showed a seasonal progression with average rates of uptake increasing from June through September and remaining high in October. This pattern was consistent with a decreasing trend in soil moisture content at the monthly time scale. On the diurnal timescale, there was evidence of increased uptake during the day, when the mid-canopy wind speed was at a maximum. These patterns suggest that substrate supply of CH4 and oxygen to methanotrophs, and in certain cases hypoxic soil conditions supporting methanogenesis in low-slope areas, drive the observed variability in fluxes. A network of soil static chambers used at the tower site showed close agreement with the eddy covariance flux measurements. This suggests that soil-level microbial processes, and not abiological leaf-level CH4 production, drive overall CH4 dynamics in temperate forest ecosystems such as Haliburton Forest. [ABSTRACT FROM AUTHOR]

Canada has 347 million ha of forest cover, contributing to the potential large availability of wood‐based resources. Although Canada's forest sector contributed $23.7 billion to the national nominal gross domestic product (GDP) in 2019, the GDP contribution of the wood product manufacturing subsector shrank by 6%. To reposition the Canadian forest industry, new forest management practices and wood‐based conversion technologies should be applied. In this context, the use of woody biomass in biorefineries to produce clean energy, fuels, and chemicals is becoming increasingly significant. There is a need to understand the current status and challenges of the wood‐based biomass conversion technologies that have been and are being developed in Canada. This information will help decision‐makers in formulating and implementing forest sector‐related policies for a sustainable bioeconomy in Canada. This study is focused on a review of Canadian woody biomass conversion technologies. Our critical review identified considerable potential biomass conversion technologies specialized for woody feedstock, all in the Canadian setting. We focused on the prospects of revitalizing Canada's pulp and paper industry through the integration of pre‐treatment processes and biochemical technologies. The thermochemical conversion pathway was identified as the dominant route for woody feedstock valorization. The review also identified pathways with the potential to diversify the existing product mix that generate products from wood streams, such as chemicals and biomaterials. Most of the biochemical and thermochemical research done in institutional and multi‐institutional research collaborations from laboratory scale to industrial scale will boost the chances of the commercialization of a wood‐based biorefinery in Canada. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Reviews is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Environmental Reviews is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ongoing COVID-19 pandemic has disrupted global economic activity in all sectors, including forest industries. Changes in demand for forest products in North America over the course of the pandemic have affected both primary processors and downstream industries reliant on residues, including wood pellet producers. Wood pellets have become an internationally traded good, mostly as a substitute for coal in electricity generation, with a significant proportion of the global supply coming from Canadian producers. To determine the effect of the COVID-19 pandemic on the Canadian wood pellet industry, economic and market data were evaluated, in parallel with a survey of Canadian manufacturers on their experiences during the first three waves of the pandemic (March 2020 to September 2021). Overall, the impact of the pandemic on the Canadian wood pellet industry was relatively small, as prices, exports, and production remained stable. Survey respondents noted some negative impacts, mostly in the first months of the pandemic, but the quick recovery of lumber production helped to reduce the impact on wood pellet producers and ensured a stable feedstock supply. The pandemic did exacerbate certain pre-existing issues, such as access to transportation services and labour availability, which were still a concern for the industry at the end of the third wave in Canada. These results suggest that the Canadian wood pellet industry was resilient to disruptions caused by the pandemic and was able to manage the negative effects it faced. This is likely because of the integrated nature of the forest sector, the industry's reliance on long-term supply contracts, and feedstock flexibility, in addition to producers and end-users both being providers of essential services. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Reviews is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Government of Canada has embraced circular economy and is supporting an increasing number of initiatives in the field. However, implementation examples remain scattered and certain stakeholders are eager to see a greater level of commitment from policy makers. The purpose of this study is to provide a Canadian perspective on how, and to what extent, forest products are compatible with circular economy strategies. This topic was investigated through interviews with 16 Canadian experts in eco-design, circular economy, forest products and/or waste management, with a focus on construction and packaging. Efforts made by forest industries at the manufacturing stage to reduce resource consumption were acknowledged, but the implementation of other circular economy strategies, such as reuse, recycling and energy recovery, is uneven. While there is low-hanging fruit for incremental improvements, such as the processing of recovered lumber in wood panels and not mixing cardboard fibres with other paper streams to avoid downcycling, several barriers to the widespread adoption of the most promising strategies were identified. The experts consulted proposed several solutions to accelerate the deployment of circular economy strategies for forest products, for which government interventions would need to be tailored to the different policy readiness levels (PRLs) observed in the construction and packaging sectors. With circularity having economy-wide implications, setting a clear policy direction at the national level, with a circular economy roadmap for Canada for example, could accelerate coordinated implementation within and across sectors, including forest industries. [ABSTRACT FROM AUTHOR]

Burning forest biomass from renewable sources has been suggested as a viable strategy to help offset greenhouse gas (GHG) emissions in the energy generation sector. Energy facilities can, in principle, be retrofitted to produce a portion of their energy from biomass. However, supply uncertainties affect costs, and are an important impediment to widespread and sustained adoption of this strategy. In this paper, we describe a general approach to assess the cost of offsetting GHG emissions at co-generation facilities by replacing two common fossil fuels, coal and natural gas, with forest harvest residue biomass for heat and electricity production. We apply the approach to a Canadian case study that identifies the price of GHG offsets that could make the use of forest residue biomass feedstock attractive. Biomass supply costs were based on a geographical assessment of industrial harvest operations in Canadian forests, biomass extraction and transportation costs, and included representation of basic ecological sustainability and technical accessibility constraints. Sensitivity analyses suggest that biomass extraction costs have the largest impact on the costs of GHG emission offsets, followed by fossil fuel prices. In the context of other evaluations of mitigation strategies in the energy generation sector, such as afforestation or industrial carbon capture, this analysis suggests that the substitution of fossil fuels by forest residue biomass could be a viable and reasonably substantive short-term alternative under appropriate GHG emission pricing schemes. [ABSTRACT FROM AUTHOR]

As the largest carbon reservoir in ecosystems, soil accounts for more than twice as much carbon storage as that of vegetation biomass or the atmosphere. This paper examines spatial patterns of soil organic carbon (SOC) in Canadian forest areas at an eco-region scale of analysis. The goal is to explore the relationship of SOC levels with various climatological variables, including temperature and precipitation. The first Canadian forest soil database published in 1997 by the Canada Forest Service was analyzed along with other long-term eco-climatic data (1961 to 1991) including precipitation, air temperature, slope, aspect, elevation, and Normalized Difference Vegetation Index (NDVI) derived from remote sensing imagery. In addition, the existing eco-region framework established by Environment Canada was evaluated for mapping SOC distribution. Exploratory spatial data analysis techniques, including spatial autocorrelation analysis, were employed to examine how forest SOC is spatially distributed in Canada. Correlation analysis and spatial regression modelling were applied to determine the dominant ecological factors influencing SOC patterns at the eco-region level. At the national scale, a spatial error regression model was developed to account for spatial dependency and to estimate SOC patterns based on ecological and ecosystem factors. Based on the significant variables derived from the spatial error model, a predictive SOC map in Canadian forest areas was generated. Although overall SOC distribution is influenced by climatic and topographic variables, distribution patterns are shown to differ significantly between eco-regions. These findings help to validate the eco-region classification framework for SOC zonation mapping in Canada. [ABSTRACT FROM AUTHOR]

Over the last 25 years, greater understanding of natural dynamics in the boreal forest has led to the integration of forest ecosystem management principles into forest policy of several Canadian provinces and, in turn, to greater interest in developing silvicultural treatments that are grounded in natural stand-level dynamics – often referred to as natural disturbance-based silviculture. As a result, alternative silvicultural practices including variants of partial cutting are increasingly being applied in the boreal forest as an approach to balancing economic and ecological management objectives. While the numerous benefits of partial cutting reported in the literature are acknowledged, the objective of this paper is to provide an overview of factors or constraints that potentially limit the application of these practices in boreal Canada in the context of forest ecosystem management and natural disturbance-based silviculture. Among constraining factors, numerous studies have reported elevated mortality rates of residual stems following partial cutting, initial growth stagnation of residual trees, problems related to recruitment of desirable species and, on certain flat or lowland sites, risks of long-term decline in site and stand productivity. A number of operational challenges to partial cutting in the boreal forest are also presented and several avenues of research are proposed. [ABSTRACT FROM PUBLISHER]

The boreal zone and its ecosystems provide numerous provisioning, regulating, cultural, and supporting services. Because of its resources and its hydroelectric potential, Canada's boreal zone is important to the country's resource-based economy. The region presently occupied by Canada's boreal zone has experienced dramatic changes during the past 3 million years as the climate cooled and repeated glaciations affected both the biota and the landscape. For about the past 7000 years, climate, fire, insects, diseases, and their interactions have been the most important natural drivers of boreal ecosystem dynamics, including rejuvenation, biogeochemical cycling, maintenance of productivity, and landscape variability. Layered upon natural drivers are changes increasingly caused by people and development and those related to human-caused climate change. Effects of these agents vary spatially and temporally, and, as global population increases, the demands and impacts on ecosystems will likely increase. Understanding how humans directly affect terrestrial and aquatic ecosystems in Canada's boreal zone and how these effects and actions interact with natural disturbance agents is a prerequisite for informed and adaptive decisions about management of natural resources, while maintaining the economy and environment upon which humans depend. This paper reports on the genesis and present condition of the boreal zone and its ecosystems and sets the context for a detailed scientific investigation in subsequent papers published in this journal on several key aspects: carbon in boreal forests; climate change consequences, adaptation, and mitigation; nutrient and elemental cycling; protected areas; status, impacts, and risks of non-native species; factors affecting sustainable timber harvest levels; terrestrial and aquatic biodiversity; and water and wetland resources. [ABSTRACT FROM AUTHOR]

This paper provides an overview of the emerging role of Aboriginal people in Sustainable Forest Management (SFM) in Canada over the past decade. The 1996 Royal Commission on Aboriginal Peoples (RCAP) provided guidance and recommendations for improving Aboriginal peoples'' position in Canadian society, beginning with strengthening understanding and building relationships between Aboriginal and non-Aboriginal parties. This paper explores the extent to which advances in Aboriginal/non-Aboriginal relationships and Aboriginal forestry have been made as a result of RCAP's call for renewed relationships based on co-existence among nations. Such changes have begun to alter the context in which Aboriginal/non-Aboriginal relationships exist with respect to SFM. While governments themselves have generally not demonstrated the leadership called for by RCAP in taking up these challenges, industry and other partners are demonstrating some improvements. A degree of progress has been achieved in terms of lands and resources, particularly with co-management-type arrangements, but a fundamental re-structuring needed to reflect nation-to-nation relationships has not yet occurred. Other factors related to increasing Aboriginal participation in SFM, such as the recognition of Aboriginal and treaty rights, are also highlighted, along with suggestions for moving Aboriginal peoples'' SFM agenda forward in the coming years. [Copyright &y& Elsevier]

This paper examines the social capital that evolved in the Sustainable Forest Management Network (SFMN), one of the Canadian Networks of Centres of Excellence. Our longitudinal study shows a sevenfold increase in the total number of researchers and a high density of relationships among (researchers from) provinces across the country. The results of a social network analysis revealed that 52.6 percent of the network researchers maintained the same number of collaborators while 46.7 percent increased their number of collaborators enormously: the maximum increase in number of collaborators being 6900 percent and the minimum 6 percent. A bibliometric analysis suggested that the number of publications was strongly correlated to measures of social capital. From a science and innovation policy perspective, the finding that more than half of the researchers in the SFMN did not increase their personal networks of collaborators raises important questions. A theoretical model is proposed to examine whether funding agencies should focus on fostering various network structures and evolutions or rely on competition in the distribution of research funds through networks. The proposed model is designed to measure the impact of various network structures on the development of social capital and research output. [ABSTRACT FROM PUBLISHER]

Scaling up of observed point data to estimate regional carbon fluxes is an important issue in the context of the global terrestrial carbon cycle. In this study, the authors proposed a new model to scale up the eddy covariance data to estimate regional carbon fluxes using satellite-derived data. Gross primary productivity (GPP) and ecosystem respiration (RE) were empirically calculated using the normalized difference vegetation index (NDVI) and land surface temperature (LST) from the Moderate Resolution Imaging Spectroradiometer (MODIS). First, the model input is evaluated by comparing with the field data, then established and tested the model at the point scale, and then extended it into a regional scale. At the point scale, the empirical model could reproduce the seasonal and interannual variations in the carbon budget of the mature black spruce forests in Alaska and Canada sites, suggesting that seasonality of the NDVI and LST could explain the carbon fluxes and that the model is robust within mature black spruce forests in North America. Regional-scale analysis showed that the total GPP and RE between 2003 and 2006 were 1.76 ± 0.28 and 1.86 ± 0.26 kg CO2 m−2 yr−1, respectively, in mature black spruce forests in Alaska, indicating that these forests were almost carbon neutral. The authors' model analysis shows that the proposed method is effective in scaling up point observations to estimate the regional-scale carbon budget and that the mature black spruce forests increased in sink strength during spring warming and decreased in sink strength during summer and autumn warming. [ABSTRACT FROM AUTHOR]

"Snow gone" (SGN) stage is one of the critical variables that describe the start of the official forest fire season in the Canadian Province of Alberta. In this paper, our objective is to evaluate the potential of MODIS-based indices for determining the SGN stage. Those included: (i) enhanced vegetation index (EVI), (ii) normalized difference water index (NDWI) using the shortwave infrared (SWIR) spectral bands centered at 1.64 μm (NDWI1.64μm) and at 2.13 μm (NDWI2.13μm), and (iii) normalized difference snow index (NDSI). These were calculated using the 500 m 8-day gridded MODIS-based composites of surface reflectance data (i.e., MOD09A1 v.005) for the period 2006-08. We performed a qualitative evaluation of these indices over two forest fire prone natural subregions in Alberta (i.e., central mixedwood and lower boreal highlands). In the process, we generated and compared the natural subregion-specific lookout tower sites average: (i) temporal trends for each of the indices, and (ii) SGN stage using the ground-based observations available from Alberta Sustainable Resource Development. The EVI-values were found to have large uncertainty at the onset of the spring and unable to predict the SGN stages precisely. In terms of NDSI, it showed earlier prediction capabilities. On the contrary, both of the NDWI's showed distinct pattern (i.e., reached a minimum value before started to increase again during the spring) in relation to observed SGN stages. Thus further analysis was carried out to determine the best predictor by comparing the NDWI's predicted SGN stages with the ground-based observations at all of the individual lookout tower sites (approximately 120 in total) across the study area. It revealed that NDWI2.13μm demonstrated better prediction capabilities (i.e., on an average approximately 90% of the observations fell within ±2 periods or ±16 days of deviation) in comparison to NDWI1.64μm (i.e., on an average approximately 73% of the observations fell within ±2 periods or ±16 days of deviation). [ABSTRACT FROM AUTHOR]

The development of cooperation depends on the nature of deliberations among and between local stakeholders and the state as well as the context of deliberations, especially whether larger scale governance helps, hinders or overrides deliberative processes. However, the context of deliberations has not been a focus of past research on deliberation. The paper identifies the key context criteria that influenced deliberation and the development of cooperation in a comparative case study of two forest advisory committees in Ontario, Canada. The study uses cognitive mapping and network analysis techniques to identify key context criteria and concludes with five inferences regarding the influence of context on deliberation and cooperation that have implications for deliberation and decentralization theories. [ABSTRACT FROM AUTHOR]

Determining the feasibility of a large-scale afforestation program is one approach being investigated by the Government of Canada to increase Canada’s potential to sequester carbon from the atmosphere. Large-scale afforestation, however, requires knowledge of where it is suitable to establish and grow trees. Spatial models based on Boolean logic and/or statistical models within a geographic information system may be used for this purpose, but empirical environmental data are often lacking, and the association of these data to land suitability is most often a subjective process. As a solution to this problem, this paper presents a fuzzy-logic modeling approach to assess land suitability for afforestation of hybrid poplar ( Populus spp.) over the Prairie Provinces of Canada. Expert knowledge regarding the selection and magnitudes of environmental variables were integrated into fuzzy rule sets from which estimates of land suitability were generated and presented in map form. The environmental variables selected included growing season precipitation, climate moisture index, growing degree days, and Canada Land Inventory capability for agriculture and elevation. Approximately 150,000 km2, or 28% of the eligible land base within the Prairie Provinces was found to be suitable for afforestation. Accuracy assessments conducted with fuzzy accuracy methods provided a more descriptive assessment of the resulting land suitability map than figures generated from a more conventional Boolean-based accuracy measure. Modeling, mapping and accuracy assessment issues were identified for future extension of this work to map hybrid poplar land suitability over Canada. [ABSTRACT FROM AUTHOR]

This paper describes the emergence of a de-centered and privatized mode of governance in the Canadian forest sector. Using deliberative democratic theory as a descriptive foundation, it explores two key social facts that are arguably central to any historical analysis of this trend. First, increasing cultural pluralism challenges contemporary society to create new institutional arrangements that can incorporate a much larger, and often contested, array of public values into decision-making processes. Second, as management systems become more complex and science-driven, decision makers are finding it increasingly difficult to resolve issues of uncertainty and conflicting scientific evidence. De-centered forms of public participation provide important opportunities for government and industry to overcome these contemporary challenges, but certain side effects are also apparent. From the steering tactics of sponsoring agencies and corporations to the “ghettoizing” of environmental discourses, several implications are discussed. [ABSTRACT FROM AUTHOR]

Although succession may follow multiple pathways in a given environment, the causes of such variation are often elusive. This paper describes how changes in fire interval mediate successional trajectory in conifer-dominated boreal forests of northwestern Canada. Tree densities were measured 5 and 19 years after fire in permanent plots and related to pre-fire vegetation, site and fire characteristics. In stands that were greater than 75 years of age when they burned, recruitment density of conifers was significantly correlated with pre-fire species basal area, supporting the expectation of stand self-replacement as the most common successional pathway in these forests. In contrast, stands that were under 25 years of age at the time of burning had significantly reduced conifer recruitment, but showed no change in recruitment of trembling aspen ( Populus tremuloides). As a result, young-burned stands had a much higher probability of regenerating to deciduous dominance than mature-burned stands, despite the dominance of both groups by spruce ( Picea mariana and Picea glauca) and pine ( Pinus contorta) before the fire. Once initiated, deciduous-dominated stands may be maintained across subsequent fire cycles through mechanisms such as low on-site availability of conifer seed, competition with the aspen canopy, and rapid asexual regeneration of aspen after fire. We suggest that climate-related increases in fire frequency could trigger more frequent shifts from conifer to deciduous-dominated successional trajectories in the future, with consequent effects on multiple ecosystem processes. [ABSTRACT FROM AUTHOR]

Topographic correction based on sun-canopy-sensor (SCS) geometry is more appropriate than terrain-based corrections in forested areas since SCS preserves the geotropic nature of trees (vertical growth) regardless of terrain, view, and illumination angles. However, in some terrain orientations, SCS experiences an overcorrection problem similar to other simple photometric functions. To address this problem, we propose a new SCS+C correction that accounts for diffuse atmospheric irradiance based on the C-correction. A rigorous, comprehensive, and flexible method for independent validation based on canopy geometric optical reflectance models is also introduced as an improvement over previous validation approaches, and forms a secondary contribution of this paper. Results for a full range of slopes, aspects, and crown closures showed SCS+C provided improved corrections compared to the SCS and four other photometric approaches (cosine, C, Minnaert, statistical-empirical) for a Rocky Mountain forest setting in western Canada. It was concluded that SCS+C should be considered for topographic correction of remote sensing imagery in forested terrain. [ABSTRACT FROM AUTHOR]

Urban forests are socio-ecological systems where residents play a major role due to the number of trees located on residential property. A better understanding of residents' relationship with urban trees is needed to illuminate system dynamics and evaluate management strategies. Residents receive information about trees from a variety sources, including local news media, but the influence of local news media on residents' interactions with urban trees has not been considered. This article examines newspapers' framing of urban forests, focusing on if and how the framing changed as a result of a major storm that highlighted urban forest disservices. To do this, we analyzed articles from the Toronto Star, Mississauga News, and Brampton Guardian for a two-year period surrounding the 2013 ice storm. Our results indicate newspapers use a variety of ecosystem service and disservice themes in their urban forest coverage, but after the ice storm there was an increase in the number of themes represented in the average article and a shift to more frequent use of disservice themes. The results highlight the unique contribution of news media to urban forestry discourse, and the impact a weather event can have on the way urban forests are framed. La représentation des enjeux locaux de foresterie urbaine dans les journaux canadiens : les effets d'une forte tempête de verglas Les forêts urbaines sont des systèmes socioécologiques dans lesquels les résidents jouent un rôle majeur, étant donné le nombre d'arbres sur les terrains privés. Le rapport que les résidents entretiennent avec les arbres urbains doit être mieux compris afin d'éclairer la dynamique des systèmes et d'évaluer les stratégies de gestion. Les résidents disposent de nombreuses sources d'information au sujet des arbres, y compris les médias d'information locaux, mais l'influence de ces derniers sur les interactions des résidents avec les arbres urbains n'a pas encore été étudiée. L'objet de cet article porte sur le cadrage des forêts urbaines dans les journaux, en explorant tout particulièrement les changements de cadrage à la suite d'une forte tempête qui a fait ressortir les nuisances des forêts urbaines. Pour y parvenir, nous avons mené une analyse des textes publiés au cours d'une période de deux ans dans le Toronto Star, le Mississauga News et le Brampton Guardian au sujet de la tempête de verglas de 2013. D'après les résultats obtenus, ces journaux abordent divers sujets tant à propos des services écologiques que de leurs nuisances dans leur couverture de la forêt urbaine, mais après la tempête de verglas, on constate que les textes tendent à aborder davantage de sujets et mentionnent plus fréquemment les nuisances écologiques. Les résultats mettent en évidence l'apport particulier des médias d'information au discours sur la foresterie urbaine et les conséquences d'un événement météorologique sur le processus de cadrage des forêts urbaines. [ABSTRACT FROM AUTHOR]

The potential of forests and the forest sector to mitigate greenhouse gas (GHG) emissions is widely recognized, but challenging to quantify at a national scale. Forests and their carbon (C) sequestration potential are affected by management practices, where wood harvesting transfers C out of the forest into products, and subsequent regrowth allows further C sequestration. Here we determine the mitigation potential of the 2.3 x 106 km² of Canada's managed forests from 2015 to 2050 using the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3), a harvested wood products (HWP) model that estimates emissions based on product half-life decay times, and an account of emission substitution benefits from the use of wood products and bioenergy. We examine several mitigation scenarios with different assumptions about forest management activity levels relative to a base case scenario, including improved growth from silvicultural activities, increased harvest and residue management for bioenergy, and reduced harvest for conservation. We combine forest management options with two mitigation scenarios for harvested wood product use involving an increase in either long-lived products or bioenergy uses. Results demonstrate large differences among alternative scenarios, and we identify potential mitigation scenarios with increasing benefits to the atmosphere for many decades into the future, as well as scenarios with no net benefit over many decades. The greatest mitigation impact was achieved through a mix of strategies that varied across the country and had cumulative mitigation of 254 Tg CO2e in 2030, and 1180 Tg CO2e in 2050. There was a trade-off between short-term and long-term goals, in that maximizing short-term emissions reduction could reduce the forest sector's ability to contribute to longer-term objectives. We conclude that (i) national-scale forest sector mitigation options need to be assessed rigorously from a systems perspective to avoid the development of policies that deliver no net benefits to the atmosphere, (ii) a mix of strategies implemented across the country achieves the greatest mitigation impact, and (iii) because of the time delays in achieving carbon benefits for many forest-based mitigation activities, future contributions of the forest sector to climate mitigation can be maximized if implemented soon. [ABSTRACT FROM AUTHOR]

The Interior Wetbelt (IWB) of British Columbia includes the globally rare Inland Temperate Rainforest (ITR) that if managed for its substantial carbon (C) stocks can contribute to Canada's Nationally Determined Commitment under the Paris Climate Agreement. We provide spatially explicit estimates of above‐ and belowground live and dead biomass and soil C stocks derived from three sources: (1) government online Vegetation Resources Inventory (VRI); (2) the GlobBiomass spatial dataset; and (3) field plots (n = 27) within old‐growth forests of the ITR. For live aboveground C, we summarize C stocks by elevation classes and decadal forest age. The upper bound on total C densities (above‐ and belowground live and dead biomass and soil C) based on VRI was a maximum of 806 megagrams (Mg) C ha−1. The mean total biomass C density measured in field plots was 583 Mg C ha−1 with a maximum of 1275 Mg C ha−1, which is on par with some of the world's most C‐dense temperate forests. About half the C is in live biomass pools with the rest in dead biomass and soil organic C pools. The mean C density from the VRI over all elevations was 182 Mg C ha−1, with soil organic C ~40% and live tree stems ~27%. Vegetation Resources Inventory estimates were 75% lower than field‐based measurements with the greatest mismatch in areas with the highest C density. Approximately 22% of the IWB has been logged, the majority since 1970s, resulting in live above ground C declining by at least 18%, although this is likely an underestimate. Logging was heavily concentrated in low (<1000 m; 28.3% of elevation zone) to mid‐elevations (1000–2000 m; 20.9%) compared with upper elevations (>2000 m; 1.2%). The region contains underappreciated C stocks that can help Canada meet its climate and conservation targets, but only if there are major forestry reforms that protect C‐dense old‐growth forests, allow degraded forests time to recover the logging‐related C debt, and improve monitoring of C stocks and stock changes. [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]

Background Forest based climate mitigation emerged as a key component of the Paris Agreement, and thus requires robust science to reduce uncertainties related to such strategies. The aim of this study was to assess and compare the cumulative effects on carbon dynamics of forest management and climate change on boreal and northern temperate forest sector in eastern Canada for the 2020–2100 period. Methods We used the spatially explicit forest landscape model LANDIS-II and its extension Forest Carbon Succession, in conjunction with the Carbon Budget Model for Harvested Wood Products framework. We simulated the dynamics of forest composition and carbon flows from forest ecosystems to wood products and their substitution effect on markets under increasing climate forcing, according to a tonne-year approach. Simulations were conducted for a series of forest management scenarios based on realistic practices principally by clearcut in the boreal territory and continuous-cover forestry in the northern temperate one. These scenarios included: i) a business-as-usual scenario (BaU), representing the current management strategy, ii) increased harvesting by 6.3% to 13.9%, iii) increased conservation (i.e. reduced harvesting by 11.1% to 49.8%), iiii) and a scenario representing the natural evolution of the forest landscape (i.e. without any management activity). Results Our study revealed that increasing harvesting levels had contrasting effects on the mitigation potential in northern temperate (enhance net sequestration) and boreal forest sector (enhance net emissions) in comparison to the BaU from 2040 onwards, regardless of the future climate. Carbon storage in wood products and the substitution effect were not sufficient to offset carbon emissions from ecosystems. Moreover, climate change had a strong impact on the capacity of both landscapes to act as carbon sinks. Northern temperate landscapes became a net source of carbon over time due to their greater vulnerability to climate change than boreal landscapes. Conclusions Our study highlights the need to consider the initial landscape characteristics in simulations to maximize the mitigation potential of alternative forest management strategies. The optimal management solution can be very different according to the characteristics of forest ecosystems. This opens the possibility of optimizing management for specific forest stands, with the objective of maximizing the mitigation potential of a given landscape. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Public Policy is the property of University of Toronto Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Over the last thirty years, Aboriginal peoples, forestry companies and governments in Canada have developed a wide variety of arrangements and mechanisms aimed at fostering collaboration and establishing an increasing Aboriginal role in managing and harvesting forestlands. This paper seeks to facilitate the analysis and investigation of various forms of collaboration by presenting a typology based upon institutional arrangements and desired outcomes. Development of the typology followed an iterative process of categorisation, description, testing and revision, using scientific and grey literature combined with testing against an ever-widening number of communities; firstly in Quebec, then in six provinces and finally with 474 communities across the country. We identify five principal forms of collaborative arrangement, each with a number of sub-types: treaties and other formal agreements that establish roles and responsibilities; planning and management activities; influence on decision-making; forest tenures; and economic roles. The application and utility of this typology is illustrated through the examples of four communities, each of which is engaged in several different collaborative arrangements. The typology demonstrates the variety of arrangements that are available to encourage Aboriginal involvement in Canada's forest sector while also provided a basis for future work in comparing the benefits of different arrangements or in analysing the effectiveness of policies. [Copyright &y& Elsevier]

Copyright of Canadian Political Science Review is the property of Canadian Political Science Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Political Science Review is the property of Canadian Political Science Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The well-being of people living in forest-dependent communities has been studied extensively, but little research has explored how this relationship has changed over time. Some theories suggest that regional differences in well-being should decrease, through the flow of capital and labour, while other work suggests that these inequalities will grow. Our research uses Census of Canada data at the census subdivision level at 5-year intervals between 1986 and 2001 to describe regional differentiation in the relationship between employment in forest sectors (logging, services, pulp and lumber) and unemployment and median family income as indicators of well-being. We found general declines, which varied somewhat by region, over time in forest dependence across the regions and changing composition of the forest industry across these sectors. The relationship between forest dependence and well-being over time varied by region, largely tied to intra-industry sector shifts. [ABSTRACT FROM AUTHOR]

An important element of resource management and conservation is an understanding of the tradeoffs between marketed products, such as timber, and measures of environmental quality, such as biodiversity. In this paper, we develop an integrated economic-ecological spatial optimization model that we then apply to evaluate alternate forest policies on a 560,000km2 study region of managed boreal forest in Alberta and British Columbia, Canada. The integrated model incorporates dynamic forest sector harvesting, current levels of oil and gas sector development, coarse-filter or habitat-based old forest indicators, a set of empirical forest bird abundance models, and statistical models of the natural and current fire regimes. Using our integrated model, economic tradeoff curves, or production possibility frontiers, are developed to illustrate the cost of achieving coarse-filter targets by a set time (50 years) within a 100-year time horizon. We found levels of ecological indicators and economic returns from the timber industry could both be increased if spatial constraints imposed by the current policy environment were relaxed; other factors being equal, this implies current policy should be revised. We explore the production possibility frontier's relationship to the range of natural variation of old forest habitat, and show how this range can be used to guide choices of preferred locations along the frontier. We also show that coarse-filter constraints on the abundance of certain habitat elements are sufficient to satisfy some fine-filter objectives, expressed as the predicted abundances of various species of songbirds. [Copyright &y& Elsevier]

Abstract: Accuracy in population estimation from individual measurement has been traditionally a research focus in both theoretical and applied ecology. In forest sciences, estimation of productivity and value recovery of forest products is essential for decision-making to achieve the goal of sustainable forest management. In this paper, we review the basic structure of data in forest sciences, describe commonly used statistical procedures in obtaining population estimates, and examine the accuracy associated with the forest products value estimation using forest inventory data of Manitoba, Canada. Our results suggested that simplified statistical procedures could bring about a wide range of bias in estimating lumber value recovery at the stand level, and improved understanding of stand structure and its reconstruction through computer simulation could be essential in reducing the bias involved in the estimation. [Copyright &y& Elsevier]

The scientific community, forest managers, environmental organizations, carbon-offset trading systems and policy-makers require tools to account for forest carbon stocks and carbon stock changes. In this paper we describe updates to the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) implemented over the past years. This model of carbon-dynamics implements a Tier 3 approach of the Intergovernmental Panel on Climate Change (IPCC) Good Practice Guidance for reporting on carbon stocks and carbon stock changes resulting from Land Use, Land-use Change and Forestry (LULUCF). The CBM-CFS3 is a generic modelling framework that can be applied at the stand, landscape and national levels. The model provides a spatially referenced, hierarchical system for integrating datasets originating from different forest inventory and monitoring programs and includes a structure that allows for tracking of land areas by different land-use and land-use change classes. Ecosystem pools in CBM-CFS3 can be easily mapped to IPCC-defined pools and validated against field measurements. The model uses sophisticated algorithms for converting volume to biomass and explicitly simulates individual annual disturbance events (natural and anthropogenic). Several important scientific updates have been made to improve the representation of ecosystem structure and processes from previous versions of CBM-CFS. These include: (1) an expanded representation of dead organic matter and soil carbon, particularly standing dead trees, and a new algorithm for initializing these pools prior to simulation, (2) a change in the input data requirement for simulating growth from biomass to readily available merchantable volume curves, and new algorithms for converting volume to biomass, (3) improved prediction of belowground biomass, and (4) improved parameters for soil organic matter decay, fire, insect disturbances, and forest management. In addition, an operational-scale version of CBM-CFS3 is freely... [Copyright &y& Elsevier]

Abstract: This paper will discuss TRIPLEX-Flux, a process-based model that estimates net ecosystem production (NEP) as well as analyzing the level of sensitivity of the model''s response by simulating CO2 flux in an existing old black spruce BOREAS site in central Canada. The research objectives were: (1) to test the TRIPLEX-Flux model simulations against flux tower measurements; and (2) to examine parameter and input variable effects on model response via sensitivity analysis. Validation of NEP data at 30min intervals derived from tower and chamber measurements showed that the NEP data from the model corresponded well with the measured NEP from the BOREAS site (R 2 >0.65). Sensitivity analysis demonstrated different levels of sensitivity between morning and noon periods and from the current to doubled atmospheric CO2 concentrations. Additionally, the comparison of different algorithms to calculate stomatal conductance showed that the NEP predicted by the model using the iteration algorithm was consistent with the results using a constant C i/C a of 0.74 for current and 0.81 for doubled CO2 concentrations. Varying parameter and input variable values by ±10% resulted in a similar model response between morning and noon periods (less than or equal to 27.6% and 27.4%, respectively). Most parameters were more sensitive at noon than they were in the morning except for those that were correlated with air temperature, suggesting that air temperature has considerable influence over model sensitivity for these parameters/variables. Air temperature effect was greater under doubled than it was under current atmospheric CO2 concentrations. In contrast, model sensitivity to CO2 decreased under doubled CO2 concentrations. [Copyright &y& Elsevier]

This paper explores the potential for collaborative governance approaches to support Cumulative Effects Assessment (CEA) in the Cree territory of Eeyou Istchee, located in Northern Quebec, Canada, where a long history of large-scale hydroelectricity development, mining and forestry activities have negatively affected wildlife populations, imposing burdens on the traditional food systems and livelihoods of local Indigenous communities. Drawing on key informant interviews with policy actors from government, non-government and private sector organizations working on Impact Assessment in Eeyou Istchee, the potential for more decentralized and networked approaches to regional wildlife monitoring and baseline data collection in support of CEA is considered. Results suggest a shared willingness to collaborate towards improving the overall regional environmental conditions and to generate long-term data on wildlife population and distribution. Challenges include the absence of essential supporting programs (land-use plans, regional environmental frameworks, lead monitoring agencies, designated funding), and high levels of distrust between proponents and NGOs which combine to suppress the initiation of collaborative governance processes as well as the potential utility of any regional monitoring program that might be established. The need for leadership to facilitate reciprocal knowledge flows among actors, build trust and enable long-term cooperative structures based on a shared vision and goal congruency is identified. • Traditional wild food species are core to sustainable development in Eeyou Istchee. • Cumulative effects (CE) of development are negatively impacting traditional foods. • Could collaborative governance approaches enhance regional wildlife monitoring? • A foundation for the collaborative governance of wildlife monitoring is identified. • Policy experimentation with collaborative approaches to monitoring is warranted. [ABSTRACT FROM AUTHOR]

In the Canadian Western Boreal Plain (WBP), wetlands (ponds and peatlands) comprise up to 50% of the landscape and represent unique habitat where summer precipitation is often outpaced by evapotranspiration and hillslope groundwater position does not follow topography. In this sub-humid location, groundwater fluxes and stores in riparian peatlands influence pond water levels and root zone moisture sources for forested uplands. To accurately describe the transport and retention of water in peat, it is important to consider peat subsidence. This paper quantifies the amount and effect of seasonal subsidence in a riparian peatland in the Utikuma Lake region in north-central Alberta, Canada. Results demonstrate that the deep and poorly decomposed peat deposits are resistant to compression, and that thick (and persistent) ground frost hinders pore collapse (shrinkage) above the water table until late summer when the ground has thawed. Even then, subsidence is still limited to the top 50 cm and is not closely related to changes in peatland water table or pond water level. Thus the water balance of these ponds and riparian areas appears to be less sensitive to peat volume changes than it is to the persistence of a substantial frost layer well into the snow-free period. [ABSTRACT FROM AUTHOR]

In forestry, the availability of high spatial resolution (<1 m/pixel) imagery from new earth observation satellites like Ikonos favours a shift in the image analysis paradigm from a pixel-based approach towards one dealing directly with the essential structuring element of such images: the individual tree crown (ITC). This paper gives an initial assessment of the effects of 1 m and 4 m/pixel spatial resolutions (panchromatic and multispectral bands, respectively) on the detection, delineation, and classification of the individual tree crowns seen in Ikonos images. Winter and summer Ikonos images of the Hudson plantation of the Petawawa Research Forest, Ontario, Canada were analyzed. The panchromatic images were resampled to 0.5 m/pixel and then smoothed using a 3 × 3 kernel mean filter. A valley-following algorithm and rule-based isolation module were applied to delineate the individual tree crowns. Local maxima within a moving 3 × 3 window (i.e., Tree Tops) were also extracted from the smoothed images for comparison. Crown delineation and detection results were summarised and compared with field tree counts. Overall, the ITC delineation and the local maxima approaches led to tree counts that were on average 15 percent off for both seasons. Visual inspection reveals delineation of clusters of two or three crowns as a common source of error. Crown-based species spectral signatures were generated for six classes representing conifer species, plus a hardwood class and a shrub class. After the ITC-based classification, classification accuracy was ascertained using separate test areas of known species. The overall accuracy was 59 percent. Important confusion exists between red and white spruces, and mature versus immature white pines, but post-classification regroupings into single spruce and white pine classes led to an overall accuracy of 67 percent. [ABSTRACT FROM AUTHOR]

The James Bay Agreement reinforces the rights of the Crees to 500,000 km² of territory in the boreal forest and taiga of northern Quebec. In it, consultation and environmental assessment (EA) mechanisms were set up to ensure the Crees' direct involvement in environmental decisions. This paper addresses three matters: the influence of Native involvement in the EA process; updating the EA process under the Agreement to in-corporate the apparently new tools of strategic environmental assessments (SEAs); and adaptation of the concept of SEA to the Native context. Our analysis focuses on the experience gained from large hydroelectric development projects, recent and planned mining developments, and forestry operations. [ABSTRACT FROM AUTHOR]

The Canadian forest sector provides a rich contextual basis for examining organizational legitimacy and legitimating mechanisms. The author used qualitative methods and discourse analysis to explore how the Canadian forest sector exhibits a hybrid mix of substantive and symbolic management of legitimacy and of procedural and symbolic processes of legitimation. Findings support the mystifying nature of "green" legitimation and the superficial and mystifying nature of some of the discourse that is being used in this sector. In some cases, language is being used to attempt to change definitions of social legitimacy to enhance a record of sustainable forest management practice. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Public Policy is the property of University of Toronto Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)