bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coping with complexity: Designing low-impact forest bioenergy systems using an adaptive forest management framework and other sustainable forest management tools
Authors: Lattimore Brenna , Smith Tat , Richardson Jim 
Published: February 2014

Forest fuel production is a growing industry in Canada and elsewhere, as governments strive to increase energy security and find alternatives to the use of fossil fuels. While forest bioenergy can provide environmental benefits such as renewability and carbon emissions reductions, the industry can also pose environmental risks through increasing pressure on forest resources. Because large-scale forest bioenergy production is relatively new to Canada, much is still unknown about how such an industry might evolve and impact forest ecosystems. These unknowns, along with the cross-sectoral, multistakeholder nature of the industry, make planning for sustainable forest bioenergy systems quite challenging. In this paper, we introduce some of the challenges to creating sustainable systems, and we discuss how sustainable forest management frameworks like Adaptive Forest Management and Sustainable Forest Management Certification can help to meet these challenges. We also discuss the importance of technology transfer to ensuring that the best available knowledge forms the basis for effective standards and management plans. Sustainable forest management frameworks can help to organize, distil and communicate the growing body of research on forest bioenergy production, link policy to practice through the creation of standards, and incorporate provisions for continual learning and system adaptation, all of which are key to the long-term sustainability of the rapidly evolving forest bioenergy sector. Key words: bioenergy, sustainable forest management frameworks, adaptive forest management, certification, standards, technology transfer
The TRANSFOR success story: International forestry education through exchange
Authors: Spence John R. , MacLean David A. , Spiecker Heinrich , Drummond Alex , Jaeger Dirk , Stadler Marianne , Cahalan Christine , Karlsson Anders , Kenny Andy , Larson Bruce , Mola-Yudego Blas , Sterner Maria , Wästerlund Diane , Valinger Erik 
Published: February 2014

The TRANSFOR (Transatlantic Education for Global Sustainable Forest Sector Development) program has promoted international student and staff exchanges among four Canadian (Alberta, British Columbia, New Brunswick and Toronto) universities and universities in four European countries (Germany [Freiburg], Finland [Joensuu], Sweden [Swedish University of Agricultural Sciences, Umeå] and the United Kingdom [Bangor University, Wales]). The program incorporated five components: one or two semester study visits for undergraduate forestry students, working internships, summer field courses, study visits for academic staff, and TRANSFOR project meetings. The summer field courses were a highly innovative part of the program and allowed students to spend three to four weeks learning about forestry activities and challenges on a continent different from that of their home institution. The program fostered internationally focused understanding of forest ecology and management, as well as economic and cultural factors, as will be required to develop effective international standards for sustainable forest management. Most student participants reported that it was a very positive experience and a high point of their education. Key words: international exchange, undergraduate forestry students, internships, field courses, international forestry
Predicting the effects of woodcutting and moose browsing on forest development in Gros Morne National Park, Newfoundland, Canada
Authors: Zhu Xinbiao , Bourque Charles P.-A. , Taylor Scott , Cox Roger , Wentzell Carson 
Published: February 2014

Long-term scenario analysis was used to predict the effects of domestic harvesting and moose (Alces alces) browsing on forest growing stock, species composition, and age-class distribution for two groups of managed forest blocks dominated by balsam fir (Abies balsamea [L.] Mill.) in Gros Morne National Park (GMNP), western Newfoundland. Four scenarios were examined. The first scenario assumed no timber harvesting and light moose browsing. Transition rules applied to this scenario came from neighbouring industrial forests, where moose populations are regulated by hunting. The other test scenarios use GMNP-specific transition rules to address increased moose browsing in the park, where hunting has been prohibitedsince the park’s inception in 1973. One of the three tested scenarios was also given a “no timber harvest treatment” so that the effects of moose browsing on park forests may be quantified by comparison with the first scenario. The two remaining test scenarios were designed to address compound effects of timber harvesting and moose browsing within the park, each representingan alternative management sce- nario currently being implemented in GMNP. For both harvest scenarios, the overall achievable wood volume was found to be at least five orders of magnitude lower than growing stock, thus providing sufficient volume for the ongoing domestic wood- cutting program (1973-2060) in the park. The proposed levels of woodcutting were predicted to have little impact on forest growing stock and old-growth forest after 160 years of management, but not on maintaining white birch (Betula papyrifera Marsh.), which is already in low numbers. In contrast, moose browsing, although it was predicted to have little effect on age-class distribution, was estimated to cause a 12% to 32% reduction in growing stock over a 160-year planning horizon, depending on the scenario. This was characterized by a 47% to 50% reduction in growing stock of balsam fir and a 50% to 87% reduction in white birch, and a commensurate expansion in low-density black spruce (Picea mariana [Mill.] BSP) and grassland cover. Key words: balsam fir, black spruce, domestic harvest, grassland, scenario analysis, white birch
Effects of fire severity on early survival and growth of planted jack pine, black spruce and white spruce
Authors: Wang G. Geoff , Kemball Kevin J 
Published: February 2014

Two boreal mixedwood stands burned by the 1999 Black River wildfire in southeastern Manitoba, Canada were selected to study the effect of fire severity on early survival and growth of planted jack pine (Pinus banksiana), black spruce (Picea mariana) and white spruce (Picea glauca) seedlings. In each stand, three fire severity classes (scorched, lightly burned, and severely burned) were identified based on the degree of forest floor consumption. Fire severity was not a significant factor on mortality. No mortality difference was found among species, except for year 5 when jack pine had significantly higher mortality than both black spruce and white spruce. Jack pine and black spruce had their highest mortality in year 4, while white spruce had its highest mortality in year 1. Under natural competition, seedling growth increased with increasing fire severity. When competition was removed, fire severity did not affect seedling growth. Regardless of fire severity and competition, jack pine had better diameter and height growth than black spruce, which, in turn, grew slightly taller than white spruce. Planted seedlings faced less intense vegetation competition on severely burned plots compared to scorched or lightly burned plots. Regardless of fire severity and species, competition increased with time since planting. Our study results indicate that planting immediately after a wildfire is a viable option to establish conifer components on burned boreal mixedwood stands. Key words: fire severity, plantation, regeneration, Pinus banksiana, Picea mariana, Picea glauca
Old-growth forest values: A narrative study of six Canadian forest leaders
Authors: Moyer Joanne M , Duinker Peter N , Cohen Fay G 
Published: February 2014

Old-growth forest is the subject of widespread conflict. Understanding associated values and attitudes in society is necessary for its sustainable management. We investigated old-growth values through a narrative study employing in-depth interviews with six leaders in Canada’s forest sector. Old-growth forest was valued for its natural ecological systems, biotic components, and experiential aspects. The study highlights the importance of value discourse within the forest sector.Key words: old-growth forest, values, Canada, forest management
A word of caution when planning forest management using projections of tree species range shifts
Authors: Lo Yueh-Hsin , Blanco Juan A. , Kimmins J. P. (Hamish) 
Published: February 2014

In this note we raise our concerns about the use of climate envelope models as a basis for forest planning under climate change. Such models assume constant relationships among tree species presence, abundance or growth rates and climatic variables, and that these can be transferred from their current distribution areas to areas that are predicted to have a similar future climate. Climate is an important determinant of tree species distributions, but its effects are mediated through soils, competition from other plant species, herbivores, diseases, insects and fire. This complexity should be addressed when making predictions about plant species distribution changes. If forecasts based only on climate are accepted uncritically and become the basis for forest policy and practice, there could be important consequences for the success of forest management. We illustrate the issue with the historical response of tree growth to climate variability for three conifer species along an altitudinal gradient in southern interior British Columbia. The growth–climate relationships differ not only among species but also between ecological zones, which implies that the different combinations of tree species and site will react differently to the same change in climate. All things considered, caution is needed when developing management plans using predicted future tree distributions based only on current/past tree/climate relationships. Key words: climate-envelope models, climate change, species distributions, dendroclimatology
Natural regeneration of jack pine on clay soils following harvesting and site preparation: Seventh-year results
Authors: Béland Martin , Calmels Sébastien , Bergeron Yves 
Published: February 2014

This study examines the operational feasibility of six treatments to regenerate jack pine (Pinus banksiana Lamb.) naturally without fire following harvesting on clay soils in the southeastern boreal forest of Quebec. The experiment is a randomized complete block design. Techniques used were a final cutting in 1993 with manual on-site delimbing or roadside delimbing combined with three methods of soil scarification (WadellTM, La TaupeTM and a control) performed in the Spring of 1994 compared to an adjacent jack pine plantation established in 1994 after Wadell scarification. Seven growing seasons later, the present article compares stand composition, competing vegetation, regeneration and growth of jack pine between the different treatments as well as an adjacent plantation. Natural regeneration produced mixed stands with an adequate 52% average jack pine stocking. Roadside and on-site delimbing produced similar jack pine stocking on average. However, the plantation showed 83% stocking and better performance than natural regeneration in terms of height (2.48 m vs. 1.7 m for natural regeneration), diameter (41 mm vs. 22 mm for natural regeneration) and jack pine dominance. Therefore, if natural regeneration is desired, roadside delimbing is to be recommended since it provides sufficient seed and does avoid early jack pine growth reductions caused by slash. On clay soils, scarification seems to have been optional. Nevertheless, it slightly increased seedling growth and in this way, the treatment combining road-side delimbing and an extensive scarification can be an effective jack pine natural regeneration treatment.Key words: Pinus banksiana Lamb., natural regeneration, stocking coefficient, delimbing, scarification, boreal mixed wood, seedlings
An ecological land classification approach to modeling the production of forest biomass
Authors: Pokharel Bharat , Dech Jeffery P 
Published: February 2014

Forest site classification is a prerequisite to successful integrated forest resources planning and management. Traditionally,site classification has emphasized a phytocentric approach, with tools such as the site index having a rich and longhistory in forest site evaluation. The concept of site index was primarily devised to assess site productivity of an even-aged,single-species stand. Site index has been the primary method of forest site evaluation in support of management for traditionalforest products. However, this method of site classification has been criticized as the needs, perspectives andsocial values of the public regarding forest management have changed the emphasis from timber production to multiplevalueforestry practices. There are alternative approaches to forest site classification that have the potential to meet thegrowing demands placed on forest information for inventory and modeling purposes. Ecological Land Classification(ELC), is a phytogeocentric approach that stratifies the landscape into ecologically meaningful units (ecosites) based onsubstrate characteristics, moisture regime and canopy composition. This approach offers a more holistic view of site productivityevaluation; however, until recently it has been difficult to acquire data to support widespread mapping ofecosites. Remote sensing technology along with predictive modeling and interpretive mapping techniques make the applicationof an ecosite-based approach at the forest landscape level possible. As forest management moves towards the considerationof a broader set of resources (e.g., woody biomass), there is an opportunity to develop new tools for linking forestproductivity to the sustainable production of forest bioproducts with forest ecosites as a solid foundation forsegmenting the landscape. Key words: forest site classification, site index, site productivity, Ecological Land Classification (ELC), ecosites, forest biomass,bioproducts
Biomass availability in eastern Ontario for bioenergy and wood pellet initiatives
Authors: Levin Rachele , Krigstin Sally , Wetzel Suzanne 
Published: February 2014

Interest in wood-based bioenergy and pelletization is growing in Ontario, and the province is taking steps to encouragethese new technologies. A survey of eastern Ontario sawmills was conducted to assess residue production and availabilityfor bioenergy and pellet applications. Approximately 259 000 oven dry tonnes of sawmill residues are produced annuallyin eastern Ontario, but most of this fibre is absorbed by existing markets and would not be available for bioenergy orpellet initiatives. However, another source of wood fibre exists that is both abundant and unutilized: traditional pulpwood.While establishment costs of bioenergy and pellet facilities are high, pulpwood is locally available in large quantities.Given the right incentives, bioenergy and pelletization could provide alternative energy sources and support the forestindustry and rural economy. Key words: sawmill residue, wood biomass, bioenergy, pellets, eastern Ontario
Energy from forest biomass in Ontario: Getting beyond the promise
Authors: Mabee W E , Mirck J. , Chandra R. 
Published: February 2014

The recent decline in Ontario’s forest sector has resulted in the idling or closure of many mills, creating an opportunityfor forest-derived bioenergy supported by the Ontario Green Energy and Green Economy Act. Combined heat and powerproduction from forest biomass seems to provide an optimal balance between energy supplied and employment opportunities.This option could provide Ontario with 5.3% of electricity and 1.5% of heat energy needs. The province couldsustainably support up to 12 60-MW installations. Five key recommendations are advanced, including the need for abioenergy strategy within the province, options for developing funding for this sector, and the possibility of creating abioenergy network using existing research assets within Ontario. Key words: forest sector, Green Energy and Green Economy Act, combined heat and power, black liquor gasification,wood pellets, liquid biofuels for transport, ethanol, Fischer-Tropsch diesel, forest biomass supply
Partial harvests in the boreal forest: response of the understory vegetation five years after harvest
Authors: Bescond Hervé , Fenton Nicole J , Bergeron Yves 
Published: February 2014

In the eastern boreal forest of Canada long fire cycles allow for a significant portion of stands to become old growth. Theseold-growth boreal forest stands are subjected to secondary disturbances that create uneven structure, which supports avariety of types of organisms. In order to maintain the proportion of stands with uneven structure on the landscape, partialcuts have been suggested as a management technique that could create or maintain these uneven structures. This studycompares the effects of partial and low-retention harvests and un-harvested control on understory plants in four sites fiveyears after harvest. The relative abundance of species was examined by a habitat group. While richness did not vary amongtreatments, increasing severity of harvest favoured pioneer species that prefer disturbed mineral soil and high light levels.Sites with thicker organic layers that were harvested in the winter were significantly less impacted by both partial and lowretentionharvest. Canopy opening alone had little impact in the three most northern sites. As old-growth black spruceforests are open by nature, this suggests that soil perturbation is a bigger driver of community change after harvest thanproportion of canopy removed for this forest type. Key words: Quebec, Picea mariana, harvest, variable retention, sustainable forest management, understory, structuralretention, vegetation
Abiotic and biotic factors used to assess decline risk in red pine (Pinus resinosa Ait.) plantations
Authors: McLaughlin J A , Hsiang T , Hayden G Halicki , Greifenhagen S 
Published: February 2014

This study was conducted to assess causes of unprecedented rates of mortality in maturing, commercial-sized red pine(Pinus resinosa Ait.) plantations in southern Ontario, Canada. Concentrated and diffuse mortality as well as windthrowof living trees were observed in many plantations, while others seemed disease-free. Nine sites exhibiting recent mortality(diseased) plus three not exhibiting disease (healthy) were selected. In sample plots at each site, abiotic site factors, hostcharacteristics, and insect pests and fungal pathogens were assessed. Tree mortality was attributed to Armillaria root disease,annosus root rot, black pineleaf scale, drought, and iron deficiency. The single abiotic factor that distinguishedhealthy sites from diseased sites was C soil horizon pH, which averaged 8.35 on diseased sites compared to 6.55 on healthysites. Rooting was also deeper on healthy sites than on diseased sites. We suggest that an alkaline C horizon may result inshallower rooting and greater susceptibility to drought stress, rendering trees less resistant to root disease pathogens andinsect pests. The pH of the C horizon and the depth of the A and B horizons may be useful as indicators of the likelihoodof red pine mortality and to guide the choice of management objectives for plantations. Key words: red pine mortality, root disease, calcareous soil, rooting depth, Armillaria
Evaluation of an Efficient Approach for Target Tracking from Acoustic Imagery for the Perception System of an Autonomous Underwater Vehicle
Authors: Villar Sebastián A. , Acosta Gerardo G. , Sousa André L. , Rozenfeld Alejandro 
Published: February 2014

This article describes the core algorithms of the perception system to be included within an autonomous underwater vehicle (AUV). This perception system is based on the acoustic data acquired from side scan sonar (SSS). These data should be processed in an efficient time, so that the perception system is able to detect and recognize a predefined target. This detection and recognition outcome is therefore an important piece of knowledge for the AUVs dynamic mission planner (DMP). Effectively, the DMP should propose different trajectories, navigation depths and other parameters that will change the robot's behaviour according to the perception system output. Hence, the time in which to make a decision is critical in order to assure safe robot operation and to acquire good quality data; consequently, the efficiency of the on-line image processing from acoustic data is a key issue. Current techniques for acoustic data processing are time and computationally intensive. Hence, it was decided to process data coming from a SSS using a technique that is used for radars, due to its efficiency and its amenability to on-line processing. The engineering problem to solve in this case was underwater pipeline tracking for routine inspections in the off-shore industry. Then, an automatic oil pipeline detection system was developed borrowing techniques from the processing of radar measurements. The radar technique is known as Cell Average – Constant False Alarm Rate (CA – CFAR). With a slight variation of the algorithms underlying this radar technique, which consisted of the previous accumulation of partial sums, a great improvement in computing time and effort was achieved. Finally, a comparison with previous approaches over images acquired with a SSS from a vessel in the Salvador de Bahia bay in Brazil showed the feasibility of using this on-board technique for AUV perception.
Parametric surface and properties defined on parallelogrammic domain
Authors: Fan Shuqian , Zou Jinsong , Shi Mingquan 
Published: February 2014

Abstract
Similar to the essential components of many mechanical systems, the geometrical properties of the teeth of spiral bevel gears greatly influence the kinematic and dynamic behaviors of mechanical systems. Logarithmic spiral bevel gears show a unique advantage in transmission due to their constant spiral angle property. However, a mathematical model suitable for accurate digital modeling, differential geometrical characteristics, and related contact analysis methods for tooth surfaces have not been deeply investigated, since such gears are not convenient in traditional cutting manufacturing in the gear industry. Accurate mathematical modeling of the tooth surface geometry for logarithmic spiral bevel gears is developed in this study, based on the basic gearing kinematics and spherical involute geometry along with the tangent planes geometry; actually, the tooth surface is a parametric surface defined on a parallelogrammic domain. Equivalence proof of the tooth surface geometry is then given in order to greatly simplify the mathematical model. As major factors affecting the lubrication, surface fatigue, contact stress, wear, and manufacturability of gear teeth, the differential geometrical characteristics of the tooth surface are summarized using classical fundamental forms. By using the geometrical properties mentioned, manufactura-bility (and its limitation in logarithmic spiral bevel gears) is analyzed using precision forging and multi-axis freeform milling, rather than classical cradle-type machine tool based milling or hobbing. Geometry and manufacturability analysis results show that logarithmic spiral gears have many application advantages, but many urgent issues such as contact tooth analysis for precision plastic forming and multi-axis freeform milling also need to be solved in a further study.