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With its northern location, the exposure and vulnerability of Canada's forest ecosystems to climate change impacts are all too glaring. While there is now an extensive body of literature describing expected climate change impacts and potential responses, studies characterizing the implementation of adaptation and mitigation practices in forest management remain rare in the Canadian forest sector. Using a systematic literature review, we examined reports on forest management practices implemented in response to climate change, specifically focusing on governance and institutional arrangements that either support or limit climate change adaptation and mitigation responses. Our literature sample size of 24 documents suggests that the body of literature reporting on adaptation and mitigation practices in forest management is scarce. Governments remain the dominant actors providing funding and leading the implementation and reporting of climate change adaptation practices, primarily in response to national or international climate change commitments. Forest practices such as enhanced silviculture, assisted migration, and nature-based solutions were the most frequently reported. However, given the scarcity of literature, it is difficult to conclude the scope of climate change adaptation practice uptake in Canada. Barriers such as lack of information/data, inter-jurisdictional knowledge transfer, policy conflicts, forest tenure models, technical capacity gaps, and economic barriers to adaptation need to be overcome to strengthen climate change response in forest management. Better coordination of reporting at the provincial and national levels and improved information flows between private sector organizations and governments are needed. [ABSTRACT FROM AUTHOR]

Canada is recognized as a global leader in sustainable forest management. Canadian forests and the forest sector remain vital pillars of the Canadian economy and home to many rural and remote communities. However, climate change is an existential threat to the sustainability of forests and forest-dependent communities. While both direct and indirect threats posed by climate change to Canada's forest sector are now well understood, our understanding of specific forest practices that have emerged from the body of science to mitigate and adapt to climate change impacts is not well documented. Through a review of the scientific and grey literature, this study expands our knowledge and operational gaps associated with implementing climate change adaptation and mitigation practices in Canadian forests. The study found a dearth of literature specifically dedicated to reporting on the type of forest practices currently in use across Canada to address mitigation and adaptation. Most reports or studies were published in 2019 or later, with federal and provincial governments being the dominant actors in reporting and monitoring, research, and funding. Across the 15 terrestrial ecozones in Canada, forest practices linked to climate change were reported in 12 ecozones, with most practices reported in the Montane Cordillera located in western Canada. Common forest practices reported include fuel management, assisted migration, enhanced silvicultural activities, and carbon offset projects. We conclude that climate change adaptation/mitigation practices in Canada are in their early stages of implementation. Many practices remain in experimental stages (e.g., genetic trials) or are implemented at a relatively small scale in Canada (e.g., climate-based seed transfer and carbon reserves). The literature suggests that the most mainstream practices associated with climate change mitigation in Canada include tree planting for carbon sequestration and the designation of protected areas to enhance ecosystem resilience. We conclude that despite increasing reports linking climate change benefits with reported forest practices, the reporting in the scientific literature is scarce, poorly reported, and often not grounded in credible evidence. [ABSTRACT FROM AUTHOR]

• Substitution factors for forest products for the Canadian context were developed. • Substitution factors ranging from 0.51 to 0.91 tC/tC were found. • They will lead to more accurate assessments of the forest GHG mitigation potential. • These factors will help governments to manage forest and fight climate change. Evaluating the climate change mitigation potential of the forest sector requires a holistic approach based on forest carbon (C) sequestration, C storage in harvested wood products (HWP) and substitution on markets. High uncertainty is associated with substitution factors, that express avoided fossil greenhouse gas (GHG) emissions from the use of forest-based products in replacement of GHG-intensive materials and fossil fuels. Few studies have focused on the development of substitution factors in Canada, resulting in the use of unrepresentative generic data. Here, we provide a framework to reduce uncertainties related to substitution factors for primary wood products in a Canadian context. A life cycle assessment framework is used to quantify fossil GHG emissions for a baseline and a wood-intensive scenario. For solid product substitution, we focused on the construction sector and analyzed a range of innovative wood buildings with steel and reinforced concrete as alternative materials. We found non-weighted averages of 0.80 tC/tC for sawnwood and 0.81 tC/tC for panels. For energy substitution, we analyzed cases with different specifications on biomass product, facility type and alternative fossil fuel source in non-residential heat production and biofuel transportation sectors. We found a non-weighted average of 0.80 tC/tC for non-residential heat production and 0.51 tC/tC for biofuel transportation, that can be interpreted as 0.91 tC/tC for heavy fuel oil, 0.69 tC/tC for light fuel oil and 0.68 tC/tC for natural gas substitution. These results provide a benchmark for substitution factors in Canada, to help guide forest management strategies for climate change mitigation. [ABSTRACT FROM AUTHOR]

Managing forests and forest products has substantial potential to help mitigate climate change but the cost has not been extensively examined in Canada. We estimated the cost of seven forest-related mitigation strategies in Canada's 230 million hectares of managed forest, divided into 32 spatial units. For each strategy and spatial unit, we determined forest sector mitigation cost per tonne (t) using estimated impacts on forest sector greenhouse gas emissions and removals and net revenue. National cost curves showed that mitigation averaged 11.0 Mt CO2e·year-1 in 2015-2050 at costs below $50·t CO2e-1 for a strategy of increased recovery of harvested biomass, increased salvage, extraction of harvest residues for bioenergy, and increased production of longer lived products. We also examined national portfolios in which the strategy selected for each spatial unit (from among the seven examined) was chosen to maximize mitigation or minimize costs. At low levels of mitigation, portfolios chosen to minimize costs were much cheaper than those that maximized mitigation, but overall, they yielded less than half the total mitigation of the latter portfolios. Choosing strategies to maximize mitigation in 2015-2050 yielded an average of 16.5 Mt·year-1 at costs below $50·t CO2e-1. Our analysis suggests that forest-related strategies may be cost-effective choices to help achieve long-term emission reductions in Canada. [ABSTRACT FROM AUTHOR]

The success and rate of forest regeneration has consequences for sustainable forest management, climate change mitigation, and biodiversity, among others. Systematically monitoring forest regeneration over large and often remote areas is challenging. Remotely sensed data and associated analytical approaches have demonstrated consistent and transparent options for spatially-explicit characterization of vegetation return following disturbance. Moreover, time series of satellite imagery enable the establishment of spatially meaningful recovery baselines that can provide a benchmark for identifying areas that are either under- or over-performing relative to those baselines. This information allows for the investigation and/or prioritization of areas requiring some form of management intervention, including guiding tree planting initiatives. In this research, we assess recovery following stand replacing disturbances for the 650 Mha forested ecosystems of Canada for the period 1985–2017, wherein ~51 Mha of Canada's forested ecosystems were impacted by wildfire, and ~ 21 Mha were impacted by harvesting. For quantification of forest recovery, we implement the Years to Recovery or Y2R metric using Landsat time series data based on the Normalized Burn Ratio (NBR) to relate the number of years required for a pixel to return to 80% of its pre-disturbance NBR value. By the end of the analyzed period, 76% of areas impacted by wildfire were considered spectrally recovered compared to 93% of harvested areas. On average, we found that harvest areas had more rapid spectral recovery (mean Y2R = 6.1 years) than wildfire (mean Y2R = 10.6 years) and importantly, that Y2R varied by ecozone, disturbance type, pre-disturbance land cover, and latitude. We used airborne laser scanning data to assess whether pixels that were considered spectrally recovered had attained United Nations Food and Agricultural Organization benchmarks of canopy height (>5 m) and cover (>10%) across four geographic regions representing different forest types. Overall, 87% and 97% of recovered pixels sampled in harvests and wildfires, respectively, had achieved at least one of the benchmarks, with benchmarks of height more readily achieved than benchmarks of cover. By analyzing spatial patterns of Y2R, we identified areas that had significant positive or negative spatial clustering in their rate of spectral recovery. Approximately 3.5–4% of areas disturbed by wildfire or harvest had significant positive spatial clustering, indicative of slower spectral recovery rates; these areas were also less likely to have attained benchmarks of height and cover. Conversely, we identified significant negative spatial clustering for 0.94% of areas recovering from harvest and 1.93% of areas recovering from wildfire, indicative of spectral recovery that was more rapid than the ecozonal baseline. Herein, we demonstrated that remote sensing can provide spatial intelligence on the nature of disturbance-recovery dynamics in forested ecosystems over large areas and moreover, can retrospectively quantify and characterize historic forest recovery trends within the past three decades that have implications for forest management, climate change mitigation, and restoration initiatives in the near term. • Landsat time series monitored forest disturbance and recovery for 32 years across 650 Mha. • Harvests spectrally recovered more rapidly (6.1 years) than wildfire (10.6 years). • Lidar-derived benchmarks of canopy cover (>10%) and height (>5 m) used for validation. • 87% and 97% of recovered harvest and wildfire samples achieved one of the benchmarks. • Nationally, 3.5%–4% of wildfire and harvest areas had slower than expected recovery. [ABSTRACT FROM AUTHOR]

The demand for wood-based energy is foreseen to grow as energy and climate policies around the world promote the use of bioenergy for climate change mitigation. However, the carbon impacts of forest bioenergy range widely in the literature. The value-choices made on the response of forest management to bioenergy demand have a major influence on the results obtained from modeling exercises and may actually change the contribution of forest bioenergy from climate worsening to climate change mitigation. Despite their relevance, there is very little information, or transparency, as to the empirical basis by which these assumptions are chosen and evaluated against. This study aims to fill in this crucial knowledge gap through a mix of critical review, analysis of historical statistical data, and expert judgement. Several prominent studies reporting climate change mitigation from forest bioenergy in three countries are reviewed: Canada, Sweden, and Southeast USA. This analysis shows that the studies rely on assumptions that bioenergy demand will spur supply responses aimed at more efficient forest management and/or relative increases in forest area. Confronting literature assumptions with trends in historical data, we present the most extensive reality-check of bioenergy literature assumptions to date. We find that studies projecting a large role of forest bioenergy in climate change mitigation rely on assumptions that are too optimistic, at times outright unrealistic. We believe scientists could avoid the misinterpretation of their results and improve the policy relevance of their work by more transparent reporting of: i) value-laden assumptions, ii) their influence on the results, iii) the process and rationale behind such assumptions, especially distinguishing between assumptions that reflect incremental changes in management from assumptions requiring transformational change in several industrial sectors. • Accounted carbon benefits of forest bioenergy depend on underlying assumptions. • Forest bioenergy mitigates climate change only when additional biomass is produced. • Forest management responses assumed in the literature are overly optimistic. • Post Normal Science tools can help scientists avoid misinterpretation of results. • Scientists should better convey that model results are contingent on value-choices. [ABSTRACT FROM AUTHOR]