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Emissions-intensive, trade-exposed (EITE) industries must decarbonize to limit global warming to 1.5°C. This study explores how policy stringency and regional variability impact EITE industrial decarbonization. It uses Canada as a case study due to its heterogeneous industrial sector and high regional resource variability. The study has two scenarios: one with global climate action where the world pushes to limit warming to 1.5°C, and one where Canada acts to achieve net-zero emissions by 2050 and the rest of the world lags. The scenarios differ in three ways: the global price of oil, the pace of technological change for low emission technologies, and domestic climate policy. In the global action scenario, a carbon price of $430USD2020 was needed to achieve 75% decarbonization of EITE industries by 2050. In our global inaction scenario, EITE industries only decarbonize 25%, as domestic climate policy considered international competition and the risk of industrial shutdown. If competitiveness concerns persist as simulated in this scenario, Canada is highly unlikely to achieve deep industrial decarbonization by 2050. The results also show that regional variability plays a significant role in low emissions technology adoption. While all regions will need targeted innovation and commercialization support as well as market uptake mechanisms, we find that relative advantages and disadvantages in terms of resource availability and industrial mix play an important role in how regional decarbonization occurs. For instance, regions with inexpensive local fossil fuels and ready geology suitable for CO2 storage have a high uptake of carbon capture and storage. Regions with access to abundant hydroelectricity rely more on electrification as a decarbonization pathway. Regions with no relative resource advantages are at greater risk for industrial shutdown due to the higher cost of decarbonization. Achieving national deep decarbonization of EITE industries in Canada or elsewhere is highly unlikely without global climate action due to competitiveness concerns. Policymakers interested in addressing competitiveness concerns might do so either through policy mechanisms that support the uptake of low emission technologies, mechanisms that penalize regions without decarbonization policy, or both. Policymakers should consider relative regional advantages and disadvantages to EITE decarbonization by designing policies that account for industrial heterogeneity and regional resource availability. [ABSTRACT FROM AUTHOR]

The building sector is responsible for nearly 40% of the total global direct and indirect CO2 emissions. Urban green infrastructure, which includes features such as urban trees, vegetation, green roofs, and green facades, are examples of nature-based solutions often employed as municipal climate mitigation and adaptation strategies. This approach offers a range of cost-effective strategies for reducing municipal CO2 emissions and presents compelling public policy co-benefits such as improved urban livability and enhanced environmental conditions. For municipalities to confidently deploy these solutions at a scale necessary to achieve climate benefits, acquiring knowledge of quantifiable and demonstrated outcomes is an essential requirement. The objectives of this paper are to (1) provide a comprehensive analysis of the advantages and limitations of nature-based solutions (NBS) to address the challenge of reducing CO2 emissions; (2) evaluate existing design guidelines and policies as may be available across Canada, and that that support the of implementation of NBS in urban agglomerations; (3) identify knowledge gaps and research needs to address challenges to the implementation of NBS. In this review, suggestions and requirements as presented in these documents are examined while giving due consideration to the scientific evidence available in research papers. It was found that the adoption of NBS can contribute to carbon neutral communities through reduced building energy consumption and carbon sequestration. Supportive guidelines and policies have been developed, or are in development, to promote the implementation of NBS at the city scale, despite challenges in assessing, quantitatively, their impact due to uncertainties in data, methods, and scale. Nonetheless, existing research provides sufficient evidence to qualify the measures and suggestions outlined in the guidelines and policies described in this paper. [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]

• Soil organic carbon (SOC) stabilities were studied in two agroforestry systems. • We studied hedgerow and shelterbelt systems and their component land-uses (cropland vs forest). • The biological stability of SOC was higher in hedgerow than in shelterbelt system. • The biological stability of SOC was higher in cropland than in forest land-use. • Agroforestry system by land-use interactively affected the thermal stability of SOC. Agroforestry systems play important roles in carbon (C) sequestration in western Canada. However, the effect of agroforestry system type and their component land-uses (forested area and cropland) on soil organic C (SOC) stability is poorly understood. We studied SOC stability in surface soils from two agroforestry systems (shelterbelt system and hedgerow system) and their component land-uses (forested area and cropland) in western Canada. A 61-day laboratory incubation was used to assess SOC biological stability, and compared to thermal stability measured during ramped combustion. The shelterbelt system had a lower biological stability than the hedgerow system as indicated by the higher cumulative soil respiration and SOC loss during incubation. Cumulative respiration and SOC loss during incubation in the forested area was 1.63 and 1.57 times that in the cropland, indicating a lower SOC biological stability in the former. Thermal stability indicators, CO 2 -T 50 (the temperature at which half of the CO 2 is produced), DSC-T 50 (the temperature at which half of the exothermic energy of the SOC is released) and ROI (return on energy investment) were influenced by the interactive effects of the agroforestry system by land-use, while TG-T 50 (the temperature at which half of the exothermic mass is lost) and Ed (energy density) were influenced by land-use and the interactive effects of agroforestry system by land-use. Hedgerow cropland had a higher SOC thermal stability (higher TG-T 50) than the hedgerow forested area, while there was no difference among shelterbelt cropland, and the forested areas of shelterbelt and hedgerow system. We conclude that planting trees on agricultural land to form agroforestry systems alters SOC biological and thermal stabilities, and the hedgerow system may have a more stable SOC than the shelterbelt system, thus, maintaining the hedgerow system may enhance C stability, promote C sequestration and climate change mitigation. [ABSTRACT FROM AUTHOR]

Improved land stewardship is necessary for climate change mitigation. As such, actions are needed to increase carbon (C) sinks and reduce C emissions from land use activities. Residual materials with fertilizing capacity can be used to reconstruct severely degraded soils and recreate a sustainable vegetation cover, leading to reductions in atmospheric CO 2 levels. We studied the temporal dynamics of CO 2 sequestration potential in soils reconstructed with 1200 Mg ha−1 biosolids along a young chronosequence ranging from 0 to 7 years after initiating reclamation of a decommissioned asbestos mine in southern Québec, Canada. We measured in situ soil CO 2 fluxes, soil C pools and soil physicochemical properties. Since bacterial communities are highly responsive to soil physicochemical properties, we also analyzed both their diversity and community structure. The age since soil reclamation did not have a clear effect on soil properties, but it exerted greater control over soil C fluxes and soil bacterial community diversity and structure. Our results suggest large C fluxes to the atmosphere within the first year following soil reconstruction, but soils constitute a stable C pool thereafter. [ABSTRACT FROM AUTHOR]

Quantitative assessment of Canada's boreal forest mitigation potential is not yet possible, though the range of mitigation activities is known, requirements for sound analyses of options are increasingly understood, and there is emerging recognition that biogeophysical effects need greater attention. Use of a systems perspective highlights trade-offs between activities aimed at increasing carbon storage in the ecosystem, increasing carbon storage in harvested wood products (HWPs), or increasing the substitution benefits of using wood in place of fossil fuels or more emissions-intensive products. A systems perspective also suggests that erroneous conclusions about mitigation potential could result if analyses assume that HWP carbon is emitted at harvest, or bioenergy is carbon neutral. The greatest short-run boreal mitigation benefit generally would be achieved by avoiding greenhouse gas emissions; but over the longer run, there could be significant potential in activities that increase carbon removals. Mitigation activities could maximize landscape carbon uptake or maximize landscape carbon density, but not both simultaneously. The difference between the two is the rate at which HWPs are produced to meet society's demands, and mitigation activities could seek to delay or reduce HWP emissions and increase substitution benefits. Use of forest biomass for bioenergy could also contribute though the point in time at which this produces a net mitigation benefit relative to a fossil fuel alternative will be situation-specific. Key knowledge gaps exist in understanding boreal mitigation strategies that are robust to climate change and how mitigation could be integrated with adaptation to climate change. [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.)

It is generally accepted that land use and land management practices impact climate change through sequestration of carbon in soils, but modulation of surface energy budget can also be important. Using Landsat data to characterize cropland albedos in Canada's three prairie soil zones, this study estimates the atmospheric carbon equivalent drawdown of albedo radiative forcing for three management practices: 1) moving from conventional tillage to no-till, 2) eliminating summer fallow in crop rotations, and 3) growing crops with higher albedos. In a 50-year time horizon, conversion from conventional tillage to no-till results in a total equivalent atmospheric C O 2 (C O 2 -eq) drawdown of 1.0–1.5 kg m − 2 , and conversion from summer fallow to crops results in C O 2 -eq drawdown of 1.1–2.4 kg m − 2 . Conversion of summer fallow to crops results in different magnitudes of C O 2 -eq drawdown depending on specific crops. Lentils, peas, and canola have relatively higher albedo than that of spring wheat and flax; hence, a larger magnitude of C O 2 -eq drawdown results when they replace summer fallow in the rotation. For the management changes from 1990 to 2019 for the whole Canadian Prairies, albedo changes induced a C O 2 -eq drawdown of about 179.3 ± 20.9 Tg due to increased area of no-till, and 101.6 ± 9.5 Tg due to reduced area under fallow. The study shows that the magnitudes of C O 2 -eq drawdown due to albedo change are comparable to that due to soil carbon sequestration. Therefore, it is important to account for cropland albedo changes in assessing the potential of agricultural management practices to mitigate climate change. • Agricultural practices modify surface albedos and induce radiative forcing. • Albedo radiative forcing is assessed using carbon equivalent metrics. • Reducing summer fallow and tillage intensity induces negative radiative forcing. • Large scale conversion of crops causes albedo radiative forcing. • Cropland albedo change should be considered in climate change mitigation. [ABSTRACT FROM AUTHOR]

Copyright of Forestry Chronicle is the property of Canadian Institute of Forestry 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.)

• Tree planting on degraded land has been identified as an effective carbon capture strategy. • Unclear how associated restoration treatment influence carbon sequestration. • Tree carbon pool increased with greater restoration effort. • Existing site characteristics influence carbon sequestration potential. • Land managers must balance restoration cost with carbon sequestration. Landscape carbon storage is a key component of climate change mitigation. Tree planting on degraded land has been identified as an effective carbon capture strategy, but it is unclear how various associated restoration treatments influence carbon sequestration. In this study, we measured carbon pools in jack pine (Pinus banksiana Lamb.) stands subject to different restoration treatments within severely damaged upland areas in the metal mining region of Sudbury, Ontario, Canada. Treatments included: i) soil amendment (liming, fertilizing and grass/legume seeding) followed by jack pine planting, ii) jack pine planting alone, iii) soil amendment only, and iv) untreated plots with some natural regeneration as a result of improving air quality in the region. Twenty-four years after the initial treatments, we measured the carbon storage in coarse and fine woody debris, herbs, shrubs, forest floor (LFH), mineral soil, and trees. The carbon pool in planted trees was 1.5 times higher in plots when soil amendments were applied. This increase in the tree carbon pool was the result of greater carbon sequestration per individual jack pine tree rather than changes in tree density or arrival of new species. Similarly, naturally regenerated white birch (Betula papyrifera Marshall) in the amended plots stored 1.7 times more carbon than white birch in the untreated plots. Tree planting proved essential on this landscape with natural tree regeneration rates very low even 50 years after local pollution was massively reduced. However, tree planting surprisingly did not significantly affect total carbon storage in these exposed upland sites. Total ecosystem carbon varied from 21.4 Mg ha−1 to 124.5 Mg ha−1 across all plots (mean of 67.6 ± 4.8 Mg ha−1) but no statistically significant differences were observed among the treatments. Soil organic carbon (SOC) proved to be the largest carbon pool across plots and stored on average 66% of total ecosystem carbon. However, at this early stage the restoration treatments had no influence on SOC pools on this highly degraded landscape, which still appears to be severely affected by ongoing erosion of surface soil and metal contamination. The restoration treatment also did not significantly affect the understory or downed woody debris carbon pools. This study demonstrates that the current restoration treatments used in Sudbury do influence the amount of carbon sequestrated mainly through tree restoration on this industrially degraded landscape, but long-term storage potential is still limited by poor soil conditions. [ABSTRACT FROM AUTHOR]

Shelterbelts have been planted around the world for many reasons. Recently, due to increasing awareness of climate change risks, shelterbelt agroforestry systems have received special attention because of the environmental services they provide, including their greenhouse gas (GHG) mitigation potential. This paper aims to discuss shelterbelt history in Canada, and the environmental benefits they provide, focusing on carbon sequestration potential, above- and below-ground. Shelterbelt establishment in Canada dates back to more than a century ago, when their main use was protecting the soil, farm infrastructure and livestock from the elements. As minimal-and no-till systems have become more prevalent among agricultural producers, soil has been less exposed and less vulnerable to wind erosion, so the practice of planting and maintaining shelterbelts has declined in recent decades. In addition, as farm equipment has grown in size to meet the demands of larger landowners, shelterbelts are being removed to increase efficiency and machine maneuverability in the field. This trend of shelterbelt removal prevents shelterbelt's climate change mitigation potential to be fully achieved. For example, in the last century, shelterbelts have sequestered 4.85 Tg C in Saskatchewan. To increase our understanding of carbon sequestration by shelterbelts, in 2013, the Government of Canada launched the Agricultural Greenhouse Gases Program (AGGP). In five years, 27 million dollars were spent supporting technologies and practices to mitigate GHG release on agricultural land, including understanding shelterbelt carbon sequestration and to encourage planting on farms. All these topics are further explained in this paper as an attempt to inform and promote shelterbelts as a climate change mitigation tool on agricultural lands. [ABSTRACT FROM AUTHOR]