Carolyn E Smyth

Natural Resources Canada | NRCan · Pacific Forestry Centre

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...

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. Mitigation benefits through the use of forest products are affected by product lifecycles, which determine the duration of carbon storage in wood products and substitution benefits where em...

We estimate the mitigation potential of local use of bioenergy from harvest residues for the 2.3 × 106 km2 (232 Mha) of Canada's managed forests from 2017 to 2050 using three models: Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3), a harvested wood products (HWP) model that estimates bioenergy emissions, and a model of emission substit...

The Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3), version 1.2, is a stand- and landscape-level modeling framework that can be used to simulate the dynamics of all forest carbon pools required under the United Nations Framework Convention on Climate Change and the Kyoto Protocol. It is compliant with the carbon estimation methods out...

Background The potential contributions from forest-based greenhouse gas (GHG) mitigation actions need to be quantified to develop pathways towards net negative emissions. Here we present results from a comparative analysis that examined mitigation options for British Columbia’s forest sector. Mitigation scenarios were evaluated using a systems per...

This article summarizes a ten-year plan for forest carbon science that was developed in a collaborative effort with the forest carbon science and policy community in Canada. Building on the research progress since the first plan, the updated Blueprint outlines key priorities, goals, and visions for forest carbon research over the next decade. Here...

In 2012, A Blueprint for Forest Carbon Science in Canada: 2012–2020 was published to guide policy and research and to support Canada's obligations for climate change mitigation and adaptation, sustainable forest management, and international reporting. Over the past decade, the body of scientific research focused on forest carbon dynamics in Canada...

This Blueprint outlines the forest carbon science priorities needed to support policy over the next decade. The science priorities were developed in collaboration with the forest carbon science and policy communities across Canada (governments, universities, environmental groups, and industry associations).

The objectives were to identify supply chains of salvage biomass for a selection of mills and communities, and to assess GHG implications of using salvage biomass for bioenergy or liquid transportation fuels. This study examined the forest ecosystem C balance, C use in bioenergy or biofuels, and substitution benefits from avoiding fossil-based ene...

Having recently experienced the three worst wildfire seasons in British Columbia's history in 2017, 2018 and 2021, and anticipating more severe impacts in the future, a key Carbon (C) research priority is to develop reliable models to explore options and identify a portfolio of regionally differentiated solutions for wildfire and forest management....

Background: There is strong evidence that wood-based products are typically associated with lower fossil-based emissions over their lifecycle than functionally equivalent products made from other materials. However, the potential impact of large-scale material substitution at the market level remains challenging to quantify and is subject to assump...

Alongside the steep reductions needed in fossil fuel emissions, natural climate solutions (NCS) represent readily deployable options that can contribute to Canada’s goals for emission reductions. We estimate the mitigation potential of 24 NCS related to the protection, management, and restoration of natural systems that can also deliver numerous co...

Managing forests and forest products to help mitigate climate change was quantified in three coordinated studies involving six regions within North America. Each country-specific study examined several mitigation scenarios in a comparative analysis, using harmonized tools with site-specific data and a systems approach that included forest ecosyste...

KEY FINDINGS 1. Net uptake of 217 teragrams of carbon (Tg C) per year by the forest sector in North America is well documented and has persisted at about this level over the last decade. The strength of net carbon uptake varies regionally, with about 80% of the North American forest carbon sink occurring within the United States (high confidence, v...

Executive summary Forests have multiple roles, but the role of forests in climate change mitigation has become increasingly important due to the urgent need to reduce climate change impacts. Forests remove carbon dioxide from the atmosphere via photosynthesis, and store carbon in biomass and soil. When forests are harvested, part of the carbon is r...

Background: We determine the potential of forests and the forest sector to mitigate greenhouse gas (GHG) emissions by changes in management practices and wood use for two regions within Canada's managed forest from 2018 to 2050. Our modeling frameworks include the Carbon Budget Model of the Canadian Forest Sector, a framework for harvested wood pr...

Background: United States forests can contribute to national strategies for greenhouse gas reductions. The objective of this work was to evaluate forest sector climate change mitigation scenarios from 2018 to 2050 by applying a systems-based approach that accounts for net emissions across four interdependent components: (1) forest ecosystem, (2) l...

Increasing combustion of woody biomass for electricity has raised concerns and produced conflicting statements about impacts on atmospheric greenhouse gas (GHG) concentrations, climate, and other forest values such as timber supply and biodiversity. The purposes of this concise review of current literature are to (1) examine impacts on net GHG emis...

The Paris Agreement of the United Nation Framework Convention on Climate Change calls for a balance of anthropogenic greenhouse emissions and removals in the latter part of this century. Mexico indicated in its Intended Nationally Determined Contribution and its Climate Change Mid-Century Strategy that the land sector will contribute to meeting GHG...

Managing forests to increase carbon sequestration or reduce carbon emissions and using wood products and bioenergy to store carbon and substitute for other emission-intensive products and fossil fuel energy have been considered effective ways to tackle climate change in many countries and regions. The objective of this study is to examine the clima...

Interest in forest biomass in Canada has resulted in a need to quantify and project, regionally and nationally, the availability of this resource. The motivation behind this activity is generally to evaluate the climate change mitigation potential of bio-energy as a substitute for fossil fuels, or in the increased use of wood products to substitute...

http://pics.uvic.ca/events/managing-bc%E2%80%99s-forest-sector-mitigate-climate-change-future-options-emissions-reductions

Forests play an important role in regulating climate. Changes in how forests and harvested wood products are managed can also offer substantial opportunities to mitigate climate change by reducing greenhouse gases (GHG) emissions or increasing carbon removals from the atmosphere. To evaluate the credibility and public acceptability of such forest...

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 determi...

Aims and Methods We measured changes in mass and in carbon (C), nitrogen (N) and phosphorus (P) concentrations and content of surface-placed and buried wood blocks decomposing over 12 years at 21 sites across Canada to evaluate the influence of the environment on C, N, and P dynamics. Results and Conclusions Carbon decomposition over time was best...

The main objective of this study was to estimate past and future dynamics of forest carbon pools in South Korea, as classified by the Intergovernmental Panel on Climate Change (IPCC) Good Practice Guidance (GPG) and to test the Carbon Budget Model of the Canadian Forest Sector 3 (CBM-CFS3). Inventory data required in CBM-CFS3 were extracted from Ko...

Following the introduction, Chapter 2 provides an overview of mitigation in the forest sector, addressing the handling of forests under UNFCCC. Chapters 3 to 5 focus on forest-based mitigation options – afforestation, reforestation, REDD+ and forest management – and Chapters 6 and 7 focus on wood-product based options – wood energy and green buildi...

Long-term rates of litter decay have been shown to be primarily influenced by temperature, moisture and litter quality. However, while decomposition is a biological process, the relative importance of microbial communities and other soil chemistry factors is not well understood. Our analysis examined long-term litter decay parameters, microbial com...

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...

Assessing the uncertainties in the estimates obtained from forest carbon budget models used for national and international reporting is essential, but model evaluations are rarely conducted mainly because of lack of appropriate, independent ground plot data sets. Ecosystem carbon stock estimates for 696 ground plots from Canada's new National Fores...

[1] Canada's forests play an important role in the global carbon cycle through carbon (C) storage and C exchange with the atmosphere. While estimates of aboveground biomass have been improving, little is known about belowground C storage in root biomass. Here we estimated the contribution of roots to the C budget of Canada's 2.3 × 106 km2 managed f...

Canada’s managed boreal forest, 54% of the nation’s total boreal forest area, stores 28 Pg carbon (C) in biomass, dead organic matter, and soil pools. The net C balance is dominated by the difference of two large continuous fluxes: C uptake (net primary production) and release during decomposition (heterotrophic respiration). Additional releases of...

The estimation of past and future forest carbon (C) dynamics in European countries is a challenging task due to complex and varying silvicultural systems, including uneven-aged forest management, and incomplete inventory data time series. In this study, we tested the use of the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) in Italy,...

Soil carbon (C) stocks are large C reservoirs that are characterized by turnover times of decades to centuries. The ability to predict how long C remains in soils requires an understanding of soil decom- position and the influence of climate change on destabilization processes. This study examined forest soil decomposition and quantified the influence...

Background/Question/Methods Forests remove carbon (C) from the atmosphere and store it in the form of biomass, dead organic matter and soil, while also providing other ecosystem services and meeting society’s demands for products such as timber, wood fiber, and energy. Based on data from Canada’s National Forest Carbon Monitoring, Accounting, and...

Canada’s managed boreal forest, 54% of the nation’s total boreal forest area, stores 28 Pg carbon (C) in biomass, dead organic matter, and soil pools. The net C balance is dominated by the difference of two large continuous fluxes: C uptake (net primary production) and release during decomposition (heterotrophic respiration). Additional releases of...

Background/Question/Methods Canada fulfills its international obligation to report forest-related greenhouse gas emissions and removals using the National Forest Carbon Monitoring, Accounting and Reporting System (NFCMARS). The core model of the NFCMARS is the CBM-CFS3 which combines forest inventories, empirical yield tables developed from sample...

Afforestation with short-rotation coppice (SRC) willow plantations for the purpose of producing bioenergy feedstock was contemplated as one potential climate change mitigation option. The objectives of this study were to assess the magnitude of this mitigation potential by addressing: (i) the land area potentially available for SRC systems in the p...

Decomposition of plant detritus and humified organic matter in terrestrial ecosystems is a primary source of atmospheric carbon dioxide (CO2), yet the dynamics of decomposition are not well understood, particularly their response to climate change. The Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) presently includes a sub-model to si...

Canada's forests play an important role in the global carbon (C) cycle because of their large and dynamic C stocks. Detailed monitoring of C exchange between forests and the atmosphere and improved understanding of the processes that affect the net ecosystem exchange of C are needed to improve our understanding of the terrestrial C budget. We estim...

Decomposition of plant detritus and heterotrophic respiration have been demonstrated to be affected by climate, litter type and soil biota. Clearcut harvest affects site temperature and water balance and theoretically in situ measurements of soil microenvironment and models which include them should better account for variation in soil C fluxes amo...

Litter decay in early and midphases of decomposition have been shown to highly influenced by climate and substrate quality, however factors affecting decay during the late semi-stable phase are less well understood. The Canadian Intersite Decomposition Experiment (CIDET) was established in 1992 with the objective of providing data on the long-term...

Slowing or even cessation of litter decomposition with time is well-known, but there is insufficient understanding of the chemical changes that contribute to increasing recalcitrance. Samples from the Canadian Intersite Decomposition Experiment (CIDET) were used to determine 6-year chemical changes for all 11 litters from a site with rapid initial...

Decreasing uncertainty in CBM-CFS3 estimates of forest soil C sources and sinks through use of long-term data from the Canadian Intersite Decomposition Experiment. https://cfs.nrcan.gc.ca/publications?id=31205

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 carbo...

We present a case study approach to assessing the sensitivity of the dead organic matter sub-module of the operational-scale version of the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) to variation in model parameters controlling inputs to and throughput in this module. Parameters examined included those controlling biomass growth a...

Soil respiration includes CO2 respired by plant roots and by soil biota decomposing plant detritus. Detrital C stocks and fluxes are being studied at 16 sites at 7 stations of the Fluxnet Canada Research Network, including paired mature and clearcut forest sites at 5 upland stations (BC, SK, ON, QC, NB). All sites were instrumented for in situ meas...

Climate and substrate quality have been shown to be key determinants of rates of litter decomposition, though other site factors can be important under certain conditions. The Canadian Intersite Decomposition Experiment (CIDET) was established in 1992 with the objective of providing data on the long-term rates of litter decomposition and nutrient m...

A litter decomposition study was established in 16 sites at 7 stations of the Fluxnet Canada Research Network. These sites included paired mature and clearcut forest sites at 5 upland stations (BC, SK, ON, QC, NB) as well as one site at each of two wetland stations (AW, QW) . All sites are instrumented for in situ measurements of soil moisture and...