Prioritising agri-environment options for greenhouse gas mitigation

Purpose This paper aims to assess agri-environment (AE) scheme options on cultivated agricultural land in England for their impact on agricultural greenhouse gas (GHG) emissions. It considers both absolute emissions reduction and reduction incorporating yield decrease and potential production displacement. Similarities with Ecological Focus Areas (EFAs) introduced in 2015 as part of the post-2014 Common Agricultural Policy reform, and their potential impact, are considered. Design/methodology/approach A life-cycle analysis approach derives GHG emissions for 18 key representative options. Meta-modelling is used to account for spatial environmental variables (annual precipitation, soil type and erosion risk), supplementing the Intergovernmental Panel on Climate Change methodology. Findings Most options achieve an absolute reduction in GHG emissions compared to an existing arable crop baseline but at the expense of removing land from production, risking production displacement. Soil and water protection options designed to reduce soil erosion and nitrate leaching decrease GHG emissions without loss of crop yield. Undersown spring cereals support decreased inputs and emissions per unit of crop yield. The most valuable AE options identified are included in the proposed EFAs, although lower priority is afforded to some. Practical implications Recommendations are made where applicable to modify option management prescriptions and to further reduce GHG emissions. Originality/value This research is relevant and of value to land managers and policy makers. A dichotomous key summarises AE option prioritisation and supports GHG mitigation on cultivated land in England. The results are also applicable to other European countries.

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Informing urban climate planning with high resolution data: the Hestia fossil fuel CO2 emissions for Baltimore, Maryland

10.21203/rs.3.rs-16517/v3 ◽

2020 ◽

Author(s):

Geoffrey Scott Roest ◽

Kevin R Gurney ◽

Scot M Miller ◽

Jianming Liang

Keyword(s):

Greenhouse Gas ◽

Fossil Fuel ◽

Ghg Emissions ◽

Point Sources ◽

The Self ◽

Greenhouse Gas Mitigation ◽

Electricity Production ◽

Ghg Mitigation ◽

High Resolution Data ◽

Atmospheric Monitoring

Abstract Background: Cities contribute more than 70% of global anthropogenic carbon dioxide (CO2) emissions and are leading the effort to reduce greenhouse gas (GHG) emissions through sustainable planning and development. However, urban greenhouse gas mitigation often relies on self-reported emissions estimates that may be incomplete and unverifiable via atmospheric monitoring of GHGs. We present the Hestia Scope 1 fossil fuel CO2 (FFCO2) emissions for the city of Baltimore, Maryland – a gridded annual and hourly emissions data product for 2010 through 2015 (Hestia-Baltimore v1.6). We also compare the Hestia-Baltimore emissions to overlapping Scope 1 FFCO2 emissions in Baltimore’s self-reported inventory for 2014. Results: The Hestia-Baltimore emissions in 2014 totaled 1487.3 kt C (95% confidence interval of 1,158.9 – 1,944.9 kt C), with the largest emissions coming from onroad (34.2% of total city emissions), commercial (19.9%), residential (19.0%), and industrial (11.8%) sectors. Scope 1 electricity production and marine shipping were each generally less than 10% of the city’s total emissions. Baltimore’s self-reported Scope 1 FFCO2 emissions included onroad, natural gas consumption in buildings, and some electricity generating facilities within city limits. The self-reported Scope 1 FFCO2 total of 1,182.6 kt C was similar to the sum of matching emission sectors and fuels in Hestia-Baltimore v1.6. However, 20.5% of Hestia-Baltimore’s emissions were in sectors and fuels that were not included in the self-reported inventory. Petroleum use in buildings were omitted and all Scope 1 emissions from industrial point sources, marine shipping, nonroad vehicles, rail, and aircraft were categorically excluded.Conclusions: The omission of petroleum combustion in buildings and categorical exclusions of several sectors resulted in an underestimate of total Scope 1 FFCO2 emissions in Baltimore’s self-reported inventory. Accurate Scope 1 FFCO2 emissions, along with Scope 2 and 3 emissions, are needed to inform effective urban policymaking for system-wide GHG mitigation. We emphasize the need for comprehensive Scope 1 emissions estimates for emissions verification and measuring progress towards Scope 1 GHG mitigation goals using atmospheric monitoring.

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NDCmitiQ v1.0.0: a tool to quantify and analyse greenhouse gas mitigation targets

Geoscientific Model Development ◽

10.5194/gmd-14-5695-2021 ◽

2021 ◽

Vol 14 (9) ◽

pp. 5695-5730

Author(s):

Annika Günther ◽

Johannes Gütschow ◽

Mairi Louise Jeffery

Keyword(s):

Land Use ◽

Greenhouse Gas ◽

Ghg Emissions ◽

Global Scale ◽

Greenhouse Gas Mitigation ◽

Ghg Mitigation ◽

Data Set ◽

Wide Range ◽

The Usa ◽

External Time

Abstract. Parties to the Paris Agreement (PA, 2015) outline their planned contributions towards achieving the PA temperature goal to “hold […] the increase in the global average temperature to well below 2 ∘C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5 ∘C” (Article 2.1.a, PA) in their nationally determined contributions (NDCs). Most NDCs include targets to mitigate national greenhouse gas (GHG) emissions, which need quantifications to assess i.a. whether the current NDCs collectively put us on track to reach the PA temperature goals or the gap in ambition to do so. We implemented the new open-source tool “NDCmitiQ” to quantify GHG mitigation targets defined in the NDCs for all countries with quantifiable targets on a disaggregated level and to create corresponding national and global emissions pathways. In light of the 5-year update cycle of NDCs and the global stocktake, the quantification of NDCs is an ongoing task for which NDCmitiQ can be used, as calculations can easily be updated upon submission of new NDCs. In this paper, we describe the methodologies behind NDCmitiQ and quantification challenges we encountered by addressing a wide range of aspects, including target types and the input data from within NDCs; external time series of national emissions, population, and GDP; uniform approach vs. country specifics; share of national emissions covered by NDCs; how to deal with the Land Use, Land-Use Change and Forestry (LULUCF) component and the conditionality of pledges; and establishing pathways from single-year targets. For use in NDCmitiQ, we furthermore construct an emissions data set from the baseline emissions provided in the NDCs. Example use cases show how the tool can help to analyse targets on a national, regional, or global scale and to quantify uncertainties caused by a lack of clarity in the NDCs. Results confirm that the conditionality of targets and assumptions about economic growth dominate uncertainty in mitigated emissions on a global scale, which are estimated as 48.9–56.1 Gt CO2 eq. AR4 for 2030 (10th/90th percentiles, median: 51.8 Gt CO2 eq. AR4; excluding LULUCF and bunker fuels; submissions until 17 April 2020 and excluding the USA). We estimate that 77 % of global 2017 emissions were emitted from sectors and gases covered by these NDCs. Addressing all updated NDCs submitted by 31 December 2020 results in an estimated 45.6–54.1 Gt CO2 eq. AR4 (median: 49.6 Gt CO2 eq. AR4, now including the USA again) and increased coverage.

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Frameworks for reducing greenhouse gas (GHG) emissions from municipal solid waste in Oman

Management of Environmental Quality An International Journal ◽

10.1108/meq-11-2019-0231 ◽

2020 ◽

Vol 31 (4) ◽

pp. 945-960 ◽

Cited By ~ 1

Author(s):

Tariq Umar

Keyword(s):

Carbon Dioxide ◽

Municipal Solid Waste ◽

Greenhouse Gas ◽

Solid Waste ◽

Ghg Emissions ◽

Intergovernmental Panel ◽

Content Type ◽

Per Capita ◽

Carbon Dioxide Equivalent ◽

Practical Implications

PurposeThe Gulf Cooperation Council member countries not only generate the highest quantity of municipal solid waste (MSW) per capita when compared globally, but also in most of these countries, such waste is just dumped at different landfill stations. In Oman, the total quantity of MSW stood at 2.0 million tons per year. The emission from this waste is estimated at 2,181,034 tons/year (carbon dioxide equivalent). This article attempts to develop frameworks that considered landfilling, composting and recycling of MSW.Design/methodology/approachTo know the composition of the municipal solid waste in Oman, a quantitative research method was employed. The greenhouse gas (GHG) emissions from MSWM in this study focus on three major gases, CO2, CH4 and N2O. The Intergovernmental Panel on Climate Change (IPCC) 2006 model is used to calculate GHG emissions from landfills and composting (IPCC, 2006). Four frameworks – baseline F0, framework F1, framework F2 and framework F3 – are outlined in this paper. The F0 represents the current situation of the MSW in which most of the waste goes to landfills and dumpsites. In F1, improved MSW collection service and landfilling are incorporated and open burning is restricted. The F2 considered landfilling and composting, while F3 is based on landfilling, composting and recycling.FindingsThe framework F2, which proposes the composting process for the organic waste which normally goes to landfills, results in the reduction of emissions by 40% as compared to landfill practice. Similarly, the samples of MSW collected in Oman show a good amount of recycling waste. The framework F3, which considers the landfill, composting and recycling, reduced the total GHG emissions from 2,181,034 tons/year to 1,427,998 tons/year (carbon dioxide equivalent), representing a total reduction of 35% in emissions.Research limitations/implicationsDifferent values such as CH4 correction factor, the fraction of degradable organic carbon and the fraction of DOC used to determine the GHG emissions from MSW considering landfilling, composting and recycling based on the IPPC model and existing literature review. The actual determination of these values based on the Oman conditions may result in more accurate emissions from MSW in Oman.Practical implicationsDifferent frameworks suggested in this research have different practical implications; however, the final framework F3, which produces fewer emissions, required a material recovery facility to recycle the MSW in Oman. For framework F3, it is important that the residents in Oman have enough knowledge and willingness to do the waste segregation at the household level. Apparently, such knowledge and willingness need to be determined through a separate study.Originality/valueThe frameworks F2 and F3 are considered to be more suitable solutions compared to the current practices for Oman and other gulf countries to reduce its per capita emissions from MSW and protect its local environment. There is a potential for further work that needs to explore the possible solutions to implement the suggested frameworks.

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Soil greenhouse gas fluxes from tropical coastal wetlands and alternative agricultural land uses

Biogeosciences ◽

10.5194/bg-18-5085-2021 ◽

2021 ◽

Vol 18 (18) ◽

pp. 5085-5096

Author(s):

Naima Iram ◽

Emad Kavehei ◽

Damien T. Maher ◽

Stuart E. Bunn ◽

Mehran Rezaei Rashti ◽

...

Keyword(s):

Salt Marsh ◽

Greenhouse Gas ◽

Coastal Wetlands ◽

Agricultural Land ◽

Ghg Emissions ◽

Climatic Conditions ◽

Land Uses ◽

Ghg Mitigation ◽

Tropical Regions ◽

Ghg Fluxes

Abstract. Coastal wetlands are essential for regulating the global carbon budget through soil carbon sequestration and greenhouse gas (GHG – CO2, CH4, and N2O) fluxes. The conversion of coastal wetlands to agricultural land alters these fluxes' magnitude and direction (uptake/release). However, the extent and drivers of change of GHG fluxes are still unknown for many tropical regions. We measured soil GHG fluxes from three natural coastal wetlands – mangroves, salt marsh, and freshwater tidal forests – and two alternative agricultural land uses – sugarcane farming and pastures for cattle grazing (ponded and dry conditions). We assessed variations throughout different climatic conditions (dry–cool, dry–hot, and wet–hot) within 2 years of measurements (2018–2020) in tropical Australia. The wet pasture had by far the highest CH4 emissions with 1231±386 mgm-2d-1, which were 200-fold higher than any other site. Dry pastures and sugarcane were the highest emitters of N2O with 55±9 mgm-2d-1 (wet–hot period) and 11±3 mgm-2d-1 (hot-dry period, coinciding with fertilisation), respectively. Dry pastures were also the highest emitters of CO2 with 20±1 gm-2d-1 (wet–hot period). The three coastal wetlands measured had lower emissions, with salt marsh uptake of -0.55±0.23 and -1.19±0.08 gm-2d-1 of N2O and CO2, respectively, during the dry–hot period. During the sampled period, sugarcane and pastures had higher total cumulative soil GHG emissions (CH4+N2O) of 7142 and 56 124 CO2-eqkgha-1yr-1 compared to coastal wetlands with 144 to 884 CO2-eqkgha-1yr-1 (where CO2-eq is CO2 equivalent). Restoring unproductive sugarcane land or pastures (especially ponded ones) to coastal wetlands could provide significant GHG mitigation.

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Informing urban climate planning with high resolution data: the Hestia fossil fuel CO2 emissions for Baltimore, Maryland

10.21203/rs.3.rs-16517/v4 ◽

2020 ◽

Author(s):

Geoffrey Scott Roest ◽

Kevin R Gurney ◽

Scot M Miller ◽

Jianming Liang

Keyword(s):

Greenhouse Gas ◽

Fossil Fuel ◽

Ghg Emissions ◽

Point Sources ◽

The Self ◽

Greenhouse Gas Mitigation ◽

Electricity Production ◽

Ghg Mitigation ◽

High Resolution Data ◽

Atmospheric Monitoring

Abstract Background Cities contribute more than 70% of global anthropogenic carbon dioxide (CO2) emissions and are leading the effort to reduce greenhouse gas (GHG) emissions through sustainable planning and development. However, urban greenhouse gas mitigation often relies on self-reported emissions estimates that may be incomplete and unverifiable via atmospheric monitoring of GHGs. We present the Hestia Scope 1 fossil fuel CO2 (FFCO2) emissions for the city of Baltimore, Maryland – a gridded annual and hourly emissions data product for 2010 through 2015 (Hestia-Baltimore v1.6). We also compare the Hestia-Baltimore emissions to overlapping Scope 1 FFCO2 emissions in Baltimore’s self-reported inventory for 2014. Results The Hestia-Baltimore emissions in 2014 totaled 1487.3 kt C (95% confidence interval of 1,158.9 – 1,944.9 kt C), with the largest emissions coming from onroad (34.2% of total city emissions), commercial (19.9%), residential (19.0%), and industrial (11.8%) sectors. Scope 1 electricity production and marine shipping were each generally less than 10% of the city’s total emissions. Baltimore’s self-reported Scope 1 FFCO2 emissions included onroad, natural gas consumption in buildings, and some electricity generating facilities within city limits. The self-reported Scope 1 FFCO2 total of 1,182.6 kt C was similar to the sum of matching emission sectors and fuels in Hestia-Baltimore v1.6. However, 20.5% of Hestia-Baltimore’s emissions were in sectors and fuels that were not included in the self-reported inventory. Petroleum use in buildings were omitted and all Scope 1 emissions from industrial point sources, marine shipping, nonroad vehicles, rail, and aircraft were categorically excluded.Conclusions The omission of petroleum combustion in buildings and categorical exclusions of several sectors resulted in an underestimate of total Scope 1 FFCO2 emissions in Baltimore’s self-reported inventory. Accurate Scope 1 FFCO2 emissions, along with Scope 2 and 3 emissions, are needed to inform effective urban policymaking for system-wide GHG mitigation. We emphasize the need for comprehensive Scope 1 emissions estimates for emissions verification and measuring progress towards Scope 1 GHG mitigation goals using atmospheric monitoring.

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Evaluating greenhouse gas mitigation practices in livestock systems: an illustration of a whole-farm approach

The Journal of Agricultural Science ◽

10.1017/s0021859609008764 ◽

2009 ◽

Vol 147 (4) ◽

pp. 367-382 ◽

Cited By ~ 26

Author(s):

A. A. STEWART ◽

S. M. LITTLE ◽

K. H. OMINSKI ◽

K. M. WITTENBERG ◽

H. H. JANZEN

Keyword(s):

Greenhouse Gas ◽

Management Practices ◽

Ghg Emissions ◽

Farming Systems ◽

Greenhouse Gas Mitigation ◽

Intergovernmental Panel ◽

Management Scenario ◽

Southern Alberta ◽

Agricultural Emissions ◽

Reduce Emissions

SUMMARYAs agriculture contributes about 0·08 of Canada's greenhouse gas (GHG) emissions, reducing agricultural emissions would significantly decrease total Canadian GHG output. Evaluating mitigation practices is not always easy because of the complexity of farming systems in which one change may affect many processes and associated emissions. The objective of the current study was to compare the effects of selected management practices on net whole-farm emissions, expressed in CO2equivalents (CO2e) from a beef production system, as estimated for hypothetical farms at four disparate locations in western Canada. Whole-farm emissions (t CO2e) per unit of protein output (t) of 11 management systems (Table 2) were compared for each farm using a model based, in part, on Intergovernmental Panel on Climate Change (IPCC) equations. Compared with the baseline management scenario, maintaining cattle on alfalfa-grass pastures showed the largest decrease (0·53–1·08 t CO2e/t protein) in emissions for all locations. Feeding lower quality forage over winter showed the greatest increase in emissions per unit protein on the southern Alberta (S.AB) and northern Alberta (N.AB) farms, with increases of 1·36 and 2·22 t CO2e/t protein, respectively. Eliminating the fertilization of forages resulted in the largest increase (4·20 t CO2e/t protein) in emissions per unit protein on the Saskatchewan (SK) farm, while reducing the fertilizer rate by half for all crops showed the largest increase (11·40 t CO2e/t protein) on the Manitoba (MB) farm. The findings, while approximate, illustrate the importance of considering all GHGs simultaneously, and show that practices which best reduce emissions may vary among locations. The findings also suggest merit in comparing emissions on the basis of CO2e per unit of protein exported off-farm, rather than on the basis of total CO2e or CO2e per hectare.

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Informing urban climate planning with high resolution data: the Hestia fossil fuel CO2 emissions for Baltimore, Maryland

Carbon Balance and Management ◽

10.1186/s13021-020-00157-0 ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Geoffrey S. Roest ◽

K. R. Gurney ◽

S. M. Miller ◽

J. Liang

Keyword(s):

Greenhouse Gas ◽

Fossil Fuel ◽

Ghg Emissions ◽

Point Sources ◽

The Self ◽

Greenhouse Gas Mitigation ◽

Electricity Production ◽

Ghg Mitigation ◽

High Resolution Data ◽

Atmospheric Monitoring

Abstract Background Cities contribute more than 70% of global anthropogenic carbon dioxide (CO2) emissions and are leading the effort to reduce greenhouse gas (GHG) emissions through sustainable planning and development. However, urban greenhouse gas mitigation often relies on self-reported emissions estimates that may be incomplete and unverifiable via atmospheric monitoring of GHGs. We present the Hestia Scope 1 fossil fuel CO2 (FFCO2) emissions for the city of Baltimore, Maryland—a gridded annual and hourly emissions data product for 2010 through 2015 (Hestia-Baltimore v1.6). We also compare the Hestia-Baltimore emissions to overlapping Scope 1 FFCO2 emissions in Baltimore’s self-reported inventory for 2014. Results The Hestia-Baltimore emissions in 2014 totaled 1487.3 kt C (95% confidence interval of 1158.9–1944.9 kt C), with the largest emissions coming from onroad (34.2% of total city emissions), commercial (19.9%), residential (19.0%), and industrial (11.8%) sectors. Scope 1 electricity production and marine shipping were each generally less than 10% of the city’s total emissions. Baltimore’s self-reported Scope 1 FFCO2 emissions included onroad, natural gas consumption in buildings, and some electricity generating facilities within city limits. The self-reported Scope 1 FFCO2 total of 1182.6 kt C was similar to the sum of matching emission sectors and fuels in Hestia-Baltimore v1.6. However, 20.5% of Hestia-Baltimore’s emissions were in sectors and fuels that were not included in the self-reported inventory. Petroleum use in buildings were omitted and all Scope 1 emissions from industrial point sources, marine shipping, nonroad vehicles, rail, and aircraft were categorically excluded. Conclusions The omission of petroleum combustion in buildings and categorical exclusions of several sectors resulted in an underestimate of total Scope 1 FFCO2 emissions in Baltimore’s self-reported inventory. Accurate Scope 1 FFCO2 emissions, along with Scope 2 and 3 emissions, are needed to inform effective urban policymaking for system-wide GHG mitigation. We emphasize the need for comprehensive Scope 1 emissions estimates for emissions verification and measuring progress towards Scope 1 GHG mitigation goals using atmospheric monitoring.

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Greenhouse gas emissions from tropical coastal wetlands and their alternative agricultural lands: Where significant mitigation gains lie

10.5194/bg-2021-28 ◽

2021 ◽

Author(s):

Naima Iram ◽

Emad Kavehei ◽

Damien T. Maher ◽

Stuart E. Bunn ◽

Mehran Rezaei Rashti ◽

...

Keyword(s):

Land Use ◽

Greenhouse Gas ◽

Financial Incentives ◽

Coastal Wetlands ◽

Agricultural Land ◽

Ghg Emissions ◽

N2o Emissions ◽

Co2 Fluxes ◽

Agricultural Lands ◽

Ghg Mitigation

Abstract. Tidal coastal wetlands are significant to the global carbon budgets through carbon sequestration and greenhouse gas (GHG; CO2, CH4 and N2O) emissions. The conversion of tidal coastal wetlands to agriculture land alters soil processes changing GHG emissions. The GHG emissions associated with land-use change are important for restoration strategies that rely upon financial incentives such as carbon credits. We measured GHG fluxes from mangroves, saltmarsh and freshwater tidal forest and their alternative agricultural lands including sugarcane and ponded pastures. We investigated seasonal variations between June 2018 and February 2020 in tropical. Australia. The wet ponded pasture had by far the highest CH4 emissions with 1,231 ± 386 mg m−2 d−1, which were 200-fold higher than any other land use. Agricultural lands were the most significant sources of N2O emissions with 55 ± 9 mg m−2 d−1 from dry ponded pasture (wet-hot period) and 11 ± 3 mg m−2 d−1 from sugar cane (hot-dry period), coinciding with fertilisation. The N2O fluxes from the tidal coastal wetlands ranged between −0.55 ± 0.23 and 2.76 ± 0.45 mg m−2 d−1 throughout the study period. The highest CO2 fluxes of 20 ± 1 g m−2 d−1 were from the dry ponded pasture during the wet-hot period, while the saltmarsh had the lowest CO2 fluxes having an uptake of −1.19 ± 0.08 g m−2 d−1 in the dry-hot period. Overall, agricultural lands had significantly higher total cumulative GHG emissions (CH4 + N2O) of 7142 to 56,124 CO2-eq kg ha−1 y−1 compared to those of any type of tidal coastal wetlands, which ranged between 144 and 884 CO2-eq kg ha−1 y−1. Converting agricultural land, particularly wet ponded pasture, to tidal coastal wetlands could provide large GHG mitigation gains and potential financial incentives.

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Find Opportunities Within USDA Programs to Reduce GHG Emissions and Increase Carbon Sequestration

10.32747/2016.6960274.ch ◽

2016 ◽

Author(s):

Chris Swanston ◽

Kristen Schmitt ◽

Danielle Shannon ◽

Jad Daley

Keyword(s):

Carbon Sequestration ◽

Greenhouse Gas ◽

Working Group ◽

Ghg Emissions ◽

Forest Carbon ◽

Greenhouse Gas Mitigation ◽

Forest Sector ◽

Ghg Mitigation ◽

Workshop Summary ◽

Northern Forests

The USDA Northern Forests Climate Hub (NFCH) and the Forest-Climate Working Group (FCWG) held a series of two workshops designed to identify specific opportunities within USDA programs to explicitly support greenhouse gas mitigation in the forest sector. The first workshop (Perspectives from the Field) gathered suggestions and ideas from field practitioners familiar with using USDA programs to support forest carbon benefits. The second workshop (Finding USDA Programmatic GHG Mitigation Opportunities) invited USDA Program leads and representatives to develop specific suggestions on modifications to USDA Programs that could assist in these efforts. The final outcome was a series of twelve ideas from USDA Program leads and representatives that took into account input from the field, and outlined specific needs for each idea. These twelve are listed below and summarized more completely in the Workshop summary section description.

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Potential Greenhouse Gas Mitigation through Temperate Tree-Based Intercropping Systems

The Open Agriculture Journal ◽

10.2174/1874331501004010049 ◽

2010 ◽

Vol 4 (1) ◽

pp. 49-57 ◽

Cited By ~ 14

Author(s):

Andrew K. Evers ◽

Amanda Bambrick ◽

Simon Lacombe ◽

Michael C. Dougherty ◽

Matthias Peichl ◽

...

Keyword(s):

Climate Change ◽

Greenhouse Gas ◽

Global Climate ◽

Ghg Emissions ◽

Greenhouse Gas Mitigation ◽

Research Station ◽

Agricultural Field ◽

Agricultural Producers ◽

Ghg Mitigation ◽

Sequestration Potential

Increasing awareness of global climate change has pressured agricultural producers to reduce greenhouse gas (GHG) emissions while at the same time encouraging them to maintain food production needed for an increasing population. Tree-based intercropping (TBI) systems are believed to be useful in climate change mitigation, especially in temperate regions, due to their potential to reduce GHG emissions from agricultural practices. The purpose of this paper is therefore to review some of the research conducted on GHG mitigation in TBI in southern Ontario and Quebec, Canada. Research conducted at the University of Guelph Agroforestry Research Station (GARS) indicated that TBI systems had the potential to lower N2O emissions by 1.2 kg ha-1 y-1 compared to a conventional agricultural field cropping system. Trees can assimilate residual nitrate (NO3-) left from nitrogen (N) fertilizer applications, thereby leaving less NO3- available for denitrification and subsequently reducing N2O losses. Carbon sequestration is also enhanced in TBI systems as carbon (C) is stored in both above and below ground tree components. Soil Organic Carbon (SOC) is higher in systems incorporating trees because tree litter decomposes slowly, therefore reducing CO2 loss to the atmosphere. The C sequestration potential of TBI systems and the possibility to include fast-growing tree species for bioenergy production in TBI systems make it a valid solution to mitigate climate change in temperate regions. The opportunity of C trading credits to offset the costs of implementing a TBI system and provide additional income to farmers could facilitate the adoption of TBI amidst agricultural producers in temperate regions.

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