Improving estimation of nitrous oxide emissions from agriculture
Mitigating climate change requires accurate and spatially explicit estimates of greenhouse gas emissions that take into account variable soil, climate and management conditions. Research has revealed that the current methods used to estimate nitrous oxide emissions from nitrogen fertilizer usage may underestimate actual emissions by up to five-fold and fail to identify hotspots. In addition, no scalable model exists that can estimate nitrous oxide emissions, and the data needed to develop suitable models for GHG emissions in tropical and subtropical wheat- and maize-based cropping systems are lacking. Thus, mitigation policies and priorities are based on poor data and estimates of the impacts of nitrogen fertilizer on nitrous oxide emissions.
With the increase in national reporting associated with the Paris Agreement, demand for better emissions data and evidence-based mitigation options is increasing. This project met these demands by investigating the following questions:
- How can models better quantify smallholder greenhouse gas (GHG) emissions and mitigation options associated with nitrogen, especially agricultural fertilizers?
- How do data requirements, scale, and end-user objectives influence model selection to provide appropriate policy analysis and decision support tools for assessing mitigation priorities?
- What are the critical trade-offs and synergies between GHG mitigation practices and other smallholder objectives, including reduced poverty, nutrition, and gender equity?
At the local level, the project worked with extension actors to focus on demonstrating the economic benefits resulting from more efficient nitrogen use. And at national and regional levels, the project analyzed nitrogen fertilizer subsidies and related policies.
The project met demands for information from stakeholders and decision-makers at all levels, including the Global Alliance for Climate Smart Agriculture (GACSA), the Intergovernmental Panel on Climate Change (IPCC), public and private sector institutions involved with the provision and distribution of nitrogen fertilizers and subsidies, and both governmental and non-governmental agricultural extension.
Outputs from this research are used to refine climate-smart practices that aim to increase productivity for smallholders (women and men), while minimizing negative environmental outcomes, including emissions. Decision-makers will use improved data and methods to support policies that reduce greenhouse emissions and influence policies on nitrogen fertilizer subsidies at international and national levels. Project partners, including local governments, non-governmental organizations, the private sector and other bilateral projects, are then empowered to scale up evidence-based mitigation practices that also contribute to food security, with a particular focus on efficient nitrogen management and soil management recommendations.
The project also aimed to contribute massively to mitigation plans globally by informing the IPCC with more accurate recommendations for nitrogen management in wheat- and maize-based systems and adjusting targets for nitrogen management.
Improving the estimation of nitrous oxide emissions from agriculture aims to reduce nitrous oxide emissions by 20% from cereal-based systems in India and Mexico.
Research activities and results from this project are informing the "Cost-effective cropland mitigation" project beginning in 2019.
- Albanito, F., Lebender, U., Cornulier, T., Sapkota, T., Brentrup, F., Stirling, C., and Hillier, J. (2017). Direct nitrous oxide emissions from tropical and sub-tropical agricultural systems - a review and modelling of emissions factors. Scientific Report 7.
- Farnworth CR, Stirling C, Sapkota TB, Jat ML, Misiko M, Attwood S. 2017. Gender and inorganic nitrogen: what are the implications of moving towards a more balanced use of nitrogen fertilizer in the tropics? International Journal of Agricultural Sustainability 15(2):136-152.
- Richards M, van Ittersum M, Mamo T, Stirling C, Vanlauwe B, Zougmoré R. 2016. Fertilizers and low emission development in sub-Saharan Africa. CCAFS Policy Brief no. 11.
- Related: Basak R. 2016. Benefits and costs of nitrogen fertilizer management for climate change mitigation: Focus on India and Mexico. CCAFS Working Paper no. 161.
Expected outputs include:
- Robust evidence-base support of climate-smartness of nitrogen management practices at field level.
- Analysis of landscape-level nitrous oxide emission mitigation strategies in maize- and wheat-based cropping systems.
- Open access database of nitrous oxide emissions from agricultural soils including published and unpublished sources where possible.
- New empirical model(s) for nitrous oxide emissions.
- Technical specification for inclusion of the new nitrous oxide model in the Cool Farm Tool and the CCAFS–Mitigation Options Tool (CCAFS-MOT).
The International Maize and Wheat Improvement Center (CIMMYT) led this project, in a technical collaboration with the University of Aberdeen. CIMMYT targets research outputs to Fertilizers Europe, the International Fertilizer Association, the Sustainable Agriculture Initiative, the IPCC, the Global Research Alliance on Agricultural Greenhouse Gases, FAOSTAT and private fertilizer companies (such as Yara) to support the identification of optimal regional fertilizer application strategies and extension activities. At the local level, we work with extension actors to focus on demonstrating the economic benefits of more efficient nitrogen use.
For further information, please contact Project Leader, Clare Stirling (CIMMYT) email@example.com.