TOA-MD5.0: A Novel Approach to Multi-Dimensional Impact Assessment

The TOA project’s goals are to disseminate and further develop the TOA method and modeling tools to support informed research investment and policy decision making. This is accomplished through collaborative research and capacity building with researchers and related organizations.

title page of TOA-MD 5.0  

TOA-MD worldwide

Click on the map to view where the TOA Model is in use globally

  • The TOA Project develops modeling tools that can be used by research teams to improve the understanding of agricultural system sustainability and inform policy decisions. 
  • The TOA Project also provides training to empower researchers and institutions to use these modeling tools.
  • For more information on the Tradeoffs approach, check out these key publications and the TOA project history.
  • Click on the TOA-MD image at right for an introduction to what TOA-MD5.0 can do!

Featured Publications

AGMIP Bood Cover

Antle, J. M., R.O. Valdivia, K.J. Boote, S. Janssen, J.W. Jones, C.H. Porter, C. Rosenzweig, A.C. Ruane, and P.J. Thorburn. (2015). AgMIP’s Trans-disciplinary Agricultural Systems Approach to Regional Integrated Assessment of Climate Impact, Vulnerability and Adaptation. In  Handbook of Climate Change and Agroecosystems: The Agricultural Model Intercomparison and Improvement Project (AgMIP) Integrated Crop and Economic Assessments. C. Rosenzweig and D. Hillel, eds. ICP Series on Climate Change Impacts, Adaptation, and Mitigation: Volume 3 Part 1. London: Imperial College Press, 27-44. doi: 10.1142/9781783265640_0002.

PDFs of this chapter and the full handbook available online at You may request a copy of this chapter for personal use by emailing us at 

Valdivia, R.O., J.M. Antle, C. Rosenzweig, A.C. Ruane, J. Vervoot, M. Ashfaq, I. Hathie, S.H.-K. Tui, R. Mulwa, C. Nhemachena, P. Ponnusamy, H. Rasnayaka, and H. Singh, 2015: Representative agricultural pathways and scenarios for regional integrated assessment of climate change impacts, vulnerability, and adaptation. In Handbook of Climate Change and Agroecosystems: The Agricultural Model Intercomparison and Improvement Project (AgMIP) Integrated Crop and Economic Assessments. C. Rosenzweig, and D. Hillel, Eds., ICP Series on Climate Change Impacts, Adaptation, and Mitigation Vol. 3. Londoin: Imperial College Press, 101-156, doi:10.1142/9781783265640_0005.

PDFs of this Chapter and the full handbook are available online at  You may request a copy of this chapter for personal use by emailing us at  


Image of Agricultural Systems journal

Economic trade-offs of biomass use in crop-livestock systems: Exploring more sustainable options in semi-arid Zimbabwe by Sabine Homann-Kee Tui, Diego Valbuena, Patricia Masikati, Katrien Descheemaeker, Justice Nyamangara, Lieven Claessens, Olaf Erenstein, Andre van Rooyen, Daniel Nkomboni.  Agricultural Systems 2014. Available online.

Abstract: In complex mixed crop-livestock systems with limited resources and biomass scarcity, crop residues play an important but increasingly contested role. This paper focuses on farming systems in the semi-arid areas of Zimbabwe, where biomass production is limited and farmers integrate crop and livestock activities. Conservation Agriculture (CA) is promoted to intensify crop production, emphasizing the retention of surface mulch with crop residues (CR). This paper quantifies the associated potential economic trade-offs and profitability of using residues for soil amendment or as livestock feed, and explores alternative biomass production options. We draw on household surveys, stakeholder feedback, crop, livestock and economic modeling tools. We use the Trade-Off Analysis Model for Multi Dimensional Impact Assessment (TOA-MD) to compare different CR use scenarios at community level and for different farm types: particularly the current base system (cattle grazing of maize residues) and sustainable intensification alternatives based on a CA option (mulching using maize residues ± inorganic fertilizer) and a maize–mucuna (Mucuna pruriens) rotation. Our results indicate that a maize–mucuna rotation can reduce trade-offs between CR uses for feed and mulch, providing locally available organic soil enhancement, supplementary feed and a potential source of income. Conservation Agriculture without fertilizer application and at non-subsidized fertilizer prices is not financially viable; whereas with subsidized fertilizer it can benefit half the farm population. The poverty effects of all considered alternative biomass options are however limited; they do not raise income sufficiently to lift farmers out of poverty. Further research is needed to establish the competitiveness of alternative biomass enhancing technologies and the socio-economic processes that can facilitate sustainable intensification of mixed crop-livestock systems, particularly in semi-arid environments.



Upcoming Events

  • 4th Annual Global TOA-MD Workshop...  Stay tuned for more details on date and location.

Previous workshops and presentations

  • The 3rd Annual Global TOA-MD Workshop held June 9-13 2014 at the ILRI Campus in Addis Ababa was a great success! The course, focusing on Crop-Livestock Modeling, was attended by 20 CGIAR Scientists. This course was organized in collaboration with Mario Herrero (CSIRO) to utilize the livestock model Ruminant with TOA-MD.
  • The 2nd Annual Global TOA-MD Workshop was held June 17-21 2013 at OSU in Corvallis.
  • John Antle and Roberto Valdivia led and organized the AgMIP TOA-MD Economic Modeling Workshop in Dubai, UAE, April 29 -May 3, 2013. See more information at
  • Download the poster: TOA-MD: An Novel Simulation Approach to Multi-Dimensional Impact Assessment
  • Download the poster: TOA-MD: A New Approach to Assess Climate Change Impacts
  • John Antle and Roberto Valdivia attended the AgMIP Sub-Saharan Africa Regional Workshop in Accra, Ghana, September 10-14, 2012, and the AgMIP South Asia Regional Workshop in Colombo, Sri Lanka, November 12-16, 2012. See information about these workshops at
  • John Antle, Roberto Valdivia and Jianhong Mu attended the first AgMIP North America meeting in Ames, IA, September 5-7, 2012. A group of economists met at this meeting to discuss possible model inter-comparison and impact assessment activities for the North American region. A summary of the Economics Breakout Sessions is available. Economists from the region are invited to express interest in participation in AgMIP North America. 
  • The 1st Annual Global TOA-MD Workshop was held June 19-23 at OSU in Corvallis.
  • John Antle received the Agricultural & Applied Economics Association’s prestigious Quality of Research Discovery Award for the paper “Parsimonious Multi-Dimensional Impact Assessment” published in the 2011 AJAE. The award was presented to John at the AAEA Awards & Fellows Recognition Ceremony at the 2012 AAEA Annual Meeting to be held in Seattle from August 12–14, 2012.
  • New Methods to Assess Climate Change Impacts and Adaptation for Poor Agricultural Households by John M. Antle, Roberto Valdivia. Seminar presented at the UK Department for International Development, London, May 10 2012.
  • Moving Along the Impact Pathway: The Case of IAA in Bangladesh by John Antle & Roberto Valdivia Oregon State University and Charles Crissman & Khondker Murshed-e-Jahan WorldFish Center. Presented at Assessing the impacts of international agricultural research on poverty and under-nutrition: A mid-term workshop for studies commissioned by the CGIAR Standing Panel on Impact Assessment (2011 – 2013),London International Development Centre, May 8-9 2012.