Integrated assessment of climate change impacts on crop productivity and income of commercial maize farms in northeast South Africa


Agriculture in South Africa sustains about 70% of the region’s population for food, income and employment, playing an important role for food security and the local economy. The focus of the study was the commercial maize farms of the Free State Province given their importance in the National economy. The Regional Integrated Assessment (phase I) was implemented to assess climate change and adaptation that links climate, crops, economic data and tools developed by the Agricultural Model Intercomparison and Improvement Project (AgMIP). In this context, the “system” is defined as a whole of agronomic and socio-economic factors. Within that framework three core questions were being evaluated: (i) Impacts of climate change under current system; (ii) Impacts of climate change under future system; (iii) The role of adaptation under climate change and the future system. Maize production will decrease between 10% to 16% as a result of projected climate impacts. Also, current agricultural production systems are negatively affected by climate change with an increase in poverty rates between 2% to 3%. The projected adoption of the adapted technology would result in positive increased net returns and a decrease in poverty rate of between 12% and 22%. The results of this study show that implementing adaptation measures, including strategies indicated by the local stakeholders, will have positive impacts on the agricultural production systems and can contribute to support and inform climate change policy decision making such as the development of National Adaptation Plans.

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Research reported in this article was possible owing to generous financial support from the UK Department for International Development, project GB-1-202108 to AgMIP, the Agricultural Model Intercomparison and Improvement Project. Fund disbursement on behalf of AgMIP was facilitated by USDA-ARS, Columbia University, and ICRISAT. Results reported reflect the views of the authors. We also thank the two anonymous reviewers and the Editor for the feedback that helped to improve the manuscript. Funding support was provided by the NASA Earth Sciences Division for the GISS Climate Impacts Group (281945.

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Correspondence to Davide Cammarano.

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Agricultural Research Council-Roodeplaat is a former affiliation of Y. G. Beletse

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Cammarano, D., Valdivia, R.O., Beletse, Y.G. et al. Integrated assessment of climate change impacts on crop productivity and income of commercial maize farms in northeast South Africa. Food Sec. 12, 659–678 (2020).

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  • Integrated assessment
  • Climate change
  • Crop modelling
  • Adaptation
  • Climate models
  • Economic modelling