Food Security

, Volume 4, Issue 3, pp 423–439 | Cite as

“Modeling the impact of natural resource-based poverty traps on food security in Kenya: The Crops, Livestock and Soils in Smallholder Economic Systems (CLASSES) model”

  • Emma C. Stephens
  • Charles F. Nicholson
  • Douglas R. Brown
  • David Parsons
  • Christopher B. Barrett
  • Johannes Lehmann
  • David Mbugua
  • Solomon Ngoze
  • Alice N. Pell
  • Susan J. Riha
Original Paper


We investigate the interactions between natural resource-based poverty traps and food security for smallholder farms in highland Kenya using a recently developed system dynamics bio-economic model. This approach permits examination of the complex interactions and feedback between farm household economic decision-making and long-term soil fertility dynamics that characterize persistent poverty and food insecurity among smallholders in rural highland Kenya. We examine the effects of changing initial endowments of land and stocks of soil organic matter on smallholders’ well being, as reflected in several different indicators. We show that larger and higher quality land endowments permit accumulation of cash and livestock resources and conservation of soil organic matter relative to smaller or more degraded farms. This suggests the existence of asset thresholds that divide food secure households from food insecure ones.


Poverty traps Kenya Food security Bio-economic modeling System dynamics 


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Copyright information

© Springer Science + Business Media B.V. & International Society for Plant Pathology 2012

Authors and Affiliations

  • Emma C. Stephens
    • 1
  • Charles F. Nicholson
    • 2
  • Douglas R. Brown
    • 3
  • David Parsons
    • 4
  • Christopher B. Barrett
    • 5
  • Johannes Lehmann
    • 6
  • David Mbugua
    • 7
  • Solomon Ngoze
    • 8
  • Alice N. Pell
    • 9
  • Susan J. Riha
    • 8
  1. 1.Pitzer CollegeClaremontUSA
  2. 2.Cal Poly San Luis Obispo, Dept. of AgribusinessSan Luis ObispoUSA
  3. 3.World Vision InternationalMississaugaCanada
  4. 4.University of Tasmania, Agricultural ScienceHobartAustralia
  5. 5.Cornell University, Applied Economics and ManagementIthacaUSA
  6. 6.Cornell University, Crop and Soil SciencesIthacaUSA
  7. 7.World Agroforestry Centre (ICRAF)NairobiKenya
  8. 8.Cornell University, Earth and Atmospheric ScienceIthacaUSA
  9. 9.Cornell University, Animal ScienceIthacaUSA

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