Research Collaborators

• Chris Barrett (Professor, Applied Economics and Management)
• Larry Blume (Professor, Economics)
• Doug Brown (PhD, Applied Economics and Management, conferred 2004)
• Heidi Hogset (PhD, Applied Economics and Management, conferred 2005)
• Jane Kapkiyai (PhD candidate, Crop and Soil Sciences)
• Joseph Kimetu (PhD candidate, Crop and Soil Sciences)
• James Kinyangi (PhD, Crop and Soil Sciences, conferred 2007)
• Johannes Lehmann (Associate Professor, Crop and Soil Sciences)
• Paswel Marenya (PhD candidate, Natural Resources)
• Helen Markewich (PhD candidate, Animal Science)
  
• David Mbugua (Post-doctoral Associate, Cornell University/World Agroforestry Centre/Kenya Agricultural Research Institute)
• Festus Murithi (Economist, Kenya Agricultural Research Institute)
• Solomon Ngoze (PhD candidate, Earth and Atmospheric Sciences)
• Florence Nherera (PhD, Animal Science, conferred 2006)
• Chuck Nicholson (Research Associate, Applied Economics and Management)
• James Ouma (Economist, Kenya Agricultural Research Institute)
• David Parsons (Graduate Student, Crop and Soil Science)
• Alice Pell (Professor, Animal Science)
• Max Pfeffer (Professor, Development Sociology)
• Frank Place (Economist, World Agroforestry Centre)
• John Recha (PhD candidate, Crop and Soil Sciences)
• Susan Riha (Professor, Earth and Atmospheric Sciences)
• Keenan Roberts (Graduate Student, Animal Science)
• Keith Shepherd (Soil Scientist, World Agroforestry Centre)
• Dawit Solomon (Research Associate, Crop and Soil Sciences)
• Emma Stephens (PhD candidate, Economics)
• Lou Verchot (Ecologist, World Agroforestry Centre)
• Justin Wangila (Associate Economist, World Agroforestry Centre)

Outputs by Author

David M. Amudavi (PhD conferred 2005, Education)

• Amudavi, D., M. Kroma and K. Davis. 2006. Understanding effects of institutional partnerships on rural groups in improving livelihoods in Kenya. Paper presented at the Association for International Agricultural and Extension Education’s 22nd Conference, ‘International Teamwork in Agricultural and Extension Education’, 14-19 May 2006, Clearwater Beach, Florida.
• Amudavi, D. 2006. The effects of farmer community group participation on rural livelihoods in Kenya.
• Amudavi, D. 2005. The contributions of farmer group participation to improved natural resource management cases. Policy Brief No. 7.
• Amudavi, D. 2004. Social aspects of dynamic poverty traps: cases from Vihiga, Baringo and Marsabit Districts, Kenya. Paper presented at KIPPRA-Cornell SAGA workshop on Qualitative and Quantitative Methods for Poverty Analysis. March 2004. Nairobi, Kenya.

Christopher Barrett (Professor, Applied Economics and Management)

• Barrett, C.B. Poverty Traps and Resource Dynamics In Smallholder Agrarian Systems, in Arjan Ruis and Rob Dellink, editors, Economics of poverty, the environment and natural resource use (Berlin: Springer, forthcoming).
• Barrett, C.B., P.P. Marenya, J. McPeak, B. Minten, F. Murithi, W. Oluoch-Kosura, F. Place, F., Randrianarisoa, J.C., Rasambainarivo, J., Wangila.  2006. Welfare dynamics in rural Kenya and Madagascar. Journal of Development Studies 42 (1), 248-277. DOI: 10.1080/00220380500405394
• Barrett, C.B. 2005. Poverty traps and agricultural research: improving policies, institutions and technologies to support sustainable poverty reduction. Paper presented at the Consultative Group on International Agricultural Research Forum. CGIAR Priorities: Science for the Poor, 6 December 2005, Marrakech, Morocco.
• Barrett, C.B. 2005. "Mixing Qualitative and Quantitative Methods in Analyzing Poverty Dynamics", in Walter Odhiambo, John M. Omiti and David I. Muthaka, editors, Quantitative and Qualitative Methods for Poverty Analysis (Nairobi: Kenya Institute for Public Policy Research and Analysis).

Doug Brown (PhD conferred 2004, Applied Economics and Management)

• Brown, D.R., E.C. Stephens, J.O. Ouma, F.M. Murithi & C.B. Barrett. 2006. Livelihood strategies in the rural Kenyan Highlands. African Journal of Agricultural and Resource Economics, 1(1): 21-36.
• Brown, D.R. & C.B. Barrett. 2005. Maize-bean intercropping and smallholder productivity in the Kenya’s Highlands. Policy Brief No.8.
• Brown, D.R. & C.B. Barrett. 2005. Lessons For Rural Development Practitioners from Recent Agricultural Development Economics Research, in Judith Dean, Julie Schaffner and Stephen Smith, editors, Poverty Reduction In The Developing World.  (World Vision, 2005). 
• Brown, D.R. & S. Tsoi. 2005. Kenya Highland Smallholder Agriculture: NSF Bioeconomic Model Documentation Version 1-0, Cornell University, Ithaca, NY.

Heidi Hogset (PhD conferred 2005, Applied Economics and Management)

• Hogset, H. On Economic Transfers Through Social Networks in Kenya’s Smallholder Sector, in C.B. Barrett, A.G. Mude and J.M. Omiti, Editors, Decentralization and the Social Economics of Development (CABI, forthcoming).
• Heidi Hogset and Christopher B. Barrett. Imperfect Social Learning Among Kenyan Smallholders," April 2007 draft.
• Hogset, H. 2005. Social Networks and Technology Adoption. Policy Brief No. 6
• Hogset, H. 2002. Traditional Insurance and Adoption of a Lumpy New Technology with Delayed and  Uncertain Benefits

Joseph Kimetu (PhD candidate, Crop and Soil Science)

• Kimetu, J.,  J. Lehmann, A. Pell and J. Thies. 2007. Carbon sequestration and mitigation of carbon accumulation in the biosphere: the role of biochar in tropical agricultural systems. 2007 International AgriChar Initiative Conference. Terrigal, New South Wales, Australia. April 29-May 2, 2007.
  

James Kinyangi (PhD conferred 2007, Crop and Soil Science)

• Kinyangi, J., D. Solomon, B. Liang, M. Lerotic, S. Wirick and J. Lehmann. 2006. Nanoscale biogeocomplexity of the organo-mineral assemblage in soil: application of STXM microscopy and C 1s-NEXAFS spectroscopy. Soil Science Society of America Journal 70: 1708-1718.
• Kinyangi, J., J. Lehmann, B. Liang and D. Solomon. 2006. Microscale Synchrotron-FTIR Mapping of Carbon “Hot Spots” on Mineral Surfaces in Soil. 18th world Congress of Soil Science, July 9-15, Philadelphia, Pennsylvania, USA.
• Kinyangi, J., J. Lehmann, A. Pell, J. Thies, S. Ngoze, S. Riha, D.M. Mbugua and L. Verchot. 2006. Soil Organic Matter Stabilization and Associated Degradation Threshold Dynamics. 18th world Congress of Soil Science, July 9-15, Philadelphia, Pennsylvania, USA.
• Kinyangi, J. Lehmann, B. Liang, D. Solomon, and S. Ngoze. 2005.  Organic Matter Stabilization in Biogenic Nanostructures of Soil Micro-Aggregates. Annual Meeting, American Society of Agronomy, Salt Lake City, UT, November 6-10, 2005
• Kinyangi JM, J. Lehmann and DM Solomon. 2004. Using carbon K-edge XANES to assess organic matter stabilization in microaggregates during 100 years of cropping. Annual Meeting, American Society of Agronomy, Seattle, WA, November 1-4, 2004. CD ROM. Program p. 395.
• Kinyangi, J.M., J. Lehmann, J. Thies, A.N. Pell, L. Verchot, C.B. Barrett, S. Ngoze, D. Mbugua and S. Riha. 2004. Biogeochemical characteristics of organic matter fractions that confer thresholds during soil degradation. Annual Meeting, American Society of Agronomy, Seattle, WA, November 1-4, 2004 . CD ROM. Program p. 396.

Johannes Lehmann (Associate Professor, Crop and Soil Science )

• Lehmann J, J. Kinyangi and D. Solomon. 2007. Organic matter stabilization in soil microaggregates: implications from spatial heterogeneity of organic carbon contents and carbon forms. Biogeochemistry, in press.
• Lehmann, J., J. Kinyangi and D. Solomon. 2006. In-situ assessment of the spatial association of organic carbon and clay mineral forms in soil. ASA-CSA-SSSA International Annual Meeting. November 12-16, 2006.

Paswel Marenya (PhD candidate, Natural Resources)

• Marenya, P.M. & C.B. Barrett. 2007. Household-level determinants of adoption of improved natural resources management practices among smallholder farmers in western Kenya. Food Policy 32(4): 515-536.
• Marenya, P.P. & C.B. Barrett, "State-conditional fertilizer yield response: Towards an explanation of soil degradation poverty traps." February 2007.
• Marenya, P.P. & C.B. Barrett. 2005. Adoption of Integrated Natural Resources Management Practices among Smallholder Farmers in Western Kenya.  A BASIS CRSP Policy Brief No. 5.

Florence Nherera (PhD conferred 2006)

• Nherera, F.V., A.N. Pell, D.G. Fox, L.O. Tedeschi, D.M. Mbugua, I.W. Kariuki, J.N Kangara. Predicting energy and protein supply and milk production of crossbred cows consuming high forage rations in the central highlands of Kenya. (Submitted for Publication).

Solomon Ngoze (PhD candidate)

• Ngoze, S. S. Riha, J. Kinyangi, J. Lehmann, L. Verchot, D. Mbugua and A.N. Pell. 2006. Soil Fertility Degradation and Management in the Highlands of Kenya. 18th world Congress of Soil Science, July 9-15, Philadelphia, Pennsylvania, USA.
• Ngoze, S., S. Riha, C. Barrett and A. Pell. 2005. Soil fertility in smallholder farms of the highlands of Kenya: Impacts of site, land use and household resources. Annual Meeting, American Society of Agronomy, Salt Lake City, UT, November 6-10, 2005.
• Ngoze S., S. Riha, L. Verchot, A. Pell, J. Kinyangi, D. Mbugua and J. Lehmann. 2004. Nitrogen fluxes in soils amended with animal manure and tithonia biomass on a soil degradation chronosequence. Annual Meeting, American Society of Agronomy, Seattle , WA, November 1-4, 2004 . CD ROM. Program p. 239.

Alice Pell (Professor, Animal Science; Director, CIIFAD)

• Pell, A.N., J.M. Kinyangi, S.O. Ngoze, D.R. Brown, D.M. Mbugua, C.B. Barrett, L.E. Blume, J.G. Gamara, C.J. Lehmann, P.P. Marenya, H.A. Markewich, A.O. Odenyo, S.J. Riha, L.V. Verchot, and J. Wangila. 2005. Dynamics of poverty and soil degradation on smallholder farms in central and western Kenya. Workshop for Enhancing Collaborative Research on the Environment in Sub-Saharan Africa, National Science Foundation on Sub-Saharan Africa, Arlington, VA. January 24-6, 2005.
• Pell, A.N., D.M. Mbugua, L.V. Verchot, C.B. Barrett, L.E. Blume, J.G.P. Gamarra, J.M. Kinyangi, C.J. Lehmann, A.O. Odenyo, S.O. Ngoze, B.N. Okumu, M.J. Pfeffer, P.P. Marenya, S.J. Riha, and J. Wangila. 2004. The Interplay Between Smallholder Farmers and Fragile Tropical Agroecosystems in Kenya. Symposium on Frontiers in Biocomplexity: Reciprocal Interactions between Human and Natural Systems. AAAS Annual Meeting, February 14, 2004, Seattle, WA.

Dawit Solomon (Research Associate, Crop and Soil Science)

• Solomon , D., J. Lehmann,  J. Kinyangi, W. Amelung, I. Lobe, S. Ngoze,  S. Riha, A. Pell, L. Verchot, D. Mbugua, J. Skjemstad & T. Schafer. 2007. Long-term impacts of anthropogenic perturbations on the dynamics and molecular speciation of organic carbon in tropical forest and subtropical grassland ecosystems. Global Change Biology 13: 511-530.
• Solomon, D., J. Lehmann, J. Kinyangi, B. Liang, I. Lobe, W. Amelung and T. Schaefer. 2006.  Soil organic C speciation and transformation following long-term anthropogenic perturbations in tropical ecosystems: evidence from 13C NMR and synchrotron-based C (1s) NEXAFS and FTIR-ATR spectroscopy. In World Congress of Soil Science, 9-14 July 2006, Philadelphia. Abstract 18543, poster 134-2.
• Solomon, D., J. Lehmann, J. Kinyangi, B. Liang, I. Lobe, W. Amelung and T. Schaefer. 2005. Organic carbon in tropical ecosystems: insights into the chemical speciation and transformation using C-NEXAFS, SR-FTIR-ATR and 13C NMR spectroscopy. The 2nd International Conference on Mechanisms of Organic Matter Stabilization and Destabilization in Soils. Asilomar, CA. p. 99.

Emma Stephens (PhD candidate, Dept. of Economics)

• Stephens, E. C. and C. Barrett. 2006. Incomplete Credit Markets and Commodity Marketing Behavior. (draft). 44.p.

Workshops/Conferences

• Interdisciplinary Science for Integration of Socioeconomic and Biophysical Processes in East Africa
  Dar es Salaam, Tanzania (May 8-11, 2006)
• Crops, Livestock, and Soils in Smallholder Economic Systems (CLASSES) Simulation Model Training Workshop
  ICRAF, Narirobi, Kenya (Jan. 15-19, 2007)
  - download overview PowerPoint
• Cognitive Mapping Introductory Farmers Focused Group Discussions
  Madzuu, Kenya (Jan. 29, 2004)
• Soil nutrient dynamics, crop productivity and household welfare dynamics: Research findings
  4 sites in W. Kenya (Jan. 2-5, 2007)

* Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.