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Regression tree analysis of soil fertility and agro-economic practices and the effects on yield in Tanzania

Author

Listed:
  • Jan Lietava
  • Risa Morimoto

    () (Department of Economics, SOAS University of London, UK)

Abstract

Food security and yield production have been extensively studied in regard to fertiliser response in the context of Sub-Saharan Africa. Soil fertility gradients within farms interact with other complex factors such as plot management, alongside bio-physical as well as socio-economic constraints, to create extensive heterogeneity in yield production. Hence, blanket recommendations regarding increasing inputs may not just lead to limited or no change in productivity but may affect long term sustainability. To try and explore the relationships between these factors, Classification and Regression Tree (CART) analysis was used to simplify the effect of plot management decisions. Data was from the focal plots of the 2016 and 2017 Tanzanian Agronomy Panel Survey (TAPS 2017; n = 580) with a range of yields and socio-economic contexts (2.10tha-1 – 3.68tha-1). Results suggested that in low resource fields, management factors are subservient to extreme soil degradation while in high resource fields good management such as optimal planting are needed for maximum predicted yield (4.48tha-1; n = 51). Boundary line analysis was conducted, and maximum yield-nutrient response values calculated. The yield gap obtained suggested only up to 60% of locally obtainable yield is reached, highlighting the necessary balance between intensity of resource use and good management for sustainable and sufficient crop production, especially in the case of extreme soil degradation.

Suggested Citation

  • Jan Lietava & Risa Morimoto, 2019. "Regression tree analysis of soil fertility and agro-economic practices and the effects on yield in Tanzania," Working Papers 218, Department of Economics, SOAS, University of London, UK.
  • Handle: RePEc:soa:wpaper:218
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    File URL: https://www.soas.ac.uk/economics/research/workingpapers/file139488.pdf
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    References listed on IDEAS

    as
    1. Msuya, E. E & Isinika, A. C., 2011. "Addressing food self-sufficiency in Tanzania: a balancing act of policy coordination," MPRA Paper 30886, University Library of Munich, Germany.
    2. Jan Willem Gunning & Paul Collier, 1999. "Explaining African Economic Performance," Journal of Economic Literature, American Economic Association, vol. 37(1), pages 64-111, March.
    3. Wiig, Henrik & Aune, Jens B. & Glomsrod, Solveig & Iversen, Vegard, 2001. "Structural adjustment and soil degradation in Tanzania: A CGE model approach with endogenous soil productivity," Agricultural Economics, Blackwell, vol. 24(3), pages 263-287, March.
    4. Subhash C. Ray, 1982. "A Translog Cost Function Analysis of U.S. Agriculture, 1939–77," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 64(3), pages 490-498.
    5. Tittonell, P. & Vanlauwe, B. & de Ridder, N. & Giller, K.E., 2007. "Heterogeneity of crop productivity and resource use efficiency within smallholder Kenyan farms: Soil fertility gradients or management intensity gradients?," Agricultural Systems, Elsevier, vol. 94(2), pages 376-390, May.
    6. Giller, Ken E. & Rowe, Ed C. & de Ridder, Nico & van Keulen, Herman, 2006. "Resource use dynamics and interactions in the tropics: Scaling up in space and time," Agricultural Systems, Elsevier, vol. 88(1), pages 8-27, April.
    7. Ephraim Nkonya & Ted Schroeder & David Norman, 1997. "Factors Affecting Adoption Of Improved Maize Seed And Fertiliser In Northern Tanzania," Journal of Agricultural Economics, Wiley Blackwell, vol. 48(1‐3), pages 1-12, January.
    8. Seyoum, E. T. & Battese, G. E. & Fleming, E. M., 1998. "Technical efficiency and productivity of maize producers in eastern Ethiopia: a study of farmers within and outside the Sasakawa-Global 2000 project," Agricultural Economics, Blackwell, vol. 19(3), pages 341-348, December.
    9. Cornia, Giovanni Andrea, 1985. "Farm size, land yields and the agricultural production function: An analysis for fifteen developing countries," World Development, Elsevier, vol. 13(4), pages 513-534, April.
    10. Ellis, Frank, 1982. "Agricultural price policy in Tanzania," World Development, Elsevier, vol. 10(4), pages 263-283, April.
    11. Florin-Marius PAVELESCU, 2011. "Some aspects of the translog production function estimation," Romanian Journal of Economics, Institute of National Economy, vol. 32(1(41)), pages 131-150, June.
    12. Jonathan Isham, 2002. "The Effect of Social Capital on Fertiliser Adoption: Evidence from Rural Tanzania," Journal of African Economies, Centre for the Study of African Economies (CSAE), vol. 11(1), pages 39-60, March.
    13. Kaliba, Aloyce R. & Verkuijl, Hugo & Mwangi, Wilfred, 2000. "Factors Affecting Adoption Of Improved Maize Seeds And Use Of Inorganic Fertilizer For Maize Production In The Intermediate And Lowland Zones Of Tanzania," Journal of Agricultural and Applied Economics, Southern Agricultural Economics Association, vol. 32(1), pages 1-13, April.
    14. Omamo, S. W. & Williams, J. C. & Obare, G. A. & Ndiwa, N. N., 2002. "Soil fertility management on small farms in Africa: evidence from Nakuru District, Kenya," Food Policy, Elsevier, vol. 27(2), pages 159-170, April.
    15. Ekbom, Anders & Sterner, Thomas, 2008. "Production Function Analysis of Soil Properties and Soil Conservation Investments in Tropical Agriculture," Discussion Papers dp-08-20-efd, Resources For the Future.
    16. Brian Cooksey, 2011. "Marketing Reform? The Rise and Fall of Agricultural Liberalisation in Tanzania," Development Policy Review, Overseas Development Institute, vol. 29, pages 57-81, January.
    17. Kaliba, Aloyce R.M. & Verkuijl, Hugo & Mwangi, Wilfred, 2000. "Factors Affecting Adoption of Improved Maize Seeds and Use of Inorganic Fertilizer for Maize Production in the Intermediate and Lowland Zones of Tanzania," Journal of Agricultural and Applied Economics, Cambridge University Press, vol. 32(1), pages 35-47, April.
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    More about this item

    Keywords

    Regression tree analysis; soil property; Tanzania; agro-economic practice;

    JEL classification:

    • Q10 - Agricultural and Natural Resource Economics; Environmental and Ecological Economics - - Agriculture - - - General
    • Q15 - Agricultural and Natural Resource Economics; Environmental and Ecological Economics - - Agriculture - - - Land Ownership and Tenure; Land Reform; Land Use; Irrigation; Agriculture and Environment
    • Q56 - Agricultural and Natural Resource Economics; Environmental and Ecological Economics - - Environmental Economics - - - Environment and Development; Environment and Trade; Sustainability; Environmental Accounts and Accounting; Environmental Equity; Population Growth
    • R15 - Urban, Rural, Regional, Real Estate, and Transportation Economics - - General Regional Economics - - - Econometric and Input-Output Models; Other Methods
    • R28 - Urban, Rural, Regional, Real Estate, and Transportation Economics - - Household Analysis - - - Government Policy

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