Soil Properties and Soil Conservation Investments in Agricultural Production - a Case study of Kenya’s Central Highlands
This paper integrates traditional economic variables, soil properties and variables on soil conservation technologies in order to estimate agricultural output among small-scale farmers in Kenya’s central highlands. The study has methodological, empirical as well as policy results. The key methodological result is that integrating traditional economics and soil science is highly worthwhile in this area of research. Omitting measures of soil capital can cause omitted variables bias since farmers’ choice of inputs depend both on the quality and status of the soil capital and on other economic conditions such as availability and cost of labour, fertilizers, manure and other inputs. The study shows that: (i) models which include soil capital and soil conservation technologies yield a considerably lower output elasticity of farm-yard manure; (ii) mean output elasticities of key soil nutrients like nitrogen (N) and potassium (K) are positive and relatively large; (iii) counter to our expectations, the mean output elasticity of phosphorus (P) is negative; (iv) soil conservation technologies like green manure and terraces are positively associated with output and yield relatively large output elasticities. The central policy conclusion is that while fertilizers are generally beneficial, their application is a complex art and more is not necessarily better. The limited local market supply of fertilizers, combined with the different output effects of N, P and K, point at the importance of improving the performance of input markets and strengthening agricultural extension. Further, given the policy debate on the impact and usefulness of government subsidies to soil conservation, our results suggest that soil conservation investments contribute to increase farmers’ output. Consequently, government support to appropriate soil conservation investments arrests soil erosion, prevents downstream externalities and assists farmers’ efforts to increase food production and food security.
|Date of creation:||27 Jan 2009|
|Date of revision:|
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- Obare, G. A. & Omamo, S. W. & Williams, J. C., 2003. "Smallholder production structure and rural roads in Africa: the case of Nakuru District, Kenya," Agricultural Economics, Blackwell, vol. 28(3), pages 245-254, May.
- Peter Berck & Gloria Helfand, 1990. "Reconciling the von Liebig and Differentiable Crop Production Functions," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 72(4), pages 985-996.
- Michael D. Frank & Bruce R. Beattie & Mary E. Embleton, 1990. "A Comparison of Alternative Crop Response Models," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 72(3), pages 597-603.
- Berck, Peter & Geoghegan, Jacqueline & Stohs, Stephen, 1998.
"A strong test of the von Liebig hypothesis,"
Department of Agricultural & Resource Economics, UC Berkeley, Working Paper Series
qt0b81x36x, Department of Agricultural & Resource Economics, UC Berkeley.
- Byiringiro, Fidele & Reardon, Thomas, 1996.
"Farm productivity in Rwanda: effects of farm size, erosion, and soil conservation investments,"
Blackwell, vol. 15(2), pages 127-136, November.
- Byiringiro, Fidele Usabuwera & Reardon, Thomas, 1996. "Farm productivity in Rwanda: effects of farm size, erosion, and soil conservation investments," Agricultural Economics of Agricultural Economists, International Association of Agricultural Economists, vol. 15(2), November.
- Fulginiti, Lilyan E. & Perrin, Richard K., 1998.
"Agricultural productivity in developing countries,"
Blackwell, vol. 19(1-2), pages 45-51, September.
- Widawsky, David & Rozelle, Scott & Jin, Songqing & Huang, Jikun, 1998.
"Pesticide productivity, host-plant resistance and productivity in China,"
Agricultural Economics of Agricultural Economists,
International Association of Agricultural Economists, vol. 19(1-2), September.
- Widawsky, David & Rozelle, Scott & Jin, Songqing & Huang, Jikun, 1998. "Pesticide productivity, host-plant resistance and productivity in China," Agricultural Economics, Blackwell, vol. 19(1-2), pages 203-217, September.
- Sherlund, Shane M. & Barrett, Christopher B. & Adesina, Akinwumi A., 2002. "Smallholder technical efficiency controlling for environmental production conditions," Journal of Development Economics, Elsevier, vol. 69(1), pages 85-101, October.
- Christensen, Laurits R & Jorgenson, Dale W & Lau, Lawrence J, 1973. "Transcendental Logarithmic Production Frontiers," The Review of Economics and Statistics, MIT Press, vol. 55(1), pages 28-45, February.
- Berndt, Ernst R & Christensen, Laurits R, 1974. "Testing for the Existence of a Consistent Aggregate Index of Labor Inputs," American Economic Review, American Economic Association, vol. 64(3), pages 391-404, June.
- Gerdin, Anders, 2002. "Productivity and economic growth in Kenyan agriculture, 1964-1996," Agricultural Economics of Agricultural Economists, International Association of Agricultural Economists, vol. 27(1), May.
- Simmons, Peter & Weiserbs, Daniel, 1979. "Translog Flexible Functional Forms and Associated Demand Systems," American Economic Review, American Economic Association, vol. 69(5), pages 892-901, December.
- Hanan G. Jacoby, 1993. "Shadow Wages and Peasant Family Labour Supply: An Econometric Application to the Peruvian Sierra," Review of Economic Studies, Oxford University Press, vol. 60(4), pages 903-921.
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