Induced innovation and land degradation: Results from a bioeconomic model of a village in West Africa

This paper introduces a modeling method which simulates a village's response to population and market pressure. The method combines a recursive and dynamic linear programming model with a biophysical model of soil condition and plant growth that predicts yields and land degradation for different type of land, land use and cropping patterns. The linear programming model simulates farmers' plans aggregated at the village level under constraints of risk aversion, food consumption, land area, soil fertility, soil depth, labor and cash availability. Detailed agroecological factors determine the main processes of land degradation. A large number of technological alternatives, representing different degrees of labor and/or land-saving techniques available in the study areas, are introduced, taking into account their respective constraints, costs and advantages. The method has been calibrated for a village located in the sub-humid region of Burkina Faso. Several simulations are carried out to the Year 2030. The results show that population pressure leads to intensification and investment in land conservation practices but not necessarily to better farm incomes. Increasing market opportunities can play a more positive role in boosting productivity, but for the next decades the best way to increase production per farmer is to let farmers migrate from the highpopulation- density areas to the low-population-density areas because, under the current economic conditions of most Sahelian countries, intensification per hectare is stil more expensive than the fallow system. © 1998 Elsevier Science B.V. All rights reserved.

[1]  H. Ruthenberg.  Farming systems in the tropics , 1973 .

[2]  J. Braun,et al.  Commercialization of agriculture under population pressure: effects on production, and nutrition in Rwanda , 1991 .

[3]  Kjeld Philip,et al.  Ester Boserup: The Conditions of Agricultural The Economics of Agrarian Change under Population Pressure. George Allen & Unwin Ltd. London 1965. 124 sider. 22/6 sh. , 1965 .

[4]  J. Coulter.  Reversing the Spiral: The Population, Agriculture, and Environment Nexus in Sub-Saharan Africa. (Directions in Development.) By K. M. Cleaver and G. A. Schreiber. Washington DC: The World Bank (1994), pp. 293, £17.05, US$18.95. ISBN 0-8213-2760-0. , 1995, Experimental Agriculture.

[5]  Francis N. Gichuki,et al.  More People, Less Erosion: Environmental Recovery in Kenya , 1994 .

[6]  C. Pieri.  Fertilité des terres de savanes. Bilan de trente ans de recherche et de développement agricoles au Sud du Sahara , 1989 .

[7]  G. M. Higgins,et al.  Potential Population Supporting Capacities of Lands in the Developing World , 1984 .

[8]  B. Barbier.  Impact of market and population pressure on production, incomes and natural resources in the dryland savannas of West Africa: bioeconomic modeling at the village level , 1996 .

[9]  E. Boserup.  The conditions of agricultural growth: The economics of agrarian change under population pressure , 1966 .

[10]  John R. W. Smail.  Agricultural Involution: The Process of Ecological Change in Indonesia . By Clifford Geertz. University of California Press, Berkeley and Los Angeles, 1963. Pp. 176. Bibliography, Index. U.S. $4.00. , 1965 .

[11]  Scott R. Templeton,et al.  Population pressure and the microeconomy of land management in hills and mountains of developing countries , 1997 .

[12]  Uma Lele.  Population Pressure, the Environment and Agricultural Intensification: Variations on the Boserup Hypothesis , 1989 .

[13]  Prabhu Pingali,et al.  Agricultural mechanization and the evolution of farming systems in sub-Saharan Africa , 1988 .

[14]  Joyotee Smith,et al.  The Role of Technology in Agricultural Intensification: The Evolution of Maize Production in the Northern Guinea Savanna of Nigeria , 1994, Economic Development and Cultural Change.

[15]  J. Braun,et al.  Commercialization of agriculture under population pressure: effects on production, consumption, and nutrition in Rwanda. , 1991 .

[16]  C. Geertz.  Agricultural involution : the process of ecological change in Indonesia / Clifford Geertz , 1965 .