A village-level economic model of land clearing, grazing, and wood harvesting for sub-Saharan Africa: with a case study in southern Senegal

A village-level dynamic, stochastic, and non-linear programming model, inco rporating both economic and ecological aspects, is developed to study the c omplex woodland degradation processes in the sub-Saharan Africa. The emphas is is on simultaneous accounting of the effects of three major causes of wo odland degradation, namely, land clearing, grazing, and extraction done for wood fuel, poles and charcoal. that has not been attempted before. The mod el is applied at the village level in Senegal and run for the period 1999-2 020. By running different model scenarios, a number of hypotheses are teste d about woodland degradation as measured through loss of vegetative biomass per unit of land. While demographic pressure was found to aggravate the wo odland degradation processes, introduction of improved agricultural technol ogy, higher cotton prices, increased rural wages, and reduced charcoal pric es were found to retard the process of degradation, On the basis of the fin dings of this study, therefore, the role of policy makers in devising appro priate demographic and economic policies to retard the process of woodland degradation appears to be important in the sub-Saharan African nations with conditions similar to those found in Senegal. (C) 2001 Elsevier Science B. V. All rights reserved.