The potential of agroforestry in the high rainfall areas of Zambia: a peasant programming model approach

Existing cropping systems in Northern Zambia cause deforestation and soil degradation. To reduce the environmental problems, the potential of alley cropping and pigeon peas replacing the existing cropping systems was analyzed by the use of multi-objective programming models of peasant households. The models were formulated based on the theories of Chayanov and Nakajima which are suitable under conditions of imperfect labour markets. Risk was incorporated in the models in relation to weather and fertilizer supply. The models provide an opportunity to relate key characteristics of new technologies to key characteristics of peasants' preferences and resource constrains. The models may also be used to identify minimum performance levels required for new technologies to be found acceptable.Models of a small male-headed household are presented under varying conditions: for high and low population densities, with and without fertilizer subsidies, and for households with and without access to off-farm employment under high population density conditions.The analysis showed that the alley cropping technology is very unlikely to replace thechitemene system where there is still sufficient woodland for its continuation. The technology may have higher potential in more densely populated areas, where more intensive forms of agriculture are practised and where there is access to inputs such as lime and fertilizer. The removal of fertilizer subsides as a result of the Structural Adjustment Programs, may favour alley cropping because this technology may increase the efficiency of fertilizer use and reduce the need for nitrogenous fertilizers. The potential of the technology depends very much on the management level and location-specific performance of the trees.The pigeon pea technology has high potential if it is accepted as food since it has a very favourable yield per unit of labour, requires no monetary inputs, and can grow, in very poor soils. Pigeon pea also has potential as a cheap source of protein for the urban poor.