Risk management in southern African maize systems

• University of Zimbabwe, Zimbabwe
• Bunda College of Agriculture, Malawi
• CSIRO Sustainable Ecosystems, Australia

Climatic risk, primarily resulting from erratic rainfall, is a major constraint to the development and adoption of improved technologies for smallholders producing maize in southern Africa. Some 70% of maize produced in the region comes from smallholder farms of less than 5 hectares, and virtually the whole area is rainfed. Besides the constant threat of drought these farmers also contend with rapidly declining soil fertility in an economic environment where external inputs are costly and risky to use. Improved technologies adapted for local use are urgently needed to enable production of sufficient maize and other foodstuffs. The technologies must be low-cost, compatible with present practices and clearly not associated with increased risk to farmers if they are to be acceptable.

To assess the risk associated with alternative maize systems under varying climate and soil conditions, including the long-term consequences of the adoption of maize management practices on systems productivity and resource quality.

These alternative practices are being developed through several regional research networks in the region, led by National Agricultural Research Systems (NARSs) and ccordinated by the International Maize and Wheat Improvement Center (CIMMYT). The Rockefeller Foundation-funded Southern Africa Soil Fertility Network will have special involvement. The project team will assess risk by scrutinising farmer risk-management strategies. Team members will link farmer panels to scientists who are using locally adapted simulation models. The panels of farmers will define categories of production risk, acquaint themselves with strategies for managing climatic risk at the farm level and identify climatic patterns that are difficult to manage. The scientists will develop these strategies into scenarios that can be analysed by simulation modelling of multiple cropping seasons. Results from these analyses will be presented to the farmer panels in demonstrations designed to generate debate about the relative attractiveness of a range of technical alternatives.

This project was designed to develop and test a set of tools and methods that would enhance farmer understanding and adoption of improved crop management strategies in environments subject to significant climatic variability and risk. Farmers can now learn quickly through the use of simulation models and other new information technology, which depict the complex and long-term processes of production systems in easily understood ways. Simulation can be used to explore categories of risk identified by farmer groups or NGOs during participatory appraisal. It can also be used to compare the longer-term consequences and the risks associated with continuing farmers' current practices versus introducing alternatives developed by farmers or researchers.

This form of experience can be tailored closely to farmer circumstances. A capacity for this kind of simulation was considered highly suited to African researchers, NGOs, and other purveyors of improved agricultural practices in their quest to meet the needs of resource-poor farmers in the region. This project served as a bridge between research and development, linking CIMMYT's research on maize, soil fertility and resource management with national adaptive research and technology transfer capacity in Zimbabwe and Malawi. It employed the Australian-developed APSIM (Agricultural Production Systems simulator) in an adaptive research mode for technology testing and farmer experimentation in the two countries.

Project reviewers noted that given the complexity of African farming only the principal components of the system can be modelled. However the project should develop a protocol for testing the APSIM model against actual farm-level soils and productivity data, and since the on-farm research work suggested that both manure and phosphorus were key to farmer constraints and decision-making, these two components should be integrated into the ongoing validation work. They stressed the vital necessity of having full confidence in the performance of APSIM before exposing farmers to some of the simulation results, in order to ensure credibility in the eyes of farmers. To this end the project was extended a further six months.