Upland rice simulation and its use in multicriteria optimization

However, the conventional method of agrotechnology transfer may be costly and time-consuming, and the farmers" perception of risk within the context of the economic environment in which they function is sometimes a major barrier to adapting high-yielding technologies. The CERES-Rice simulation model reported here is a computer software package designed to aid in the initial selection of new varieties and management practices in various soil types and climatic environments of the tropics and subtropics. Varieties and management practices which look promising in the context of the simulation are the principal technologies to be tried in the field. This procedure is expected to reduce dramatically the cost and time required in agrotechnology transfer. The extent to which farmers are willing to adopt high-yielding technologies depends upon the economic environment of the farm and their perception of risk in this environment. The costs of fertilizer, chemicals, and other inputs required to support high- yielding technologies are not only a financial barrier to the farmers, they greatly amplify the real and perceived levels of risk. A crop failure not only results in a loss of current food supply, it encumbers any future profits of the farmer to pay for lost input resources. A method for assessing profit/risk trade- offs and designing the production system in conformity with these trade-offs is required. This need is translated quantitatively into the simulation-multicriteria optimization technique (SMOT). SMOT is a computer software package that uses the Monte Carlo procedure to explore the space of feasible production technologies and generate those that are non-inferior in the Pareto optimal sense. From the set of Pareto optimal solutions, the min-max optimization is used to identify the technologies that provide the best compromise between profit and a limited class of weather-related risk, when both profit and risk are equally weighted. As a decision support system, SMOT represents a significant step toward the development of a tool for quantifying some of the profit/risk issues that are of practical use to rice production advisers, researchers, and policymakers in the economic analysis of rice farms. (Author abstract)