Multiple Criteria Land Use Analysis

Since the early 1980's, the Food and Agriculture Organization of the United Nations (FAO) and the International Institute for Applied Systems Analysis (IIASA) have been collaborating on expanding FAOs Agro-Ecological Zones (AEZ) Methodology of land resources appraisal by incorporating decision support tools for optimizing the use of land resources. Initially these tools consisted in the application of linear optimization techniques for analyzing land-use scenarios with regard to single objective functions, such as maximizing agricultural production or minimizing the cost of production under specific physical environmental and socio-economic conditions and constraints. Often the specification of a single objective function does not adequately reflect the preferences of decision-makers, which are of a multi-objective nature in many practical problems dealing with resources. Multi-objective optimization approaches address problem definitions and solutions in a more realistic way and have recently been applied by FAO and IIASA in a land resources appraisal study in Kenya. In this study, multi-objective optimization coupled with multi-criteria decision analysis (MCDA) techniques, using the Aspiration Reservation Based Decision Support (ARBDS) approach, have been used to analyze various land use scenarios, considering simultaneously several objectives such as maximizing revenues from crop and livestock production, maximizing district self-reliance in agricultural production, minimizing costs of production and environmental damages from erosion. The main users of the new tool being developed, which combines AEZ and MCDA, are expected to be natural resources analysts and managers, land-use planners, ecologists, environmentalists, economists at national and regional levels, and agricultural extensionists at the local scale.