ALES: a framework for land evaluation using a microcomputer

Abstract. ALES , the Automated Land Evaluation System, is a microcomputer program that allows land evaluators to build their own knowledge-based systems with which they can compute the physical and economic suitability of land map units, in accordance with the FAO's Framework for Land Evaluation. The economic suitability of a land mapping unit for a land utilization type is determined from the predicted annual gross margin per unit area. Increasing limitations result in increased costs of production, decreased yields, or both. Evaluators build decision trees to express inferences from land characteristics to land qualities, from land qualities to predicted yields, and from land qualities to overall physical suitability. A representative model is described.