The Zambian Land Evaluation System (ZLES)

Abstract. A Land Evaluation System for rainfed agriculture has been developed in Zambia. It is intended for use in reconnaissance and semi‐detailed land evaluation studies, and works with 74 subqualities, 40 crops and four input levels. The subqualities are rated and converted into constraint classes per input level. The most limiting constraints determine the final suitability class. Expected yields per suitability class and input level are then estimated. The system was calibrated by a field study at four locations. Comparisons were made between expected and actual yields and expected and actual constraints. The range of actual yields was wider than that expected, probably because of variation in management between farmers. The average actual and expected yields were strongly correlated, but chi‐squared tests showed that they were significantly different. The system generally works well in assessing land suitability for crops commonly grown in Zambia.