Soil physical properties of a fertile, poorly drained soil and their adequacy for use in quantified land evaluation

From June to September a study was carried out in the Atlantic Zone of Costa Rica. For modelling three broad categories of soil have been distinguished in the zone; the (1) fertile and (2) unfertile, well drained soils and the (3) fertile, poorly drained soils. For this study descrlptions and physical characterisations were made of the poorly drained soil group; physical data were not yet available for this group. Physical characterization of the fertile, well drained soil has been done by Leurnmens (1993), under banana, and Weitz (1992), under four different forms of land use. The soil data obtained, together with daily climate data frorn the arca, were used for crop growth sirnulations with the PSl23N-rnodel. For writing the paragraphs about geology and about hydrology parts were used from a report by P. Maebe ("Drainage observations in the poorly drained soils", Internal repon Prograrnma Zona Atlantica, LUW-CATIE-MAG).