The next paragraphs explain the methodologic process used in this work. DTM was processed to create several relief features maps using filtering and classifying tables with GIS capabilities. A first approach to the study area was carried out in December 1991 with a reconnaissance fieldwork. This led us to get a first knowledge of physic, biologic, social and economic characteristics of The Cape Region. A main step in the methodology to delineate environmental units was the interactive process of screen digitizing.
Black lines are environmental units boundaries.
White lines are the soil unit-mapping. The hillshading map was used like backdrop image. A second fieldwork trip was made in September 1992 in order to check the delineation boundaries of preliminary geomorphic-environmental units. The landscape unit map was crossed against several thematic maps to obtain a digital database that describes area and cover percentage of each thematic class for each landscape. The map of landscape units and its database led, in further phases, to define landuse suitabilities related to an environmental land management approach by means of techniques of multivariate analysis.