Assessing land use/cover changes in Mexico: a wall-to-wall multidate GIS database

A wall-to-wall multidate GIS database was generated in order to carry out the quantification and spatial characterization of land use/cover changes (LUCC) in Mexico. The first step was the elaboration of a wall-to-wall updated to 2000 database on land use/cover compatible with previous cartographic efforts. Previous land use/cover maps from two different dates (the late 1970´s and 1993) were revised, corrected and integrated into a GIS database. In order to improve the reliability of the database, an attempt was made to assess the accuracy of the digitalization procedure and to correct unlikely changes due to thematic errors in the maps. Digital maps were overlaid in order to generate LUCC maps, transition matrices and to calculate rates of conversion. Based upon this database, rates of deforestation between 1976 and 2000 were evaluated as 0.25 % and 0.76 % per year for temperate and tropical forests, respectively.