Evaluating impact of spatial scales on land use pattern analysis in Central America

The complexity of the relations between land use patterns and their spatial determinants causes the scale of analysis to influence the results. Often, focus is on one aspect of this scale effect, the spatial resolution. This study emphasises the influence of a varying spatial extent on the analysis of land use patterns in six countries in Central America. Statistical techniques are used to determine the relationship between six land uses and a number of potential determining factors, varying both resolution and extent. Results indicate that the effect of spatial resolution, by aggregating a basic grid to larger units, is small in comparison with other similar studies. The effect of a varying extent, by keeping either national boundaries or analysing the entire region at once, on the other hand, is substantial. An unrealistic redistribution of all major land use types, including a large-scale reforestation, is predicted using statistical analysis with the entire region as extent. When expanding the extent to a unit larger than a country, implicit assumptions concerning market mechanisms and national policies are adopted that do not correspond to the actual situation. Despite the existence of the Central American Common Market, it cannot be assumed that any agricultural land use will expand to satisfy an increasing demand in another country. Findings strongly suggest that any modelling effort at regional or global level should incorporate a thorough analysis of the effects of spatial scale on land use change predictions. (C) 2001 Elsevier Science B.V. All rights reserved.