摘要：Forest transitions (FT) occur when socioeconomic development leads to a shift from netdeforestation to reforestation; these dynamics have been observed in multiple countries across the globe,including the island of Puerto Rico in the Caribbean. Starting in the 1950s, Puerto Rico transitioned froman agrarian to a manufacturing and service economy reliant on food imports, leading to extensivereforestation. In recent years, however, net reforestation has leveled off. Here we examine the drivers offorest transition in Puerto Rico from 1977 to 2000 at two subnational, nested spatial scales (municipalityand barrio) and over two time periods (1977-1991 and 1991-2000). This study builds on previous work byconsidering the social and biophysical factors that influence both reforestation and deforestation at multiplespatial and temporal scales. By doing so within one analysis, this study offers a comprehensiveunderstanding of the relative importance of various social and biophysical factors for forest transitions andthe scales at which they are manifest. Biophysical factors considered in these analyses included slope, soilquality, and land-cover in the surrounding landscape. We also considered per capita income, populationdensity, and the extent of protected areas as potential factors associated with forest change. Our resultsshow that, in the 1977-1991 period, biophysical factors that exhibit variation at municipality scales (~100km2) were more important predictors of forest change than socioeconomic factors. In this period, forestdynamics were driven primarily by abandonment of less productive, steep agricultural land in the western,central part of the island. These factors had less predictive power at the smaller barrio scale (~10 km2)relative to the larger municipality scale during this time period. The relative importance of socioeconomicvariables for deforestation, however, increased over time as development pressures on available landincreased. From 1991-2000, changes in forest cover reflected influences from multiple factors, includingincreasing population densities, land development pressure from suburbanization, and the presence ofprotected areas. In contrast to the 1977-1991 period, drivers of deforestation and reforestation over thissecond interval were similar for the two spatial scales of analyses. Generally, our results suggest thatalthough broader socioeconomic changes in a given region may drive the demand for land, biophysicalfactors ultimately mediate where development occurs. Although economic development may initially resultin reforestation due to rural to urban migration and the abandonment of agricultural lands, increasedeconomic development may lead to deforestation through increased suburbanization pressures
关键词：agricultural abandonment; deforestation; forest transition; Puerto Rico; reforestation
