Social and biophysical factors of the forest transition in the Mixteca Alta UNESCO Global Geopark

Abstract

The analysis of land use and land cover changes represents a key issue for applied geography. In Mexico, even though deforestation prevails at the national level, it coexists with regional processes of forest recovery—the so-called forest transition. Despite an extensive literature on the forest transition in Mexico and in other developing countries, few studies have simultaneously addressed the social and biophysical factors of this phenomenon. Precisely, in the Mixteca Alta region of the Mexican state of Oaxaca, an increase in forest cover has been observed, taking place in the last several decades because of the combination of these factors. In this paper, we analyze land use and land cover changes occurring from 1967 to 2020 in the Mixteca Alta UNESCO Global Geopark (GMA) based on aerial photographs (1967) and satellite images (2020). We found that, during the study period, the area of oak forest increased 59%, pine-oak forest expanded 349%, grasslands declined 39%, agricultural areas decreased 17%, and areas without vegetation diminished 68%. Overall, 5992 hectares of forest were recovered (14.5% of the GMA’s total area). We also determined the main social and biophysical factors associated with this forest transition using three categories of change: no change, reforestation, and deforestation. This analysis was done with 15 meter-resolution raster data. We studied the importance of 21 variables based on a random forest classification. The most important variables associated with the forest transition were distance to the forest, geomorphological landscape, geology, slope, elevation, number of tractors, and mean temperature. The article discusses why the biophysical variables were more important than the social variables.