Shifting maize cultivation and secondary vegetation in the Southern Yucatan: successional forest impacts of temporal intensification

Shifting cultivation around the Calakmul Biosphere Reserve of Mexico, part of the Mesoamerican Biological Corridor, appears to be intensifying temporally through reductions in crop-fallow cycles, with potential impacts on species diversity in the regenerating forest patches surrounding the reserve. This paper documents the temporal intensity of shifting maize cultivation in the region and links it to the species diversity found in secondary vegetation of different ages following different crop-fallow cycles. It finds that younger secondary growth, which is increasing under intensification, has less diversity in species composition. Simultaneously, the concentration of cultivation practices appears to foster more patches in older and more species-diverse vegetation. The implications for the preservation of the region's forest remain uncertain, however, given the spatial concentration of open lands along two key axes, one which dissects the reserve.