Landscape Change and Associated Increase in Habitat Fragmentation During the Last 30 Years in Coastal Sand Dunes of Buenos Aires Province, Argentina

Abstract

The Eastern Barrier of Dunes (EBD) and Southern Barrier of Dunes (SBD) extend along the coast of Buenos Aires province, Argentina. These regions have been severely altered by anthropic activities for years, mainly through the development of cities and afforestation with exotic species. We quantified the effect of anthropic activities on the landscape of coastal dunes, evaluating its temporal evolution during the last 30 years. Using Landsat satellite images from 1985, 1996, 2005, and 2015, we performed supervised classifications and obtained thematic maps for coastal dune barriers. Over these maps, we quantified the main classes of natural habitats and anthropic environments and analyzed changes in their extent and arrangement over time. Temporal analyses showed a gradual replacement of anthropic environments over natural habitats. During the last 30 years, the area impacted by anthropic activities went from 13 to 31.7% on the EBD and from 3.6 to 5.9% on the SBD. In the SBD, fragmentation along the main natural habitats increased over the years, whereas fragmentation along the EBD, although higher than that in SBD, remained constant through time. Drastic reductions of the extent of natural habitats were recorded at or near areas where anthropic environments developed. Both coastal dune barriers showed a clear advance of anthropic fragmentation over coastal dune habitats, with EBD being the most impacted by human activities.