Impact of Erosive Processes on Sandy Beaches of the Equatorial Atlantic: An Approach Using Geotechnologies Applied to Coastal Management
Coastal works; Coastal vulnerability; Hydro-sedimentary modeling; Coastal land use and cover.
Coastal environments are under intense pressure from various natural and anthropogenic factors. Changes in the coastal landscape, such as erosive processes on sandy beaches, result from hydrodynamic and climatological forces. These are amplified by the disorganized expansion of urban development and tourism, as observed on the northern coast of the Brazilian state of Rio Grande do Norte. This research aims to assess coastal vulnerability associated with erosion in sandy beach stretches subject to anthropogenic pressure in the municipality of São Miguel do Gostoso, located on the Northern Coast of Rio Grande do Norte. It also seeks to determine the role that coastal habitats, such as dunes, beach strips, and vegetation, play in protecting the coastline against erosive processes. A coastal vulnerability analysis was developed by combining remote sensing data and geoprocessing techniques. This allowed for the analysis of historical beach line variation from 1986 to 2023, and the calculation of the Coastal Vulnerability Index using the Integrated Valuation of Environmental Services and Tradeoffs (InVEST) program module. Compared to the initial analysis period (1986-1993), results from more recent years (2014-2023) show an increase in the average mobility of the beach line. There's also an accentuation of minimum and maximum beach line variation rates, especially in areas with higher anthropogenic occupation. It was also found that the dune cover along the coast represents important habitats for protection against erosion risks in the area, and its maintenance is crucial for sustainable urban expansion.