Impact of the shoreline dynamics on the land use of Bargny (Senegal)

Abstract

To provide a solution to the degradation of coastal ecosystems, the rise of salt water in aquifers, the loss of income and the displacement of populations, due to the coastal erosion of the Municipality of Bargny, careful morphological mapping of the dynamics of the coastline was proposed in this study. It made it possible to evaluate, using satellite imagery, the impact of the dynamics of the coastline, 6 km long and located 30 km from Dakar, on the Bargny districts. The data used are mainly Landsat and Sentinel-2 satellite images, acquired from 1980 to 2024 and the Digital Shoreline Analysis System (DSAS) tool.The Linear Regression Method used made it possible to quantify erosion at -0.43 m/year (1980-1990), -1.80 m/year (1990-

2000), -0 .13  m/year (2000-2017) and -0.52 m/year (2017-2024). However, an accretion rate of +2.23 m/year was observed (2000-2017) around the Bargny thermal power station. This dynamic of the Bargny coastline has an impact on land use. Indeed, agricultural land has declined from 55% to 27%, plant cover from 15% to 13% and bare soil from 15% to 11% by 2024. Only built-up areas have increased from 10% to 41%, caused by population growth in this region. Clearly, the design of an integrated morpho-hydrodynamic model in the short, medium and long term is urgently needed to sustainably develop and protect this coastal zone.