Impact of Climatic and Anthropogenic Factors on the Spatio-temporal Dynamics of Mangroves in the Grand-Bassam Wetland, Côte d'Ivoire

Background: Mangroves in Côte d'Ivoire, particularly in the Grand-Bassam Ramsar Wetland (GBRW), are seriously threatened by human activities and climate change. Since 1989, these pressures have considerably reduced their area, increasing the risk of coastal erosion and flooding.

Aim: This thesis examines the spatiotemporal evolution of Ivorian mangroves under the effect of climate change, focusing on the changes that occurred between 1989 and 2024.

Methodology: The study relies on remote sensing techniques, such as Landsat satellite image classification and the Land Cover Modeler (LCM) module to analyze the spatiotemporal dynamics of mangroves. In addition, socio-economic surveys were conducted among local populations, making it possible to identify the causes and consequences of these transformations. Finally, the collection of physicochemical data on mangrove waters to assess their state under the effect of climate change. The methodology used allows for anticipating actions for better mangrove management, as it enabled us to estimate the area lost over the past 35 years and the risks faced by this area.

Results: The results obtained show a 65.55% decrease in mangrovy cover between 1989 and 2024. Climate factors, such as sea level rise (estimated at +18 cm by 2050), play a major role in this degradation. At the same time, the demand for firewood and urbanization have contributed to unsustainable exploitation of mangrove resources.

Conclusion: Despite conservation efforts, the lack of concrete restoration projects has slowed down attempts at resilience.