Spatio-temporal analysis of vegetation dynamics in new protected areas: Exploring the partial nature reserve of Aghien (southern Côte d'Ivoire)

The Aghien Partial Nature Reserve, located in the district of Abidjan, is a new protected area that requires special monitoring because it is subject to strong urbanization pressure. To analyse the spatio-temporal dynamics of land use at this site, field data was first collected, followed by processing of Landsat OLI/TIRS images of the reserve from 2020 and 2024. Parameters such as the average annual rate of spatial expansion (T), the conversion rate (Tc), the transition matrix and the conversion intensity were then calculated. Finally, a forecast was made for land-use dynamics up to 2032. A total of ten land-use units were identified within the administrative boundaries of the reserve. Among these units, old rubber plantations, fallow land and secondary forests are the most represented plant formations. Over the period from 2020 to 2024, vegetation dynamics are marked by the expansion of secondary forests (Tc = 9.48%; T = 2.26%), young palm plantation (Tc = 15.01%; T = 3.50%) and bare soil (Tc = 18.50%; T = 4.24%). However, the forecast to 2032 shows a significant expansion of fallow land (Tc = 11.66%; T = 0.92%) and secondary forest (Tc = 26.46%; T = 1.96%). This reflects the gradual restoration of floristic diversity in the reserve's landscape. However, given the persistence of certain human activities, the site needs to be monitored.