Ismaïla Ouattara^1,, Moussa Ouedraogo¹, Léréyaha Coulibaly¹, Kouadio Assemien François Yao¹, Sana Dominique Tuo¹, Zié Ouattara¹, Amidou Dao², Bamory Kamagaté²

This study aims to highlight the impact of mining activities on the morphological dynamics of a sub-watershed of the Cavally River at Ity. To achieve this, a remote sensing-based monitoring of land use and land cover changes was carried out in conjunction with an assessment of morphological alterations of the Cavally River over the same period. Analyses were performed using Landsat TM, ETM+, and Sentinel-2 imagery from the years 1994, 2004, 2014, and 2024. The results revealed significant degradation of riparian vegetation in favour of agricultural and extractive activities, leading to alterations in the morphological parameters of the Cavally River. The regression of vegetation was associated with the expansion of settlements, bare soils, and cultivated land. The study highlighted deforestation and soil stripping processes driven by mining operations. The most significant morphological changes were observed along the river reach near the Ity mine. Here, the sinuosity index decreased from 1.79 to 1.24, resulting in the loss of three meanders and a transformation of a meandering reach into a sinuous one.The floodplain was redefined from 2024 onwards due to river training works that restricted left-bank lateral migration along the same reach. Mining operations by the SMI intensified over the last decade (2014–2024) within the Cavally River floodplain. These activities have impacted the lateral connectivity of the river, as evidenced by an increase in the confinement index from 17.89 to 39.68 between 2014 and 2024. Fluvial dynamics reveal an alternation between erosion and accretion processes. Over the three-decade period, the general trend has been one of erosion along river sections affected by both artisanal and industrial mining activities, due to bank artificialisation and sediment extraction for alluvial mining purposes. This underscores the need to monitor, mitigate, or restore the impacts of these activities on river systems.

geomorphology, human modification, riparian vegetation, sinuosity, confinement index, gold mine, Cavally river