In a context of strong dependence of Ivorian populations on surface water resources, the Mé River occupies a strategic position, particularly for the supply of drinking water to the city of Abidjan. However, this resource is facing a growing threat due to the intensification of artisanal gold mining activities within its watershed. This study therefore aims to assess the impact of these activities on the water quality of the Mé River, with a view toward the sustainable management of this resource. The methodological approach first involved a physicochemical analysis of the water resource in relation to the World Health Organization (WHO, 2017) guideline values, followed by a qualitative assessment using contamination and pollution indices based on trace metal elements (TMEs). The results show an alkaline pH (10.2), low mineralization (113.13 µS/cm), and a very high average turbidity (13,115.78 NTU). The analyses also revealed high concentrations of cadmium (Cd; mean: 36.81 µg/L), copper (Cu; mean: 166.72 µg/L), mercury (Hg; mean: 46.31 µg/L), and lead (Pb; mean: 72.5 µg/L), indicating contamination of anthropogenic origin, directly linked to artisanal gold mining activities. The contamination index shows a decreasing ranking of TMEs as follows: ICM (Cd) > ICM (Pb) > ICM (Hg) > ICM (Cu) > ICM (Mn) > ICM (As). Furthermore, the heavy metal pollution index (HPI) reveals that all analyzed water samples (100%) have an HPI value greater than 100, indicating a high pollution risk and rendering the water unsuitable for use.

The sensitivity of subtropical African river basins to possible future climate change is a matter of some concern. In Ivory Coast, previous works on climate change impacts predict a decrease in annual average water resource by the 2080s between 6.9% and 8.4%. This is a potentially serious issue because of a series of historical resource management decisions that have increased dependence upon water use, such as through major dam building schemes. This paper focuses upon the Buyo Lake catchment, a central resource for the Ivorian people with the aim of providing future water resource scenarios, under climate change so as to develop appropriate adaptation policies. The study applied simulations from the UKMO climate model, HadGEM1 from the ENSEMBLES project 2009, with the A1B emissions scenario in continuous simulation. Daily climate data such as rainfall, temperature, wind speed and relative humidity were input to the SWAT hydrological model. The simulations were performed after model calibration. Analysis focuses on the periods 1950-1979 (baseline), 2035-2064 (2050 horizon) and 2064-2093 (2080 horizon).The results showed that the entire basin of Buyo could experience a serious temperature elevation of +1.34