In the Kokumbo sub-prefecture, groundwater extraction related to gold panning remains a major concern, not to mention the deterioration of its quality. Among the work carried out on water resources, no scientific inte...In the Kokumbo sub-prefecture, groundwater extraction related to gold panning remains a major concern, not to mention the deterioration of its quality. Among the work carried out on water resources, no scientific interest has been shown in groundwater to characterise it. The objective of this study is to contribute to the knowledge of its physico-chemical quality. In situ measurements and physico-chemical analyses using an inductively coupled plasma optical emission spectrometer (ICP-OES) were carried out on five (5) human-powered pump (HPP) water samples and six (6) well water samples collected during low and high water seasons. The results show that the physico-chemical quality of the water, which is sometimes turbid, is satisfactory in terms of the mineralization of the borehole and well water, and the pH of the boreholes, while the temperatures of the two waters and the pH of the wells do not comply with WHO standards. The levels of major ions are recommended for consumption. The waters are classified as predominantly bicarbonate-calcium and magnesium (73%) in the dry season and in the flood season, with an equal split between bicarbonate-calcium and magnesium (45.5%) and chloride-calcium and magnesium (45.5%). The elimination of materials responsible for the turbidity of certain waters by managers or populations is essential for drinking water use. The risk linked to this element means that these turbid waters are not recommended for drinking water.展开更多
The semi-distributed SWAT (Soil and Water Assessment Tools) model was used in this study to model the sediment yield in the watershed of the Aghien lagoon with an area of 365 km<sup><span style="font-fam...The semi-distributed SWAT (Soil and Water Assessment Tools) model was used in this study to model the sediment yield in the watershed of the Aghien lagoon with an area of 365 km<sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, located in the north of the district of Abidjan (South-East from</span><span style="font-family:Verdana;"> C<span style="white-space:nowrap;">?</span>te d’Ivoire). A sensitivity and uncertainty analysis, as well as calibration of the SWAT model, was conducted using the Sequential Uncertainty Adjustment Procedure (SUFI-2) which is one of the programs interfaced with SWAT in the SWAT-Cup package (SWAT-Calibration-Uncertainty</span><span style="font-family:Verdana;"> Programs). Five parameters of the SWAT model were found to be more sensitive to sediment fluxes. These have been modified (calibration) sparingly in order to improve the reproduction of observed sediments data. Two measures were used to assess the uncertainty analysis of the model: P-factor and R-factor. The R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> and Nash-Sutcliffe (NS) coefficients of determination were used to assess the quality of the calibration. The P-factor obtained is 0.58 and the R-factor is 2.28. The NS and R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> coefficients in calibration over the period from June 2014 to January 2015 are 0.51 and 0.86 respectively. These values </span><span style="font-family:Verdana;">indicate correct consideration of uncertainties by the model and satisfactory calibration</span><span style="font-family:Verdana;"> of the SWAT model for solid fluxes. Then, the model was used to simulate the sediment fluxes at the horizons 2040 (2035-2056), 2060 (2057-2078</span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> and 2080 (2079-2100) in order to assess the impact of climate change on sediments in the watershed of the Ag展开更多
文摘In the Kokumbo sub-prefecture, groundwater extraction related to gold panning remains a major concern, not to mention the deterioration of its quality. Among the work carried out on water resources, no scientific interest has been shown in groundwater to characterise it. The objective of this study is to contribute to the knowledge of its physico-chemical quality. In situ measurements and physico-chemical analyses using an inductively coupled plasma optical emission spectrometer (ICP-OES) were carried out on five (5) human-powered pump (HPP) water samples and six (6) well water samples collected during low and high water seasons. The results show that the physico-chemical quality of the water, which is sometimes turbid, is satisfactory in terms of the mineralization of the borehole and well water, and the pH of the boreholes, while the temperatures of the two waters and the pH of the wells do not comply with WHO standards. The levels of major ions are recommended for consumption. The waters are classified as predominantly bicarbonate-calcium and magnesium (73%) in the dry season and in the flood season, with an equal split between bicarbonate-calcium and magnesium (45.5%) and chloride-calcium and magnesium (45.5%). The elimination of materials responsible for the turbidity of certain waters by managers or populations is essential for drinking water use. The risk linked to this element means that these turbid waters are not recommended for drinking water.
文摘The semi-distributed SWAT (Soil and Water Assessment Tools) model was used in this study to model the sediment yield in the watershed of the Aghien lagoon with an area of 365 km<sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;">, located in the north of the district of Abidjan (South-East from</span><span style="font-family:Verdana;"> C<span style="white-space:nowrap;">?</span>te d’Ivoire). A sensitivity and uncertainty analysis, as well as calibration of the SWAT model, was conducted using the Sequential Uncertainty Adjustment Procedure (SUFI-2) which is one of the programs interfaced with SWAT in the SWAT-Cup package (SWAT-Calibration-Uncertainty</span><span style="font-family:Verdana;"> Programs). Five parameters of the SWAT model were found to be more sensitive to sediment fluxes. These have been modified (calibration) sparingly in order to improve the reproduction of observed sediments data. Two measures were used to assess the uncertainty analysis of the model: P-factor and R-factor. The R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> and Nash-Sutcliffe (NS) coefficients of determination were used to assess the quality of the calibration. The P-factor obtained is 0.58 and the R-factor is 2.28. The NS and R</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> coefficients in calibration over the period from June 2014 to January 2015 are 0.51 and 0.86 respectively. These values </span><span style="font-family:Verdana;">indicate correct consideration of uncertainties by the model and satisfactory calibration</span><span style="font-family:Verdana;"> of the SWAT model for solid fluxes. Then, the model was used to simulate the sediment fluxes at the horizons 2040 (2035-2056), 2060 (2057-2078</span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> and 2080 (2079-2100) in order to assess the impact of climate change on sediments in the watershed of the Ag
