The concentrations of cadmium, copper, lead and zinc in sediment samples from the Vridi Canal (Harbour area of economic capital of Cote d’Ivoire) were determined to evaluate the level of contamination. All metal conc...The concentrations of cadmium, copper, lead and zinc in sediment samples from the Vridi Canal (Harbour area of economic capital of Cote d’Ivoire) were determined to evaluate the level of contamination. All metal concentrations in sediment samples, except Cu, were greater than the concentration of Upper Continental Crust (UCC). Sediment pollution assessment was undertaken by using Enrichment Factor (EF), geoaccumulation index (I<sub>geo</sub>) and Pollution Load Index (PLI). The enrichment factor (Cd: EF = 20.04;Pb: EF = 3.43;Zn: EF = 1.56) and géoaccumulation index (Cd: I<sub>geo</sub> = 4.29;Pb: I<sub>geo</sub> = 1.81) showed that the sediments were polluted. The Pollution Load Index (PLI > 1) indicated that the sediments of the studied area were heavily contaminated. Based on the comparison with sediment quality guidelines, the concentrations of cadmium, lead and zinc would be toxic to one or more species of aquatic organisms living in the sediments.展开更多
The latest Intergovernmental Panel on Climate Change (IPCC) report shows that sea-level rise, which has been accelerated since the 19th century resulting to the global warming, threatens coastal areas with high popula...The latest Intergovernmental Panel on Climate Change (IPCC) report shows that sea-level rise, which has been accelerated since the 19th century resulting to the global warming, threatens coastal areas with high population growth. A Global Sea Level Observing System (GLOSS) assessment highlighted the lack of data in Africa, and in Côte d’Ivoire in particular. In order to estimate the evolutionary trend of sea level along the Ivorian coast, and to draw up preventive plans to protect properties and populations, we digitized 65 years of historical tidegrams recorded in the Ebrie Lagoon, using the “Surfer” and “Nunieau” software, then processed them using “T-Tide” and “U-Tide” software. The average levels were calculated using the Demerliac filter from complete daily (day and night) recordings for providing a usable database of 31 years of hourly lagoon data from 1979 to 2015. Our results show that a mean water level in lagoon is 1.04 m. The evolutionary trend in sea level, estimated in the lagoon via the Vridi canal, during the rainy season is the most significant at 2.93 mm/year. This is followed by the dry season, with a trend of 2.89 mm/year. The flood season trend is 2.78 mm/year. This suggests that marine water inflows dominate continental inflows. Our results highlight the vulnerability of Côte d’Ivoire’s coasts to the risk of marine submersion.展开更多
文摘The concentrations of cadmium, copper, lead and zinc in sediment samples from the Vridi Canal (Harbour area of economic capital of Cote d’Ivoire) were determined to evaluate the level of contamination. All metal concentrations in sediment samples, except Cu, were greater than the concentration of Upper Continental Crust (UCC). Sediment pollution assessment was undertaken by using Enrichment Factor (EF), geoaccumulation index (I<sub>geo</sub>) and Pollution Load Index (PLI). The enrichment factor (Cd: EF = 20.04;Pb: EF = 3.43;Zn: EF = 1.56) and géoaccumulation index (Cd: I<sub>geo</sub> = 4.29;Pb: I<sub>geo</sub> = 1.81) showed that the sediments were polluted. The Pollution Load Index (PLI > 1) indicated that the sediments of the studied area were heavily contaminated. Based on the comparison with sediment quality guidelines, the concentrations of cadmium, lead and zinc would be toxic to one or more species of aquatic organisms living in the sediments.
文摘The latest Intergovernmental Panel on Climate Change (IPCC) report shows that sea-level rise, which has been accelerated since the 19th century resulting to the global warming, threatens coastal areas with high population growth. A Global Sea Level Observing System (GLOSS) assessment highlighted the lack of data in Africa, and in Côte d’Ivoire in particular. In order to estimate the evolutionary trend of sea level along the Ivorian coast, and to draw up preventive plans to protect properties and populations, we digitized 65 years of historical tidegrams recorded in the Ebrie Lagoon, using the “Surfer” and “Nunieau” software, then processed them using “T-Tide” and “U-Tide” software. The average levels were calculated using the Demerliac filter from complete daily (day and night) recordings for providing a usable database of 31 years of hourly lagoon data from 1979 to 2015. Our results show that a mean water level in lagoon is 1.04 m. The evolutionary trend in sea level, estimated in the lagoon via the Vridi canal, during the rainy season is the most significant at 2.93 mm/year. This is followed by the dry season, with a trend of 2.89 mm/year. The flood season trend is 2.78 mm/year. This suggests that marine water inflows dominate continental inflows. Our results highlight the vulnerability of Côte d’Ivoire’s coasts to the risk of marine submersion.
