Indexing
All Issues
Submission
Author Guidelines
Reviewers
Editorial Members
Publication Fee
Vol.5 , No. 5, Publication Date: Nov. 22, 2018, Page: 79-89
 of organic pollution (COD) and total lead have been searched for in the different water and sediment samples of the channel. The inventory of the potential sources of chemical pollution of the Chenal, reveals that the garbage dumps littering the lagoon banks, the collectors and the drainage channels of the city of Cotonou, the road and maritime transport, and the dyers of Gbogbanou are the main sources. The physicochemical measurements of the Chenal water monitoring have shown that the values of the recorded temperature, pH, nitrate, nitrite and phosphate do not show statistically a sign of pollution of the studied area apart from some pockets of contamination like the mouth of the SOBEBRA and the Hotel du Lac at the time of wastewater rejection. Besides, the measured values reveal at the threshold of 5% a low transparency (0 to 0.875m), a low level of dissolved oxygen (0.00 to 4.33mg/L), a very high Chemical Oxygen Demand (COD) (669 ± 615 to 997 ± 337 mg O<sub>2</sub>/L) and a high contamination of the water column with ammonium ion (6.84 ± 3.43 at 13.80 mg/L) at the mouth of the SOBEBRA (lake Hotel). In water, the average lead content is 0.258 ± 0.29 mg/L.&picture=http://www.aascit.org/aascit/decorators/img/journal/905.jpg)
| [1] | Magloire Acakpo Nonvignon Gbaguidi, Department of Chemical Engineering and Processes, University of Abomey-Calavi (UAC), Cotonou, Republic of Benin. |
| [2] | Mickaël Vitus Martin Kpessou Saizonou, Department of Chemical Engineering and Processes, University of Abomey-Calavi (UAC), Cotonou, Republic of Benin. |
| [3] | Alassane Youssao Abdou Karim, Department of Chemical Engineering and Processes, University of Abomey-Calavi (UAC), Cotonou, Republic of Benin. |
| [4] | Lucrèce Laleye, Department of Chemical Engineering and Processes, University of Abomey-Calavi (UAC), Cotonou, Republic of Benin. |
| [5] | Aimé Zannou, Department of Chemical Engineering and Processes, University of Abomey-Calavi (UAC), Cotonou, Republic of Benin. |
| [6] | Léonce Firmin Comlan Dovonon, Department of Chemical Engineering and Processes, University of Abomey-Calavi (UAC), Cotonou, Republic of Benin. |
| [7] | Henri Houénoukpo Soclo, Department of Chemical Engineering and Processes, University of Abomey-Calavi (UAC), Cotonou, Republic of Benin. |
The protection of estuarine aquatic ecosystems is essential to the ecological balance of fish species and to a healthy diet for local populations. The Cotonou Chenal in southern Benin is under the influence of several forms of pollution that result for most human activities. This work proposes to know the current state of chemical pollution of the aquatic ecosystem of the Chenal in order to limit the ecotoxicological risks. Monitoring indicators of physico-chemical quality (temperature, pH, conductivity, total dissolved solids, dissolved oxygen, transparency and depth) of organic pollution (COD) and total lead have been searched for in the different water and sediment samples of the channel. The inventory of the potential sources of chemical pollution of the Chenal, reveals that the garbage dumps littering the lagoon banks, the collectors and the drainage channels of the city of Cotonou, the road and maritime transport, and the dyers of Gbogbanou are the main sources. The physicochemical measurements of the Chenal water monitoring have shown that the values of the recorded temperature, pH, nitrate, nitrite and phosphate do not show statistically a sign of pollution of the studied area apart from some pockets of contamination like the mouth of the SOBEBRA and the Hotel du Lac at the time of wastewater rejection. Besides, the measured values reveal at the threshold of 5% a low transparency (0 to 0.875m), a low level of dissolved oxygen (0.00 to 4.33mg/L), a very high Chemical Oxygen Demand (COD) (669 ± 615 to 997 ± 337 mg O2/L) and a high contamination of the water column with ammonium ion (6.84 ± 3.43 at 13.80 mg/L) at the mouth of the SOBEBRA (lake Hotel). In water, the average lead content is 0.258 ± 0.29 mg/L.
Keywords
Chemical Pollution, Water, Chenal, Monitoring
Reference
| [01] | Lalèyè P. (1995). Ecologie comparée de deux espèces du Chrysichthys, poissons siluriformes (Clarotéidae) du Complexe lagunaire lac Nokoué-lagune de Porto-Novo au Bénin. Thèse de Doctorat, Université de Liège, Belgique, 199p. |
| [02] | Aïkpe JFA., Gbaguidi ANM., Godonou J-B., Gbenou JD., Zannou A., Dansou HP. (2017). Short-term impact of PM 2.5 fine particulate pollution on the ventilatory function of adults jogging in Porto-Novo (Benin). International Journal of Physiology, Nutrition and Physical Education, 2 (2): 733-337. |
| [03] | Gbaguidi ANM. (2011). Etude de la distribution et des impacts en zone de culture cotonnière au Bénin : Cas des bassins versants de la rivière Agbado et des plans d’eau des réserves de biosphère de la Pendajri et du W au Niger. Thèse de doctorat de l’Université d’Abomey-Calavi. 242p. |
| [04] | Marchani M., Martin J-L., Marchand M. (1983). Détermination de la pollution chimique (hydrocarbures, organochlorés, métaux) dans la lagune d’Abidjan (Côte d’ivoire) par l’étude des sédiments. I. J. Oceanogr. trop. 20 (1): 23-39. |
| [05] | Toffi DM. (2008). Le climat, l’homme et la dynamique des écosystèmes dans l’espace littoral du Bénin (Afrique de l’Ouest). Université d’Abomey-Calavi, FLASH, Ecole doctorale pluridisciplinaire « Espace, Culture et Développement », Thèse de Doctorat Unique de Géographie-Climatologie, Abomey-Calavi. 245p. |
| [06] | Singbo OPR. (2017). Developpement d’une technique de recherche et de dosage des HAPs et des POCs dans les écosystèmes naturels basée sur la méthode Quechers couplée à la GC et la SM. Mémoire de Master en Management de l’Environnement et Qualité des Eaux. Université d’Abomey-Calavi, FAST, 124p. |
| [07] | Gbaguidi ANM., Dovonon LF., Youssao A., Saizonou M., Djibril R., Mohamed YI., Soclo HH., Fayomi B. (2014). Search of Organochlorine Pesticide Residues (Pocs) in Bodies of Water in Cotton-Growing Area of Benin by GC-ECD. Pak. J. Chem., 4 (2): 49-61. |
| [08] | Youssao A., Soclo HH., Bonou C., Vianou K., Gbaguidi ANM. et Dovonon L. (2011). Evaluation de la contamination de la faune ichthyenne dans le complexe lagunaire Nokoué – chenal de Cotonou par le plomb: cas des espèces Sarotherodon melanotheron, Tilapia guineensis et Hemichromisfasciatus. Int. J. Biol. Chem. Sci., 5 (2): 595-602. |
| [09] | Sagbohan FHGS. (2003). Evaluation de la pollution organique et du pouvoir autoépurateur du lac Nokoué et du chenal de Cotonou (Bénin). Mémoire de DIT Techniques d’aménagement et de protection de l’environnement. CPU/UAC. 76p. |
| [10] | Badahoui A., Fiogbe E., Boko M. (2009). Les causes de la dégradation du chenal de Cotonou. International Journal of Biological and Chemical Sciences, 3 (5): 979-997. |
| [11] | Rodier J., Legube B., Merlet N. (2009). L’analyse de l’eau. 9è édition Paris. DUNOD. 1579p. |
| [12] | Saïzonou M., Youssao A., Gbaguidi M., Dovonon L., Soclo HH., Sohounhoulé D. (2014). Contribution des eaux usées ménagères et des eaux de ruissellement dans la pollution des eaux du chenal de Cotonou au Bénin. International Journal of Innovation and Applied Studies, 9 (1): 293-306. |
| [13] | Chapman D., Kimstach V. (1996). Selection of water quality variables. Water quality assessments: a guide to the use of biota, sediments and water in environment monitoring. Chapman edition, 2nd ed. E & FN Spon, London. |
| [14] | Houngbo SAP., Gbaguidi ANM., Josse RG., Zannou A., Yehouenou BB., Toklo RM., Fatombi J. and Dossou-Yovo P. (2018). Study of the chemical and bacteriological quality of water resources in Hozin, district of the commune of Dangbo in Benin. International Journal of Chemical Studies, 6 (1), 146–160. |
| [15] | Wongla KKS. (2005). Diversité de l'ichtyofaune du chenal de Cotonou en relation avec les modifications environnementales engendrées par les décharges urbaines. Mémoire de DEA. Université d'Abomey-calavi, Faculté des Sciences Agronomiques, 104p. |
| [16] | Dovonon LF. (2008). La pollution des plans d'eau au Benin. DEA en Environnement, Santé et Développement dans la catégorie Géographie. Université d'Abomey-calavi, Bénin. |
| [17] | Houndenou YB., Atinkpahoun CHN. (2003). Etude de la pollution inorganique azotée et phosphorée dans les écosystèmes du lac Nokoué et du chenal de Cotonou: Identification des sources. Mémoire de DIT Techniques d’Aménagement et Protection de l’Environnement. CPU: UAC, 63p. |
| [18] | Issola Y., Kouassi AM., Dongui BK., Biemi J. (2008). Caractéristiques physicochimiques d’une lagune côtière tropicale: lagune de Fresco (Côte d’Ivoire). Afrique Science, 4 (3): 368-393. |
| [19] | Djibril R. (2001). Impact de l'utilisation des engrais chimiques et des pesticides sur la qualité de l'eau de surface dans la réserve de la biosphère de la Pendjabi. Mémoire de fin de formation CPU/UAC, 160 p. |
| [20] | Dovonou F., Aina M., Boukari M., Alassane A. 2011. Pollution physico-chimique et bactériologique d'un écosystème aquatique et ses risques écotoxicologiques: cas du lac Nokoue au Sud Benin. Int. J. Biol. Chem. Sci., 5 (4): 1590-1602. |
