Evaluation of Chemical Pollution of Seawater in Donaten’s Ecological and Biological Important Area

CHODATON ZINSOU Marthe Dominique^1, , ADJE Adékounlé Hospice Christian¹, DEGBE Cossi Georges Epiphane¹, DOGBEDA Mawulolo Yao Azumah² and SOHOU Zacharie^{1, 3}

¹Institut de Recherche Halieutique et Océanologique du Bénin, Centre Béninois de la Recherche Scientifique et de l’Innovation, Cotonou, République du Bénin

²Regional Marine Centre, University of Ghana, Legon, Republic of Ghana

³Département de Zoologie, Faculté des Sciences et Techniques, Université d’Abomey-Calavi

Cite this paper

CHODATON ZINSOU Marthe Dominique, ADJE Adékounlé Hospice Christian, DEGBE Cossi Georges Epiphane, DOGBEDA Mawulolo Yao Azumah and SOHOU Zacharie. Evaluation of Chemical Pollution of Seawater in Donaten’s Ecological and Biological Important Area. American Journal of Water Resources. 2022; 10(2):68-71. doi: 10.12691/AJWR-10-2-5

Abstract

Donaten’s Ecological and Biological Important Area is subject to anthropogenic pressure; resulting in its pollution. This study has enabled the assessment of pollution of its maritime part with a view to its preservation. Thus, physico-chemical parameters such as color, temperature, pH, dissolved oxygen, oxygen saturation, salinity, TDS were recorded in situ in three different points on the coast, two of which showed evidence potential pollution. Water samples were taken in these points for determination of BOD₅ and COD, concentration of suspended solids, ammoniacal nitrogen, total nitrogen, nitrates, orthophosphate, total phosphorus, copper, zinc, lead and cadmium using standard methods. The results of physico-chemical characteristics recorded, namely temperature (29.8°C to 30.1°C), suspended solids (1.41 to 42.3 mg/L), pH (6.4 to 6.9), dissolved oxygen concentration (5.4 mg/L to 6.2 mg/L), oxygen saturation (80 to 94), salinity (29.8 to 32.1 g/L), TDS (29513 to 31533 mg/L), COD (<5 to 26 mg/L), BOD (< 1 to 18 mg/L), ammoniacal nitrogen (<0.05 to 2.89 mg/L), nitrates (0.27 to 0.32 mg/L), total kjedahl nitrogen (3.8 and 7.1 mg/L), ortho phosphate (0.002 to 0.47 mg/L), total phosphorus (0.73 to 2.2 mg/L), copper (0.01 to 1.13 mg/L), zinc (1.53 to 2.41 mg/L), lead (<0.001 at 0.022 mg/L) and cadmium (0.008 to 0.012 mg/L) revealed that Donaten’s Ecological and Biological Important Area was not polluted with organic and metallic trace elements pollutants. This study could form a basis for further scientific studies.

Keywords

ecological and biological importance area, organic pollution, trace metal pollution

Copyright

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References

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