Publication Date:
2021-06-27
Description:
The hydrology of the Ebrie coastal lagoon in Abidjan area is summarized. The authors describe the oxygenation in that area during the two extreme seasons of the hydrological cycle: the low-water season (March-April) and the high-water season (Sept-Oct). The influences of the continental and oceanic waters, photosynthesis, exchanges with the atmosphere and pollution are considered. The oxigen consumption of primary organic pollution represents from 9 to 12% of the content of the waters that circulates in the area. It is geographically very heterogeneous. The central basin, swept by strong marine and fresh water currents, shows a rather high level of water oxygenation. In the peripheric bays, water circulation and mixing are less important and pollution accelerates the natural eutrophic processes. During the low-water season, a vertical stratification is responsible for a bottom anoxic layer and the deposit of reduced organic silts. On the contrary, supersaturations, up to 200%, are recorded on the surface layer. During the high-water season the break of the vertical stratification sets the loose reduced silts into suspension and partly reoxygenates the bottom waters. A classification of the different areas, based on the oxygen vertical profiles is proposed.
Keywords:
Atmospheric Sciences
;
Ecology
;
Environment
;
Oceanography
;
Pollution
;
Côte d'Ivoire
;
Lagune Ebrié
;
oxygen
;
water oxygenation
;
hydrology
;
water circulation
Repository Name:
AquaDocs
Type:
article
Format:
application/pdf
Format:
application/pdf
Format:
75-118
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