Vol.6 No.1 – 2: Contributions to the protection of a lentic system in the tropical region against chemical pollutions: A case study of “Toho Lake” in Southeastern Benin, West Africa

By: Jean Gouvidé GBAGUIDI, Nikita TOPANOU, Jacques FATOMBI, Essegbemon Akpo Moyo, Daouda MAMA, and Taofiki AMINOU  

Abstract

The protection of aquatics ecosystems leads to the biological equilibrium which secures the safe foods from the aquatics products. Toho Lake located to the southeastern of Benin is threatened by human pollution due to the chemical fertilizers, waste housekeeper and both human and animal excrement result agglomeration. The aim of the present study is to Toho lake protection against chemical and bacteriological pollution of these wet ecosystems. Samples of water and sediment were collected and analyzed by HACH DR 3900 after undergone treatment The different analysis results revealed a mean oxygenation of water (4,95 mgo₂/l), the Biochemical Oxygen Demand (21.5 mgo₂/l), the Chemical Oxygen Demand (149, 39 mg/l) with the azote in Nitrate (NO₃:0,18 mg/l), ammoniacal azote (N-NH₄⁺:0,47 mg/l) phosphorous (2,06 mg/l) are very high. The lake is also polluted by fecal matters. The high contents of heavy metals in the sediment show that the sediments of the lake are polluted by the zinc (340 mg/kg), the cadmium (7 mg/kg), the lead (60,75 mg/kg) and the copper (8,25 mg/kg).

Contributions to the protection of a lentic system in tropical region against chemical pollutions Case study of Toho lake in South eastern Benin, West Africa-converted

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