Trace element distribution and enrichment in the stream sediments of the lake Togo watersheds (south of Togo)

Akouvi Avumadi (1, 2) , Kissoa Gnandi (1) , Jean-Luc Probst (2)

1 Université de Lomé [Togo]
2 LEFE - Laboratoire Ecologie Fonctionnelle et Environnement

To evaluate the level of sediment contamination in watershed of lake Togo (south of Togo), the concentrations of twelve trace elements, TE (As, Sn, Cr, Co, Ni, Cu, Zn, Zr, Cd, Pb, Th, U) are analyzed using inductively coupled plasma-mass spectrometry (ICP-MS) in eighteen stream sediment samples from Zio and Haho rivers draining into the lake Togo and from lake Togo itself. The results obtained allow to characterize each sediment sample by its TE geochemical distribution pattern. Average TE concentration in the finest fractions (< 63 μm) is ranked from the hightest to the lowest content: Cr>Ni>Zn>Cu>Co>Pb>Th>Sn>U>As>Cd. The degree of contamination of these stream sediments is evaluated by calculating sediment quality parameters such as enrichment factors (EF), anthropogenic and naturel contribution. Globally, 70% of TE have an EF lower than 1.5, particularly for As, Sn, Co, Cu, Zn, Pb, Th and U. However, 30% of the samples are more contaminated (1.5

Mots clés: Trace metals; Stream sediments; Enrichment factor; Labile fraction; Natural and anthropogenic contributions

Domaines: Ecologie, Environnement

Akouvi Avumadi, Kissoa Gnandi, Jean-Luc Probst. Trace element distribution and enrichment in the stream sediments of the lake Togo watersheds (south of Togo). Advances in Ecological and Environmental Research, 2019, pp.1-28. ⟨hal-02134690v2⟩