Author(s)

E. Koji^1,2, O. V. Noah Ewoti¹, F. M. Onana³, S. Tchakonté¹, C. Lontsi Djimeli¹, A. Tamsa Arfao^1,4, G. Bricheux⁵, T. Sime-Ngando⁵, M. Nola^1*

¹Laboratory of Hydrobiology and Environment, Faculty of Sciences, University of Yaounde 1, Yaounde, Cameroon.
²Department of Animal Biology and Physiology, Faculty of Sciences, University of Douala, Douala, Cameroon.
³Department of Aquatic Ecosystems Management, Institute of Fisheries and Aquatic Sciences, University of Douala, Douala, Cameroon.
⁴Microbiology and Biotechnology Laboratory, Saint Jerome Polytechnic Institute, Saint Jerome Catholic University of Douala, Douala, Cameroon.
⁵Université Clermont Auvergne, Campus Universitaire des Cézeaux, Aubière, France.

The abundance dynamic of some freshwater invertebrates in relation with the abiotic factors of the medium was studied from March 2013 to March 2014 on the main streams of the Wouri and Sanaga basins. Individuals of Copepoda, Atyidae, Chironomidae and Physidae were collected, identified and counted. Samplings were carried out monthly; meanwhile measurements of the environmental variables were taken. Results of the physico-chemical analyses revealed that water of the Sanaga basin is globally well oxygenated (77% - 92%) and faintly mineralized (14 - 107 μS/cm), excepted in the stations receiving house-hold pollutants. Inversely, in the Wouri basin, waters are hypoxic with high content of organic matters (27.79 ± 9.43 mg/L). During rainy season (June-September), there is a dilution-dispersion of the organic matter due to stormwaters. Concerning biological analyses, the families of Physidae and Chironomidae were more abundant in urban stations than in stations situated in suburban area, especially during low water level period, showing that they are well adapted to anthropogenic and organic pollutions. The hypoxic conditions of urban waterways do not favor the proliferation of sensitive taxa such as Atyidae and Copepoda. These taxa preferred well oxygenated waters with rapid flow, and are more abundant during rainy season in stations located in suburban area or which are less subjected to anthropogenic disturbances.

Floods, Anthropogenic Pollution, Dilution-Dispersion, Invertebrates, Bio-Assessment

Koji, E. , Noah Ewoti, O. , Onana, F. , Tchakonté, S. , Djimeli, C. , Arfao, A. , Bricheux, G. , Sime-Ngando, T. and Nola, M. (2017) Influence of Anthropogenic Pollution on the Abundance Dynamics of Some Freshwater Invertebrates in the Coastal Area of Cameroon. Journal of Environmental Protection, 8, 810-829. doi: 10.4236/jep.2017.87051.