Characterization of the Origin of Pollutants in Groundwater from Biostatistical Tests: The Case of Catchment Ehania, South-Eastern Côte d’Ivoire

Brou Dibi, Arthur Brice Konan-Waidhet, Felix Koffi Konan, Charles Sagne Yao, Alex Kouadio Zilé, Issiaka Savané, Dago Gnakri

Université Jean Lorougnon Guedé Daloa, Daloa, C?te d’Ivoire.
Université Nangui Abrogoua, Abidjan, Abidjan, C?te d’Ivoire.

DOI: 10.4236/jwarp.2013.512125                

Abstract

The threat of agro-industrial exploitations on the quality of groundwater resources has become a major concern for the world’s population, mainly in agricultural areas. To solve this problem, several methods such as vulnerability to pollutants and statistics methods, have been adopted to protect these groundwaters. In this study, statistical tests were used to determine the likely source of pollutants in the groundwater resources. First, we made a comparative analysis and then analyzed pollutants parameters using Kohonen self-organizing map (SOM) which allows basic on the similarity to help out any correlation between the physic-chemical parameters. To validate these results, a land use map was developed to identify the sources of pollutants in production functions of different activities taking place on the catchment area. The results indicate very high levels of certain pollutants such as NO₃^-, Cl^- and SO₄^2- with generally higher than World Health Organization (WHO) standards values. These high levels observed could be attributed to the generally free nature of aquifers alteration and sedimentary formations in areas of high agro-industrial production. The analysis of the data from SOM method reveals a strong correlation between pollutants (NO₃^-, SO₄^2-,Cl^- ) and conductivity showing the likely origin of these surface pollutants,an origin that is linked to the existence of larges agro-industrials exploitations. These results are reinforced by those of the overlay map of the sampling sites on the land use map, which shows a strong coincidence between high values of pollutants and production areas of the pollutants that are agro-industrial exploitations. These areas of coincidence are observed in the north where found banana’s industrials plantations that are less visible and mostly in the southwest part where is one of the largest oil palm plantations in the world (36,000 hectares).

Keywords

Characterization; Origin of Pollutants; Groundwater; Biostatistical Tests; Catchment Ehania

Conflicts of Interest

The authors declare no conflicts of interest.

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