Dimension Reduction and Analysis of a 10-Year Physicochemical and Biological Water Database Applied to Water Resources Intended for Human Consumption in the Provence-Alpes-Côte d'Azur Region, France

Abdessamad Tiouiouine (1) , Suzanne Yameogo (2) , Vincent Vallès (3) , Laurent Barbiero (4) , Fabrice Dassonville (5) , Marc Moulin (6) , Tarik Bouramtane (1) , Tarik Bahaj (1) , Moad Morarech (7) , Ilias Kacimi (1)

1 UM5 - Université Mohammed V de Rabat [Agdal]
2 INERA - Institut de l'Environnement et Recherches Agricoles [Ouagadougou]
3 EMMAH - Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes
4 GET - Géosciences Environnement Toulouse
5 CRPV-Marseille - Centre régional de pharmacovigilance de Marseille Provence Corse [CHU de Marseille]
6 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)
7 UAE - Abdelmalek Essaadi University [Tétouan] = Université Abdelmalek Essaadi [Tétouan]

The SISE-Eaux database of water intended for human consumption, archived by the French Regional Health Agency (ARS) since 1990, is a rich source of information. However, more or less regular monitoring over almost 30 years and the multiplication of parameters lead to a sparse matrix (observations × parameters) and a large dimension of the hyperspace of data. These characteristics make it difficult to exploit this database for a synthetic mapping of water quality, and to identify of the processes responsible for its diversity in a complex geological context and anthropized environment. A 10-year period (2006-2016) was selected from the Provence-Alpes-Côte d'Azur region database (PACA, southeastern France). We extracted 5,295 water samples, each with 15 parameters. A treatment by principal component analysis (PCA) followed with orthomax rotation allows for identifying and ranking six principal components (PCs) totaling 75% of the initial information. The association of the parameters with the principal components, and the regional distribution of the PCs make it possible to identify water-rock interactions, bacteriological contamination, redox processes and arsenic occurrence as the main sources of variability. However, the results also highlight a decrease of useful information, a constraint linked to the vast size and diversity of the study area. The development of a relevant tool for the protecting and managing of water resources will require identifying of subsets based on functional landscape units or the grouping of groundwater bodies.

Mots clés: hydrochemistry; water resource; hydrogeology; multivariate statistics; France

Domaines: Sciences de l'environnement; Environnement et Société

Abdessamad Tiouiouine, Suzanne Yameogo, Vincent Vallès, Laurent Barbiero, Fabrice Dassonville, et al.. Dimension Reduction and Analysis of a 10-Year Physicochemical and Biological Water Database Applied to Water Resources Intended for Human Consumption in the Provence-Alpes-Côte d'Azur Region, France. Water, 2020, 12 (2), pp.525. ⟨10.3390/w12020525⟩. ⟨hal-02491336⟩