CONTRIBUTION DE LA GEOSTATISTIQUE MULTIPARAMETRIQUE POUR LA CARTOGRAPHIE DE L’APTITUDE DES EAUX SOUTERRAINES A L’IRRIGATION (CAS DU MOYEN CHELIFF OCCIDENTAL)

Abstract

This work deals with the physico-chemical quality of groundwater intended for irrigation and the prediction of their salinity in the mid-western Cheliff plain. Under a semi-arid climate, irrigation is unavoidable for most crops. As a result, groundwater is under increasing pressure. In addition to the quantitative problem, water quality does not always comply with irrigation standards as defined by individual schools. The evaluation of the quality of these waters was carried out by analyzing 63 boreholes, the aim of which was to find out their irrigation skills. A study on the spatial variation of electrical conductivity was carried out by applying geostatics, the spatial structure of which is determined by studying the variogram, three classes of salinity were found in this plain; (C3) medium quality; (C4) poor quality; and a quality not recommended for irrigation (C5). Water salinity maps were mapped using Arcgis software10.2. The mapping of the salinity of water by ordinary kriging has shown that the class (C3) largely dominant in the plain, It is a class qualified as very high salinity to be used with great care because it has an effect on the soil and the plant, However, the mapping of this salinity by multiparametric geostatistics allowed us to geolocate the location of the three groups in the study area.