ASSESSING GROUNDWATER VULNERABILITY TO AGRICULTURE CONTAMINATION IN A SEMI-ARID ENVIRONMENT USING SI AND GOD MODELS, CASE OF BABAR BASIN, ALGERIA

The aquifer of the plain of Babar, with a very large area of around 355,000 ha, is of a great economic importance because it is used for irrigation and domestic consumption. The aquifer zone is mainly occupied by agricultural areas characterized by an increasing use of chemical fertilizers, threatening the quality of groundwater. The study of the vulnerability to pollution of this water table was carried out by applying the GOD and SI methods in a GIS environment. The comparison of the vulnerability maps obtained shows that the recovery rates are very different, but they have a certain degree of similarity in space, both methods show a low vulnerability to agriculture pollution. In terms of vulnerability characterization, the GOD method provides more representative information.