Comparative evaluation of urban versus agricultural nitrate sources and sinks in an unconfined aquifer by isotopic and multivariate analyses.

Nitrate (NO) is one of the most widespread contaminants in groundwater primarily due to agricultural activities utilizing N-containing fertilizers and the presence of animal wastes. Hydrochemical and nitrate isotope data (δN-NO and δO-NO) from the unconfined aquifer in the urban area of Del Campillo city and its surrounding rural area with different land-use types, i.e.

Application of isotope techniques to enhance the conceptual hydrogeological model and to assess groundwater sustainability in the Pampean plain in Córdoba, Argentina.

The objective of this work is to enhance the conceptual hydrogeological model in the Río Cuarto River basin by using isotope and hydrochemical techniques. The precipitation pattern, as reflected in the average values of H and O in stations located in the plains and in the mountains, showed an isotope depletion from the East to the West, attributed to continental and altitude effects. Groundwater quality is mainly the result of two controlling factors: lithology and flow distances from recharge.

Genetic diversity of Escherichia coli isolates from surface water and groundwater in a rural environment.

The genetic characteristics among Escherichia coli strains can be grouped by origin of isolation. Then, it is possible to use the genotypes as a tool to determine the source of water contamination. The aim of this study was to define water aptitude for human consumption in a rural basin and to assess the diversity of E.