Hydrogeological and isotopic evaluation of aquifer layers and their relation with atrazine presence

The presence of diverse contaminants in groundwater is a matter of concern since the aquifers constitute the major reserve of liquid freshwater of the world. In rural environments issues related to groundwater contamination prevail by the implementation of industrialized agricultural practices. In relation to pesticide uses, atrazine is applied extensively in corn and sorghum crops to control weeds. The objective of this work was to assess the presence of atrazine in the unconfined aquifer and confined aquifer layers located in the Marcos Juarez loessic plain, linking it with the regional hydrogeological model. For this purpose, the hydrological behavior by stable water isotopes (delta H-2 and delta O-18) and radiocarbon ages (pMC) was also evaluated. It is concluded that there are pieces of evidences of the impact of the current agricultural activities on both aquifers, being higher on the unconfined aquifer, that receives modern water recharge and is more linked to human activities.

Automated summary

The presence of diverse contaminants in groundwater poses a threat to the major reserve of liquid freshwater in the world. In rural environments, groundwater contamination is predominantly caused by industrialized agricultural practices. This study aims to evaluate the presence of atrazine in the unconfined aquifer and confined aquifer layers in the Marcos Juarez loessic plain and link it with the regional hydrogeological model. The results indicate that current agricultural activities have an impact on both aquifers, particularly the unconfined aquifer.