Geo-spatial analysis of the nitrate contamination of groundwater from diffuse sources

摘要

The paper is accomplished in the framework of the LIFE09 ENV/RO/000612 -CLEANWATER project, which foresees the development of an integrated GIS approach for the management of nitrogen pollution, at watershed level, with emphasis on modelling tools andfield campaign for analyse the nutrients vulnerable zones. The project facilitates the implementation of Community environmental policy (e.g. WFD Nitrates Directive) at local and regional level, creating a complex watershed database for assess the factors, pressures and responses that impact the water resources.The goal of this paper is to analyze the nitrates pollution from agriculture sources, within the Barlad River Basin (Romania), using a GIS approach. In the framework of Cleanwater project, we have analyzed the influence of land use, soil and local conditions on the nitrates level in groundwater, by using field campaign with a multi-parameter portable sounder and GIS approach. The high nitrates concentrations affect the groundwater quality, which is the main source of the drinking water in many rural areas.Eight NUTS 5 administrative units, supposed to be vulnerable to nitrate pollution, and more than 300 domestic fountains have been chosen for these measurements. In order to analyze the influence of agricultural activities on the groundwater quality the measurements have been accomplished in two periods of time (July and November months). Almost 90% of analyses present concentrations greater than the maximum contaminant level (50 mg/l) for nitrates in drinking water. These values have been recorded more in the neighbourhood or inside the villages, than in the agricultural and pasture areas situated between localities.