Analisi della vulnerabilità all'inquinamento da nitrati. Casi studio.

The Agricultural Nitrate Hazard Index method is based on the elaboration of tematic maps, whose topologic overlay in GIS environment results in a synthetic map, the ANHI Map. Aim of the latter document is to compare portion of territory showing different contamination risk. The factor types which come into play in hazard assessment, have to be analyzed. A scoring is assigned to each one, on the base of the weight they assume in the final evaluation. First step is the definition of the hazard factors (FP) and the control factors (FC). The first ones are referred to agricoltural activities which produce or may produce impacts on the aquifes. The nitrogen quantity applied on soil is evaluated. The latter factors are referred to parameters which modify the hazard factors in positive, negative or null way. Both the factors depend on the agronomical practises, climate and landscape. All the procedures are elaborated into a GIS environment. To this purpose, two case histories are briefly delineated here: the Lete River catchment (case A) and the NE sector of the Campania Plain (case B).