New Methodology for the Identification of Nitrate Contamination from Agricultural Sources

Modern agriculture appears to have a very diversified impact on the soil not only for the crops used but also for the type of fertilizer used. One of the least studied impacts is that on the soil microbiome. Maintaining a stable soil microbial community structure is crucial in preserving soil production potential and overall soil health. Various nitrogen (N) addition strategies induced changes in soil physicochemical properties which are correlated with alterations in microbial community structure and partial microbial abundance, thereby displaying differences in carbon and nitrogen use efficiencies. Therefore it becomes important to analyze how the microbiology of the soil and the effects of the fertilizers used can vary. The current European legislation (Directive 91/676/EEC) and national legislation (Legislative Decree no. 152/2006) set the limits for contamination of groundwater without determining a very precise methodology on how to analyze these compounds and how to identify their actual source. The analysis system presented is an absolute innovation as it allows two different types of integrated analysis (punctual and spatial) through the processing of chemical and microbiological data of both groundwater and soil. The identification of the source of contamination occurs following the complete analysis of all processing phases through the Bottom-up methodology, first identifying the sites and the nitrogenous form that determines groundwater contamination, continuing with the analysis of the different information layers and the analysis of the data collected including microbiological verification. The spatial analysis is processed by the system at the conclusion of the specific investigation. The system creates correlations between the different sites analyzed on the basis of the possible groundwater interrelationships of the points and following the direction of the groundwater and the speed of movement of the groundwater (preset data). The System also allows a temporal analysis of the contamination in order to be able to define whether the contamination is more or less recent.