Long term monitoring of atmospheric depositions in a PO valley station. Evaluation of environmental effects

The availability of long term data concerning a period of six years has allowed for the first time a detailed study of the trend and evolution of atmospheric depositions, and the evaluation of their interaction with the surrounding environment. Moreover the work is preliminary to a forthcoming study where the local patterns of the exceedances of current deposition over critical loads will be examined. The data concerning Bosco Fontana (province of Mantua - Lombardy) are referred. They are representative of the Po Valley reality, where different anthropic activities, mainly agriculture and zootechnics live together. Average contents of sulphur and nitrogen of wet and dry depositions are 12.6 and 16.1 kg ha−1; average exceedances of atmospheric depositions over critical loads for sulphur, nitrogen and acidity are in the classes 3, 3 and 5 respectively. Parameters of wet and dry depositions have a lognormal and exponential distribution respectively, while pH has two superimposed normal populations.