Contribution of Richard A. Vollenweider toward understanding eutrophication of the coastal Adriatic Sea

Abstract

The main scope of the work of R. A. Vollenweider in Italy, that is to say his principal scientific merit, was to critically examine the cause-effect relationships related to the manifestations of the eutrophication phenomenon. These relationships were observed in the NW Adriatic Sea over more than 20 years, along the Emilia Romagna coast, an area strongly affected by Po river inputs, the principal Italian river (Vollenweider et al., 1992). In particular, he stressed the need to examine the integrated system, and to consider both scientific and socio-economic issues as interrelated. Accordingly, coastal waters and their catchment areas with related nutrient loads represent the total system, of which the natural, anthropogenic and socio-economic components are the respective subsystems. In more practical terms, he suggested nutrient load assessment based on the different sources of N and P, to prepare an inventory of all these sources according to types and quantity released, and in terms of pathways of transfer and input-output fluxes. In this way it was finally possible to reach a first realistic evaluation of N and P mass balance across the various productive compartments.