Multi-criteria approach for the environmental impact assessment of inland aquaculture.

Trout farming, that represents the most important sector for aquaculture inland production in Italy, can cause negative effects on aquatic ecosystems. Recently, in the framework of Water Frame Directive 2000/60/EC and national law DL 152/2006, concerning the sustainable uses of water resources, multi-criteria approaches have been suggested to evaluate the impact of fish farming on aquatic ecosystems. In this study trout farms of central Italy were selected to investigate the effects of their effluents, on receiving water bodies using a multi-criteria approach based on physico-chemical parameters, microbiological and macrobenthonic indicators, detected in sampling stations located upstream/downstream the trout farm. Moreover, antibiotic susceptibility against antibiotics allowed and/or forbidden by current law (D.lgs 193/56/06) was tested on E. coli strains. The results indicate variations of chemical parameters and biological indicators from upstream to downstream sites in some of the investigated farms. Antibiotic resistance of E. coli strains suggested a large use of tetracycline and a possible past use of chloramphenicol. This study represents a first contribute to the knowledge of fish farm impacts on aquatic systems in Central Italy.

Microbiological indicators and sediment management.

The Water Frame Directive 2000/60/CE underlines the importance of sediments and requests the creation of a European net (SedNet) for their management. Sediments play an important role for the river basin and offer a variety of habitats to many aquatic organisms. Microorganisms, such as Clostridia, are indispensable for a lot of symbiotic and pathogenic relationships with higher organisms and the disappearance of these communities could cause extinction of many species. Thus, Clostridia communities represent the most suitable microbiological indicators to characterize the ecological quality of sediments. The creation of SedNet may make it possible to develop a series of best recommendation in sediment management.

[Surface water pollution and microbiological indicators]. / La contaminazione delle acque superficiali e gli indicatori microbiologici.

Surface waters must undergo careful quality assessment before being used as drinking water. Contamination with wastewaters, whether treated, untreated or partially treated, is a risk to public health. Most waterborne infections are caused by ingestion of contaminated water, but contact or inhalation also represent a risk. In industrialized countries, epidemic episodes are mainly due to the spread of new agents or newly identified infections (Arcobacter, Norovirus, Cryptosporodium, Giardia, etc.). To determine the microbial quality of water environments, the latest regulations identify three different groups of indicators according to their contaminating role: faecal, processing, and model or index organisms. No single organism is an adequate indicator of the diverse conditions of water environments. Thus, it is necessary to accurately identify specific indicators.