Dinamica di popolazione di fitoplancton tossico e flora batterica nel basso Adriatico

The coastal areas of the Southern Adriatic Sea, in particular the Apulian ones, may be considered an example of intact ecosystem and represent an ideal term of comparison to other marine ecosystems having higher levels of pollution (Northern Adriatic Sea). In order to evaluate the sanitary levels of this environment, four transects were investigated during two years monitoring (April 1995-March 1997) along the Otranto Channel coasts, by joint reseach groups of the Environmemtal Hygiene Laboratory of the Istituto Superiore di Sanità and the Istituto Sperimentale Talassografico "A. Cerruti" of CNR in Taranto. The study underlines the phytoplanktic and bacterial population dynamics, and the detection of the microbiological water quality along the coast tract Brindisi - Lecce - Otranto - S. Maria di Leuca. The results acquired pointed out population dynamics of some potentially toxic species of Dinophysis genus and Pseudo-nitzschia delicatissima. These depended on the winter nutrient loads due to the ASW (Adriatic Superficial Waters) and to the LIW (Levantine Intermediate Waters). The bacterial community was mainly constituted by genera Aeromonas, Photobacterium, Cytophaga and Pseudomonas. Also the presence of Enterobacteriaceae family was relevant. Among the pathogenic vibrios the most frequently isolated species were Vibrio alginolyticus and Vibrio vulnificus