Trophic and Microbial Dynamics in a Mediterranean Transitional Ecosystem (Lake Faro, Southern Italy): Implications for Pinna nobilis Conservation

Transitional water bodies are coastal areas of strategic naturalistic and socio-economic importance, and highly vulnerable to increased anthropic pressure. A monitoring study was performed in the transitional area of Lake Faro (Cape Peloro Lagoon, Italy), where specimens of the threatened species Pinna nobilis (Mollusca, Bivalvia) constitute a resident community, as a part of a wider research program aiming to preserve this organism in the context of safeguarding lake biodiversity. Five surface water samplings with a two-month frequency were carried out at four selected stations, three of which were located in the inner part of the lake and one control station outside, in a canal connecting the lake to the Messina Straits. Trophic conditions (total suspender matter, nutrients and chlorophyll-a) and the main environmental variables (temperature, salinity, dissolved oxygen) were measured. Insights into the total prokaryotic abundance and metabolism via the extracellular enzymatic activities (i.e., leucine aminopeptidase; beta-glucosidase and alkaline phosphatase) were obtained. The dataset indicated that microbial and trophic dynamics were associated with the abundance of the P. nobilis population. These parameters, moreover, proved to represent a suitable tool for characterizing the environmental health status of transitional areas, as well as for implementing new effective strategies for sustainable resource management.