Multidisciplinary study of Cape Peloro brackish area (Messina, Italy)

With the aim of testing the sensibility of microbial compartment to the environmental changes and assessing if they may provide information about the functional changes in the carbon cycle, an interdisciplinary investigation started in 2006 in the framework of VECTOR DIVCOST Project. The surface waters of two small brackish lakes (Ganzirri and Faro), located in the Cape Peloro (Sicily, Italy) transitional area, were seasonally investigated for a two-year period. The changes in the microbial compartment (bacterioplankton, vibrios, exoenzymatic hydrolysis of proteins and polysaccharides, bacterial secondary production (HBP) and community respiration), the trophic state of suspended matter (TSM, POC, PON, C/N) and hydrological characteristics (T°C, Salinity, Oxygen, Fluorescence, NH4, NO2, NO3, PO4), were contextually analyzed. Despite their spatial proximity and reciprocal connection, the two lakes exhibited marked differences in the nutritional input as well as in both carbon budget and trophic level. Notwithstanding this, many of the investigated parameters showed similar trends, which were greatly influenced by the seasonal variations. However, Faro and Ganzirri Lakes didn't always show a simultaneity of functional processes. In fact, some parameters (enzyme activities, vibrios abundances, respiratory activity) displayed temporally coupled trends between the two lakes, whereas for others (POC, PON, HBP, BA) a seasonal shift in Ganzirri Lake was observed.