A multidisciplinary study of the Cape Peloro brackish area (Messina, Italy): characterisation of trophic conditions, microbial abundances and activities

Abstract

In the framework of the VECTOR DIVCOST Project, a 2‐year investigation was started in 2006, with the aim of testing the sensibility of microbial parameters to environmental changes and of assessing whether they can provide information about functional changes in the carbon cycle. The investigation was performed in the surface waters of two small brackish ponds (Ganzirri and Faro), located in the Cape Peloro transitional area (Sicily, Italy). The seasonal changes in both the microbial compartment [bacterioplankton, vibrios, exoenzymatic hydrolysis of proteins and polysaccharides, bacterial secondary production (HBP) and community respiration] and the trophic state of suspended matter [total suspended matter (TSM), particulate organic carbon (POC), particulate organic nitrogen (PON), C/N] were analysed in relation to the hydrological characteristics [temperature, salinity, oxygen, fluorescence, NH4, NO2, NO3, PO4]. Despite marked differences in the nutritional input and the diversification in both carbon budget and trophic level, the two ponds show similar trends in many of the investigated factors, hardly influenced by seasonal variations. Temporally coupled trends were observed for some parameters (enzyme activities, vibrios abundances, respiratory activity), whereas others (POC, PON, heterotrophic bacterial production, bacterioplankton) showed a seasonal shift between the two lakes. The different behaviour found for the some biotic parameters suggests that their response to environmental conditions may be modulated differently between the two lakes, which, despite their spatial proximity and reciprocal connection, do not always show contemporaneous functional processes.

Assessment of Electrolytes and Metals Profile of the Faro Lake (Capo Peloro Lagoon, Sicily, Italy) and Its Impact on Mytilus galloprovincialis

“…The application of ANOVA showed significant increase in the saturation percentage of O 2 in winter, while, the pH values increase during summer months. The water parameters values followed the classical seasonal trends also reported in other study conducted in the same area, with minimum of conductivity and temperature in winter and maximum in summer, high oxygen levels over than 90% of saturation and pH in natural range throughout the survey.…”

“…The ‘high anthropic pressure’ in this area, mainly, depends on the presence of several molluscs farming activities and the urbanization process that affected the area in the last decades . Faro Lake is one of the most peculiar coastal basins around the Mediterranean (see Study Area in Experimental Section ) . The high anthropic pressure can lead to environmental contamination; this latter in the marine environment is explicitly recognized in the current European legislation.…”

Comparative hydrodynamics of 10 Mediterranean lagoons by means of numerical modeling

“…There are no direct fluvial inputs into the lagoons and major freshwater inputs derive from nonpoint civil discharges [Leonardi et al, 2009].…”

Pseudodiaptomus marinus Sato, 1913, a new invasive copepod in Lake Faro (Sicily): observations on the swimming behaviour and the sex-dependent responses to food

“…The active motion behaviour of males and females is characterized by a high percentage of time spent cruising, which is considered optimal when foraging at low turbulence levels (Visser et al 2009), a condition likely encountered in Lake Faro with its almost stable stratification (Leonardi et al 2009 and references therein). In addition, the high abundance of food resources, together with a modest mixing rate and appropriate temperature (between 10°C and 28°C) and salinity ranges in Lake Faro (between 34 and 37, Pansera 2011), have likely provided the newly introduced P. marinus a suitable environment for settling.…”