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Il progetto di ricerca ANT-Biolm riguardava lo studio dei processi di colonizzazione microbica in ambienti bentonici della Baia Terra Nova (Mare di Ross), attraverso l'analisi del biolm microbico (batteri, microalghe) e dell'insediamento macrobentonico su substrati articiali, nell'intento di determinarne possibili variazioni causate da disturbi naturali o antropogenici (variazioni di salinità o presenza di contaminanti). I biolms microbici, che giocano un ruolo chiave come substrato per l'insediamento larvale di molte specie di invertebrati, costituiscono hot-spots di diversità microbica; è inoltre noto che le comunità microbiche sono capaci di rispondere rapidamente a mutevoli condizioni ambientali, agendo come potenziali \sentinelle" di perturbazioni naturali o antropiche che negli ultimi anni stanno minacciando il biota che popola gli ecosistemi antartici. Il report raccoglie i risultati salienti delle attività scientifiche condotte nel corso del progetto (dati chimico-fisici acquisiti sulla colonna d'acqua , misure di abbondanza, struttura e metabolismo della comunità microbica associata ai substrati artificiali, abbondanze e tassonomia delle comunità fitoplanctonica e fitobentonica, profili di antibiotico-suscettibilità sui ceppi batterici isolati e delle loro attività enzimatiche, caratterizzazione degli invertebrati bentonici del biofouling)

Microbial enzyme activities on organic polymers were tested as possible sentinels of anthropic and natural forcings during a two-year study in two coastal Antarctic areas (Road Bay and Tethys Bay respectively). In Road Bay high proteolytic activity rates were measured at a site impacted by the Italian research station sewage, due to faecal wastes; in Tethys Bay low salinity waters related to glacier presence were characterized by high enzyme activities probably associated to detritus from ice melting.

Il canale tra le isole di Sicilia e Malta si trova in una delle principali rotte marittime del Mediterraneo e in una regione strategica per le piattaforme di estrazione petrolifera, quindi seriamente esposta al rischio di eventi di sversamento di idrocarburi in mare. Ciò può costituire una grave minaccia agli ecosistemi locali e alle attività economiche, tra le quali il turismo e la pesca. I danni derivanti da un eventuale sversamento sarebbero incalcolabili per l'arcipelago maltese, dove le risorse marine ed il turismo rappresentano i principali proventi economici e, in maniera analoga, per la Sicilia. Le misure di prevenzione e di mitigazione, insieme a un rapido intervento e a un processo decisionale stabile e solido in caso di situazioni di emergenza, aiutano a minimizzare i rischi e a ridurre gli impatti. Grazie alla tecnologia radar ad alta frequenza (HF), la rete CALYPSO rappresenta lo strumento essenziale per il monitoraggio delle correnti superficiali del mare in tempo reale. La tecnologia radar HF fornisce uno strumento unico per determinare le correnti superficiali in tempo 'quasi' reale, consentendo l’applicazione efficace di modelli numerici di dispersione d’inquinanti in mare. Tale metodologia permette di prevedere origine e destinazione dell’inquinante attraverso l'assimilazione dei dati nei modelli di circolazione oceanica, o tramite previsioni statistiche delle correnti marine a breve termine. La rete CALYPSO, operativa da agosto 2012, è attualmente costituita da quattro sistemi SeaSonde (CODAR) che funzionano nella banda di frequenza dei 13.5 MHz. Le misure ottenute sono state ampiamente validate utilizzando sia correntometri che drifters che hanno ripetutamente fornito prove evidenti dell'affidabilità dei dati acquisiti. Le osservazioni a lungo termine hanno consentito una nuova descrizione oceanografica dell'area, documentando la presenza di una quantità di caratteristiche finora mai segnalate con un simile dettaglio spaziale e temporale. The Malta-Sicily Channel is located within one of the busiest commercial routes in the Mediterranean Sea. Due to the presence of oil tankers and oil rigs, this stretch of sea is prone to oil spill events (both deliberate or accidental) with potentially significant impacts on the local ecosystems and economic activities, such as fishing and tourism activities. Prevention and mitigation measures are needed to reduce risks and impacts. Within this framework the high-frequency (HF) radar technology is able to monitor in near-real time surface currents and waves, thus representing an extraordinary tool to reduce the impact of marine pollution events. Assimilation of near real-time surface current data into numerical models greatly improves the short-term forecast of sea state conditions and, consequently, the forecast of oil spill movements and fate. This paper describes the characteristics and potential of the CALYPSO HF radar observing system. The network, in operation since August 2012, currently includes 4 SeaSonde (CODAR) HF radars working at 13.5 MHz. The system is able to provide 2D surface current maps of the Malta-Sicily Channel with high resolution over a 3x3 km grid, every hour. Surface currents derived by the CALYPSO system were validated using independent measurements (acoustic current meter and drifters), and their accuracy extensively proven. The long term datasets show unprecedented descriptions of surface currents patterns within the studied area.

Located in one of the main shipping lanes in the Mediterranean Sea, and in a strategic region for oil extraction platforms, the Malta-Sicily channel is exposed to significant oil spill risks. Shipping and extraction activities constitute a major threat for marine areas of relevant ecological value in the area, and impacts of oil spills on the local ecosystems and the economic activities, including tourism and fisheries, can be dramatic. Damages would be even more devastating for the Maltese archipelago, where marine resources represent important economic assets. Additionally, North Africa coastal areas are also under threat, due to their proximity to the Malta-Sicily Channel. Prevention and mitigation measures, together with rapid-response and decision-making in case of emergency situations, are fundamental steps that help accomplishing the tasks of minimizing risks and reducing impacts to the various compartments. Thanks to state-of-art technology for the monitoring of sea-surface currents in real-time under all sea-state conditions, the CALYPSO network of High-Frequency Radars represents an essential and invaluable tool for the specific purpose. HF radars technology provide a unique tool to track surface currents in near-real time, and as such the dispersion of pollutants can be monitored and forecasted and their origin backtracked, for instance through data assimilation into ocean circulation models or through short-term data-driven statistical forecasts of ocean currents. The network is constituted of four SeaSonde systems that work in the 13.5MHz frequency band. The network is operative since August 2012 and has been extensively validated using a variety of independent platforms and devices, including current meter data and drifting buoys. The latter provided clear evidences of the reliability of the collected data as for tracking the drifting objects. Additionally, data have provided a new insight into the oceanographic characteristics of the region, documenting the presence of a number of previously unreported features. The observing network represents an unique opportunity that exploit HF radar in coastal seas to meet Europe's needs for operational mapping of the surface ocean. Additionally, it provides expertise and support for a new generation of scientists and technical staff.

Coastal radars provide information on the environmental state of oceans, namely maps of surface currents at time intervals of the order of one hour with spatial coverage of the order of several km, depending on the transmission frequency. The observations are of crucial importance for monitoring ports and ship tracks close to the coast, providing support for safe navigation in densely operated areas and fast response in case of accidents at sea, such as oil spill or search and rescue. Besides these applications, coastal radar observations provide fundamental support in MPAs surveillance, connectivity and marine population circulation. In the framework of the Italian RITMARE flagship project coordinated by CNR (Consiglio Nazionale delle Ricerche), a coastal radar network has been designed and implemented with a number of innovative characteristics. The network includes both HF and X-band radars, allowing coverage of wide areas with different spatial and temporal resolutions. HF radars cover up to 80 km with a spatial resolution ranging between 1 and 5 km, while X-band radars provide 5 km coverage with a spatial resolution of 10 m. Joining these two capabilities, the RITMARE coastal radar network enables both a highly effective coverage of wide coastal areas and integrated monitoring of different phenomena, thus allowing the collection of current and wave parameters and detection of bathymetries of both open sea and coastal areas. A dedicated action to foster interoperability among data providers has been undertaken within RITMARE; an IT framework is under development to provide software tools for data collection and data sharing. It suggests standard, data format definitions, Quality Control strategies, data management and dissemination policies. In particular, the implementation of tools exploits both standards of OGC (Open Geospatial Consortium) and web services offered to manage, access and deliver geospatial data. Radar data produced in RITMARE by the coastal radar network represent a challenge to the nowadays definition of OGC web services: the network will suggest and test solutions.

The objective of this study was to examine the space and environment variables that contributed to the presence of swordfish in the Strait of Messina during the 2003 and 2004 harpoon fishing activity. The relationships between catches per location and environmental factors (current, moon phase and sea surface temperature) were analyzed using a generalized linear model (GLM). The GLM analysis showed differences in CPUE (catch per unit effort) values in terms of swordfish numbers per location over the 2-year period. The central locations of the Strait were found to be teeming with fish; the CPUE was also higher in these areas during the new and rising moon phases., Sí

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.

The inversion of X-band marine images sequences allows obtaining the sea state parameter estimation and the reconstruction of the wave height evolution [1-4]. This result is possible tanks to the fact that the backscattering from the sea is “visible”, under some conditions, on the marine radar images. These radar signatures, that typically are suppressed because represent a noise (clutter) for the navigation, are the “useful signal” to be processed in order to achieve information about the sea state: peak wave length, period and direction, current speed and direction and the evolution of surface elevation. The backscattering phenomena is due to the Bragg resonance with ocean waves of wavelengths similar to those of the transmitted electromagnetic waves. In particular, the longer waves modulate the backscattering phenomenon and thus they become visible in the “radar” images. As a consequence, the radar image is not a direct representation of the sea state and thus a processing procedure is needed in order to reconstruct the sea state. After a Fourier Transform of the data, a spectral filter is used to erase all the undesired phenomenon via a dispersion relation. The use of the Modulation Transfer Function (MTF) allows the passage from the radar spectrum to sea spectrum; finally, the resulting spectrum is Fourier transformed to return to the space-time domain. A key step of the whole procedure is the generation of the spectral filter. To built the filter the surface currents have to be estimated, if they are not correctly determined the results of the overall inversion are quite poor. This drawback is further increased when the values of the surface current become high or the data are acquired by a moving vessel, since the problem of the determination of the current is quite complicated and particular attention needs the filtering procedure. This work presents an innovative procedure able to estimate the free-surface current values with high accuracy compared to the ones achieved by the standard classical approach based on a least square fitting. The method is based on the maximization of the scalar product between the spectrum of the received signal and a model generated by mean of the dispersion relation considering different surface current values [4]. This allows to enlarge the applicative arena of the sea state monitoring from radar images to the radar platforms on moving ships. The full procedure for the estimation of the sea state parameters has been applied on real data acquired by an X-band marine radar mounted onboard a vessel travelling on the strait of Messina by using this area has been selected due to its strategic location for the navigation and because it is periodically characterized by high currents values.

Il Golfo di Manfredonia è situato nel mare adriatico occidentale, sul litorale italiano che demarca la circolazione adriatica centrale da quella meridionale. Di seguito sono riportate le distribuzioni spaziali delle proprietà fisiche oceanografiche e della concentrazione di clorofilla-a nel Golfo di Manfredonia durante la stagione primaverile. Le caratteristiche generali della circolazione seguono la traccia della salinità, indicando che l’acqua con i valori alini elevati (S>38.65) risale nel centro del gyre dallo strato intermedio occupato dalla LIW. La distribuzione della concentrazione di Chl-a (all'interno di 0.05-0.55 mg Chl-a m-3) era governata dalle caratteristiche idrodinamiche osservate.

Recent studies have assessed that microbial parameters may be used as bioindicators of climate change in the carbon cycle. The carbon fl ux in aquatic environments is ruled by microorganisms that provide both organication and oxidation of the organic matter by means of production and respiration, respectively. Recent studies on the global carbon budget show that not always a coupling between microbial autotrophic and heterotrophic activities exists. Consequently, aquatic environments can act as sink or source of CO2 in relation to productive or degradative processes, respectively. Our working group for more than a decade studying the role of microbial activity in the biogeochimical processes in the deep Mediterranean Sea and in the Antarctic Ocean which are interesting for several search sites. Recently, transitional areas are often studied for resource management and exploitation. Brackish ecosystems are among the most geochemically and biologically active areas of the biosphere and it plays a considerable role in the global biogeochemichal cycle. Some studies have shown that, in lakes with different trophic state, measurements of microbial activities over the organic matter provide ecological information in terms of functional effi ciency of the microbial community that could be useful for resource management. Microorganisms affect signifi cantly the lake biogeochemistry . In fact, owing to their high abundance, biochemical diversity and quick turnover times, they promptly responds to environmental changes and utilize a wide spectrum of nutritional sources. In transitional environments, microbial autotrophic and heterotrophic activities may be balanced or unbalanced in relation to the ecosystem maturity. Consequently, microorganisms can act as sink or source of CO2 in relation to their dominant metabolism, respectively. Nothwithstanding their peculiarities and biodiversity, up to date few research considered microbial community and biogeochemical processes in lagoons that sometimes result characterized by marked diversifi cation of the trophic levels, organic matter turnover and metabolic C budget both at spatial and seasonal scales, with conditions ranging from oligotrophy to eutrophy. The occurrence of seasonal trophic imbalances in these oligotrophic ecosystems confi rm their vulnerability to climate changes.

In the framework of NEMO Project, two multidisciplinary surveys were performed in a deep-sea area in front off Cape Passero (Ionian Sea). Coccoid cyanobacteria, genus Synechococcus and an unidentified group of very small red fluorescing cells were repeatedly observed in the aphotic zones. The cellular abundances were in the order of 103 cells ml-1. Generally the highest concentrations were detected in the epipelagic zone, but significant abundances were achieved also in the meso- and/or bathypelagic zones.

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.

Le aree di transizione sono ambienti estremamente complessi e diversificati, la cui connotazione, oltre che dalla posizione intermedia fra il dominio marino e quello continentale, è definita da una elevata variabilità spaziale e/o temporale delle caratteristiche mesologiche, sedimentarie, trofiche ed ecologiche. Inoltre, la dinamicità dei processi trofici e della funzionalità del comparto primario, determinano, già nel breve-medio periodo, evidenti modificazioni nella composizione e struttura dei popolamenti planctonici e bentonici. L'insieme di queste caratteristiche fa sì che le Aree di Transizione siamo ambienti privilegiati per lo studio dei processi ambientali, in funzione della valenza diagnostica del monitoraggio integrato delle dinamiche evolutive di questi sistemi Sin dagli anni 70 il nostro gruppo di ricerca conduce, in varie aree di transizione della Sicilia, indagini a carattere ecosistemico, mirate alla definizione delle caratteristiche chimico-fisiche delle acque e dei sedimenti (serie temporali di T°C, salinità, ossigeno, tessitura dei sedimenti, ecc.), alla valutazione dello stato trofico (incidenza di Clorofilla, Carbonio organico ed inorganico, Produzione Primaria, Sali nutritivi, ecc.), nonché all'evoluzione spazio-temporale dei popolamenti microplanctonici, fitoplanctonici e bentonici. Il nostro interesse scientifico per gli ambienti di transizione, si è concretizzato nel corso dell'ultimo trentennio, in una serie di progetti interdisciplinari (Progetto Finalizzato Beni Culturali CNR, VECTOR, LOICZ-LaguNet: Italian Lagoon Observational Network, EU-Strategy: Harmful Algal Blooms Monitoring, ARPA- Monitoraggio dei corpi idrici superficiali della Regione Sicilia, ecc.), oltre che in una costante attività di interazione e collaborazione con le Amministrazioni Locali. Nel corso della pluriennale attività scientifica sono state affrontate diverse tematiche di ricerca, quali: Studio dei processi trofici, Effetti dell'inquinamento da idrocarburi sulle comunità bentoniche, Analisi dei fattori di alterazione ambientale, Fattori di stress e crisi distrofiche, Studio dei fenomeni HABs, Particellato sospeso e ruolo della CO2 , ecc.. Nell'ultimo decennio il nostro interesse scientifico è stato rivolto all'analisi comparata dei dati recenti con le serie storiche già acquisite, utilizzando il monitoraggio come chiave di lettura delle dinamiche evolutive dei sistemi di transizione, in funzione di una maggiore capacità di analisi e di interpretazione dei processi globali. Nei progetti attualmente in corso l'approccio ecosistemico di indagine è stato ulteriormente potenziato attraverso una maggiore integrazione con competenze scientifiche di altre sedi IAMC, da cui sono scaturite ipotesi percorribili per una futura programmazione scientifica integrata, finalizzata alla ricerca ed interpretazione di nuovi indici di valutazione ambientale, specifici per questi peculiari ambienti.

The introduced basswood thrips, Thrips calcaratus, undergoes outbreaks on and damages American basswood, Tilia americana, in North America, but is less common on and does not cause significant damage to little-leaf linden, Tilia cordata, in its native European range. A possible explanation is that altered host relationships in North America allow increased exploitation of T. americana. Three experiments were conducted to compare host associations of T. calcaratus between T. americana and T. cordata. In a laboratory choice bioassay, T. calcaratus occupied foliage of both tree species with equal frequency. A field assay conducted in North America revealed an identical trend on planted T. americana and T. cordata seedlings planted in a paired design. In a separate field experiment bud break phenology, peak T. calcaratus emergence, and foliar development showed similar temporal patterns in 10 T. cordata and T. americana sites distributed across the insect's native range of Europe and introduced range of North America. These results suggest that physiological and phenological differences between native and newly acquired Tilia hosts are not likely responsible for the increased impact of T. calcaratus in its introduced range. Rather, temporal escape from natural enemies seems to be the more likely explanation. This is evidenced by the stronger synchrony of the North American predator, Leptothrips mali, with the native basswood thrips, Neohydatothrips tiliae, than with T. calcaratus. Understanding the basis for increased success of T. calcaratus in its introduced range may provide insight into managing this insect in basswood forests in the Great Lakes region.

The distribution and functional diversity of the microbial community were investigated in the Straits of Messina. Total and autotrophic picoplankton and the levels of activity of some enzymes (leucine aminopeptidase, beta-glucosidase and alkaline phosphatase) showed a marked diversification of this ecosystem related to the presence of water masses with different hydrological characteristics.

Physico-chemical, chemical and biological parameters collected in water column during a multidisciplinary cruise in the Gulf of Manfredonia (October 2002) are reported. Two coastal and offshore systems with different biochemical and physical characteristics were highlighted by spatial distribution of observed parameters. The coastal system is characterised by low salinity, and high ammonium and chlorophyll-a concentrations. The offshore system exhibits a well defined isopicnal gradient and high nitrate values localised below the picnocline.