Giuseppe Zappalà

Assessment of the ecological status of transitional waters in Sicily (Italy): First characterisation and classification according to a multiparametric approach

A 1-year cycle of observations was performed in four Sicilian transitional water systems (Oliveri-Tindari, Cape Peloro, Vendicari and Marsala) to characterise their ecological status. A panel of variables among which trophic and microbial (enzyme activities, abundance of hetetrophic bacteria and of bacterial pollution indicators) parameters, were selected. Particulate organic carbon (POC) and nitrogen (PON) and chlorophyll-a (Chl-a) contents defined the trophic state, while microbial hydrolysis rates and abundance gave insights on microbial community efficiency in organic matter transformation and on allochthonous inputs. To classify the trophic state of examined waters, the synthetic trophic state index (TRIX) was calculated. Microbial hydrolysis rates correlated positively with POC and Chl-a, which increased along the eutrophication gradient. The significant relationships among TRIX, trophic and microbial parameters suggested the use of leucine aminopeptidase, alkaline phosphatase and POC as suitable parameters to implement the Water Framework Directive when assessing the ecological status of transitional water systems.

Modeling the dispersion of viable and total Escherichia coli cells in the artificial semi-enclosed bathing area of Santa Marinella (Latium, Italy)

Coastal areas are strongly affected by episodes of fecal contamination due to polluted water inflows from inadequately treated sewages. The present study aims to investigate the dispersion of Escherichia coli in the artificial semi-enclosed bathing area of Santa Marinella (Latium, Italy) through in situ samplings carried out in summer 2012 and the application of a dynamic model. Collected samples were analyzed by the Culture-Based technique and the Fluorescent Antibody method in order to estimate both the viable culturable cells and the total E. coli population, respectively. The in situ datasets were used to test the proposed modeling approach and simulate the behavior of bacteria as particles subjected, or not, to decay. Next, the flushing time and the computation of the Microbiological Potential Risk Area allowed the evaluation of the contribution of physical and biological processes to coliform dispersion and the related potential risk for bathers.

A new generation of coastal monitoring platforms

The need for new instruments and systems for environment monitoring encouraged the development of a network of coastal platforms combining a high versatility with ease of use and affordability. Almost every instrument can be fitted on the platforms, thanks to the large amount of available power provided by both solar panels and wind generators. All the platforms host a pumping system that pumps water from five depths into a measurement chamber where a multiparametric probe is fitted and from where other devices (e.g. samplers or analysers) can draw samples. In situ temperature measurements are provided at the same pumping depths. A colorimetric nutrient analyser and a meteorological station complete the basic equipment. On one of the platforms, a remotely controlled water sampler and an ADCP are also fitted. The data-acquisition and transmission system enables the platform to be controlled remotely using a special macro-commands set. Several examples of use are presented.

Development of an automatic sampler for extreme polar environments: first in situ application in Svalbard Islands

Increased attention has recently been addressed to Arctic ecosystems due to the well-known impact of global warming on the northern polar region. Advanced technologies for marine monitoring are needed to monitor environmental changes, especially those related to ice melting. In the framework of the ARCA project aimed at studying the hydrological cycle and its consequences on the climate in the boreal hemisphere, a first prototype of automatic equipment was specifically designed to perform discrete sampling of waters in the area close to the Kronebreen glacier, in the Svalbard Archipelago. This study reports the results of the first in situ application of this device related to the study of heterotrophic bacterial distribution and functional metabolism. Along a transect from the glacier to offshore, a high culturable heterotrophic bacterial abundance was observed close to the glacier. Significant spatial differences were recorded in the values of leucine aminopeptidase and beta glucosidase enzymatic activities, with high microbial glycolytic activity close to the glacier. The patterns of extracellular enzymatic profiles of the bacterial isolates showed that lipids, proteins and organic phosphates play a major role in bacterial metabolism in this area of the Arctic Ocean.

Mathematical models supporting the monitoring of Civitavecchia harbour (Rome)

Knowledge of the sources and types of pollutants, of the hydrodynamic field and of the health status of the marine ecosystems subjected to stress is needed to monitor coastal marine environments. The building of new piers and docks and the extension of a breakwater in Civitavecchia harbour have required extensive dredging that was authorised by the Minister of Environment with the prescription to monitor the coastal marine ecosystems with reference to Posidonia oceanica and benthic biocenoses. The structure of benthic communities and the health status of P. oceanica meadows are important indicators of the Ecological Quality Status of coastal marine waters (WFD, 2000/60/CE). In 2012, a multi-platform observing system (C-CEMS) was tested taking into account: a) the distribution of benthic biocenoses; b) physical and biological data acquired by fixed stations and periodic in situ samplings; and c) the results of numerical simulations of sediment particle tracking. This approach was used along the coastline of Northern Latium (Italy) between Tarquinia and Santa Severa. The dispersion of suspended and deposited materials calculated by numerical model is strongly related to the decrement of the shoots density of P. oceanica and to changes of benthic community’s structures.

Cost-Effective Technologies to Study the Arctic Ocean Environment

The Arctic region is known to be severely affected by climate change, with evident alterations in both physical and biological processes. Monitoring the Arctic Ocean ecosystem is key to understanding the impact of natural and human-induced change on the environment. Large data sets are required to monitor the Arctic marine ecosystem and validate high-resolution satellite observations (e.g., Sentinel), which are necessary to feed climatic and biogeochemical forecasting models. However, the Global Observing System needs to complete its geographic coverage, particularly for the harsh, extreme environment of the Arctic Region. In this scenario, autonomous systems are proving to be valuable tools for increasing the resolution of existing data. To this end, a low-cost, miniaturized and flexible probe, ArLoC (Arctic Low-Cost probe), was designed, built and installed on an innovative unmanned marine vehicle, the PROTEUS (Portable RObotic TEchnology for Unmanned Surveys), during a preliminary scientific campaign in the Svalbard Archipelago within the UVASS project. This study outlines the instrumentation used and its design features, its preliminary integration on PROTEUS and its test results.

NEW ADVANCED TECHNOLOGY DEVICES FOR OPERATIONAL OCEANOGRAPHY IN EXTREME CONDITIONS

Monitoring the quality of marine ecosystems is a challenge to achieve and preserve their good environmental status. Real time or near real time acquisition and collection of physical, chemical and biological data series describing the health conditions of marine environments is needed not only when pollution episodes occur, to set up proper remediation measures, but also to follow natural variability of water quality occurring at different time scales. The development of advanced systems for environmental monitoring (coastal and offshore buoys and platforms, unmanned or remotely controlled submersible and unsubmersible vehicles, etc.) gave a great contribution to operational oceanography, helping to bypass the limitations and costs of traditional oceanographic surveys. The systems here described constitute an improvement and application of the know-how acquired in the last two decades in the field of advanced systems for environmental investigations. Potential advantages of the new developed system in comparison with previous prototypes are described. A wide range of applications is possible, covering the cases when conventional ‘manual’ sampling is not possible, or dangerous, for example in proximity to glaciers, or when oil spill, toxic algal blooms, waste water must be sampled. As a first test, the developed system has been used in Arctic waters (Svalbard Islands) to evaluate spatial variations in the microbial assemblage. Results obtained indicate that the developed automatic vehicle and water multisampler are a good complement of traditional oceanographic cruises, and constitute a practical low-cost system to obtain data with good spatio-temporal resolution both for the initial characterization and for the study of possible natural or anthropogenic disturbance in water quality.