http://http://dspace.unitus.it:80 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. 2013-05-24T10:34:21Z http://hdl.handle.net/2067/1632 Title: Development of a new expendable probe for the study of pelagic ecosystems from voluntary observing ships Authors: Marcelli, Marco; Di Maio, Antonia; Donis, Daphne; Mainardi, Umberto; Manzella, Giuseppe Abstract: Physical and biological processes of the marine ecosystem have a high spatial and temporal variability, whose study is possible only through high resolution and synoptic observations. The Temperature and Fluorescence Launchable Probe was charted in order to answer to the claim of a cost effective temperature and fluorescence expendable profiler, to be used in ships of opportunity. The development of the expendable fluorometer has followed similar concepts of the XBT (a wire conducting the signal to a computer card), but differently from the latter it was developed with an electronic system which can be improved and adapted to several variables measure channels. To reach the aim of a low-cost probe, were utilized commercial components:a glass bulb temperature resistor for the temperature measurement, blue LEDs, a photodiode and available selective glass filters, for the fluorescence measurement. The measurement principle employed to detect phytoplankton’s biomass is the active fluorescence. This method is an in vivo chlorophyll estimation, that can get the immediate biophysical reaction of phytoplankton inside the aquatic environment; it is a non-disruptive method which gives real time estimation and avoids the implicit errors due to the manipulation of samples. The possibility of using a continuous profiling probe, with an active fluorescence measurement, is very important in real time phytoplankton’s study; it is the best way to follow the variability of sea productivity. In fact, because of the high time and space variability of phytoplankton, due to its capability to answer in a relatively short time to ecological variations in its environment and because of its characteristic patchiness, there isn’t a precise quantitative estimation of the biomass present in the Mediterranean Sea. Description: L'articolo è disponibile sul sito dell'editore http://publications.copernicus.org/ 2006-12-31T23:00:00Z http://hdl.handle.net/2067/2060 Title: Campo idrodinamico nella Salina di Tarquinia a supporto di studi ecologici e di soluzioni operative: applicazione di un modello numerico ad elementi finiti Authors: Di Maio, Antonia Abstract: La Salina di Tarquinia è un ambiente paralico sottoposto a vincolo di tutela ambientale fin dal 1980, è designata come Sito di Interesse Comunitario (SIC) e come Zona a Protezione Speciale (ZPS). Negli anni pertanto le finalità della gestione di tale ambiente sono cambiate: dal punto di vista dell’ambiente acquatico si è andata determinando l’esigenza opposta a quella perseguita per la produzione del sale, ovvero si è cercato di regimare il flusso idraulico all’interno delle vasche in modo da mantenerne costante la salinità, allo scopo di salvaguardare gli ecosistemi che si sono venuti a creare. Tale attività è stata delegata a lungo all’esperienza dei “salinari”, cioè a coloro che hanno maturato negli anni un’approfondita conoscenza del sistema; tale esperienza rappresenta una significativa e importante eredità culturale ma è anche esempio di una gestione dell’ambiente eccessivamente personalistica, che dovrà essere supportata, sempre più negli anni a venire, da strumenti oggettivi e possibilmente standardizzati. In linea di principio la comprensione e l’analisi dei flussi di acqua all’interno o lungo gli ambienti paralici in generale, e nella Salina di Tarquinia in particolare, è l’elemento che si presenta come strumento utile per lo studio dell’andamento e dell’evoluzione dei parametri ecosistemici principali; è attraverso i flussi di acqua, infatti, che avviene il ricambio di energia e materia, responsabili della modulazione degli ecosistemi. Il presente lavoro di tesi vuole dare un contributo sia alla verifica dell’applicabilità di un modello idrodinamico ad un’ambiente estremo sia alla comprensione della relazione esistente tra il comparto idrodinamico e confinamento; quest’ultimo parametro è importante dal punto di vista ecologico in quanto responsabile dell’organizzazione delle comunità all’interno delle lagune, e la possibilità di modellarlo matematicamente getta le basi per l’individuazione di un possibile strumento standard di gestione dell’ecosistema della Salina di Tarquinia, applicabile a tutti gli ambienti paralici non interessati da escursioni di marea. Tale strumento è di tipo previsionale, ovvero si basa sulla previsione del flusso che si viene a creare nell’ambiente studiato in risposta alle forzanti meteorologiche. Questo approccio è fortemente innovativo per un duplice motivo: il primo è quello dell’uso di un modello idrodinamico in un ambiente estremo come quello oggetto del presente studio; il secondo è quello del calcolo del confinamento considerando non indici biologici ma indici fisici, ovvero il campo idrodinamico.; The Tarquinia Salt pan is a protected paralic environment since 1980; in particular it is designated as Site of Community Interest (SIC area) and as Special Protection Zone (ZPS area). The finalities of the management of the aquatic environment in the Tarquinia salt pan therefore are changed throughout the years: in the past it was important to obtain an high salinity in the basin and the subsequent deposition of the salt; to the contrary actually, in order to preserve the ecological value of the salt pan, it is necessary to maintain in the basin a constant and not excessively high salinity value. For a long time the management of the Tarquinia salt pan has been guaranteed by technicians who have deepened their knowledge of the system; such experience represents a meaningful and important cultural inheritance but actually it is not sufficient and had to be supported, more and more throughout the years to come, with objective and possibly standardized instruments. In general it is important to understand and to analyze the water circulation, that distributes energy and matter inside the basin and then it has a fundamental effect on the ecosystems conservation. The objectives of the present work are either to test the applicability of a hydrodynamic model to an extreme environment and to study the relationship between hydrodynamic and confinement that is a very important ecological parameter because it is correlated to communities organization. A mathematical model able to describe the confinement according to hydrodynamic circulation can be an useful standard instrument to manage not only the Tarquinia salt pan but also all the paralic environment. This is a strongly innovative approach either because in the past mathematical models have not been utilized to simulate the slow circulation of salt pan and because till now the confinement has been calculated just by means of biological indexes. Really, other researchers have utilized numerical models to study the lagoons circulation but the physical characteristics of the environment were not extreme as the salt pan ones; this means that the value of the hydrodynamic field was not excessively low and however it was more easily reproducible with mathematical models. About the calculation of the confinement using the hydrodynamic field, the first approach dates from 2006 (Frenod and Goubert) but the model proposed by them is too theoretical and it is not applicable to Tarquinia salt pan, even if it gives important directions for future developments. In brief therefore the desidered objective of this work is to propose a new methodology to study paralic environments, with particular attention to the confinement; the results show that the direction is right but they open a new research field actually unknown. Description: Dottorato di ricerca in Ecologia e gestione delle risorse biologiche 2008-03-06T23:00:00Z