Rapporto finale sull'impatto del sistema ISWEC nell'area marina interessata (isola di Pantelleria) dal punto di vista idrologico, dei nutrienti e metalli pesanti.

Il presente report tecnico riporta i risultati di un monitoraggio dei parametri fisici e biogeochimici della colonna d'acqua finalizzati a valutare l'eventuale impatto ambientale del sistema ISWEC (Inertial Sea Wave Energy Converter). Il sistema è un convertitore di tipo galleggiante che utilizza l'inclinazione del fianco dell'onda per produrre energia elettrica ubicato all’interno della zona ZPS (Zona a Protezione Speciale) in prossimità dell’isola di Pantelleria (Stretto di Sicilia). I risultati ottenuti hanno evidenziato una variabilità ipotizzabile interna al sistema marino sia per quanto riguarda le principali caratteristiche chimico-fisiche delle acque che per quanto riguarda la componente biogeochimica intesa come nutrienti disciolti e metalli sia disciolti che in fase particolato

OR1.3 Reportistica dei survey effettuati nel Mar Tirreno sud-orientale e Canale di Sicilia: dati disponibili per OR1

In questo report vengono presentati i dati disponibili per la realizzazione delle attività di OR1 del progetto Marine Hazard (geofisica, campionature di sedimento e dati chimico-fisici della colonna d’acqua). I datasets presentati derivano da campagne oceanografiche eseguite dal CNR nel mar Tirreno SE (Semounts Marsili e Palinuro, alti relativi del fondo mare dell’Arco Eoliano) con focus sulla catena vulcanica del Palinuro (Seamounts Palinuro, Glabro, Enotrio, Ovidio). Vengono introdotte, quindi, le rappresentazioni cartografiche dei datasets batimetrici, side scan sonar, campionature del fondo, dati magnetici e dati sismici a riflessione già disponibile e in fase di elaborazione

Community-Level Responses to Iron Availability in Open Ocean Plankton Ecosystems

Predicting responses of plankton to variations in essential nutrients is hampered by limited in situ measurements, a poor understanding of community composition, and the lack of reference gene catalogs for key taxa. Iron is a key driver of plankton dynamics and, therefore, of global biogeochemical cycles and climate. To assess the impact of iron availability on plankton communities, we explored the comprehensive bio-oceanographic and bio-omics data sets from Tara Oceans in the context of the iron products from two state-of-the-art global scale biogeochemical models. We obtained novel information about adaptation and acclimation toward iron in a range of phytoplankton, including picocyanobacteria and diatoms, and identified whole subcommunities covarying with iron. Many of the observed global patterns were recapitulated in the Marquesas archipelago, where frequent plankton blooms are believed to be caused by natural iron fertilization, although they are not captured in large-scale biogeochemical models. This work provides a proof of concept that integrative analyses, spanning from genes to ecosystems and viruses to zooplankton, can disentangle the complexity of plankton communities and can lead to more accurate formulations of resource bioavailability in biogeochemical models, thus improving our understanding of plankton resilience in a changing environment

Speciation of trace metals in seawater: The Mediterranean Sea

Since the early 1970s, marine chemists have gained a first order understanding of the concentrations, distributions and chemical behaviour of trace metals in seawater (TMs). The concentration and distribution of TMs are controlled by a combination of processes including external sources (natural or anthropogenic) of elements delivered by rivers, by wind-blown dust, by hydrothermal circulation while processes removing TMs from seawater include active biological uptake or passive scavenging onto particulate matter with the ultimate sink of TMs in the marine sediments. All these processes are superimposed on the general circulation and mixing of the different marine systems, resulting in the characteristic distribution of each TM. In the last two decades many studies have been performed relatively to ocean chemistry, but, paradoxically, few studies have been carried out in the Mediterranean Sea that may be considered a miniaturised ocean system, where seawater response to environmental perturbations and/or evolution is rapid and generally amplified with respect to the global ocean. The Mediterranean Sea is characterised by i) the presence of all trophic regimes, from oligotrophy to coastal eutrophy, ii) a 3D ocean dynamics and iii) the near desert of Sahara that represents the world’s largest source of Aeolian soil dust. The present work attempts to review the most crucial aspects of TMs ocean chemistry on the basis of accurate sampling and analysis of dissolved [Med] and particulate [Mep] (Cd, Co, Mo, V, Ag, Pb, Ni and Cu for dissolved form and Al, Cu, Ni, Cd, Co, Pb, Mo and Ag for particulate form) from 15 sampling stations where a number of points along vertical profiles were collected during two basin scale oceanographic cruises (TRANSMED, summer 2007 and SESAME-IT4, spring 2008). The results evidence that the Mediterranean distribution of Cd, Cu and Ni (that show a nutrient-like behaviour in the world ocean) is dominated by land and atmospheric inputs rather than biogeochemical cycling. Particularly, although [Cdd] in the Gulf of Cadiz seems directly controlled by biogeochemical processes, in the Mediterranean sea, the external inputs play a primary role on the distribution of this element. The [Pbd] in the Mediterranean Sea, generally shows values in the range of those recorded in the world ocean, without any evidence of scavenging behaviour along the water column. Noteworthy, very high [Pbd] values were measured in the sampling stations of the Gulf of Lyon and in the S-E of the Spain as possible response to inputs from the large Rhone and Segura rivers. These results suggest a key role played by anthropic impact on the marine Lead chemistry of the Mediterranean Sea. The unprecedented collected dataset of [Agd] and [Vd] suggests a primary control of the Western Europe industrialised areas on the distribution patterns of these elements. Particularly, the depletion of [Vd] in the Eastern basin respect to Western part, reflects the different anthropogenic sources of [Vd] in the Mediterranean area. The [Alp] distribution pattern, clearly shows the direct influence of the Sahara dust at basin scale. The most enriched areas well-agree with wind patterns at regional scale that regulate a direct and primary impact of dust on [Alp] distribution at the surface and also along the entire water column. Fine regulation of particulate sinking speed clearly differentiate the easternmost part of the Mediterranean sea, more continuously affected by desert storms with respect to westernmost areas under control of more irregular dust inputs. The collected dataset represents an original contribution to knowledge of the ocean chemistry of the Mediterranean sea and a potential reference for future investigation of biogeochemical cycles of this, often, unexplored marine system. Natural and anthropic forces continuously change the “chemical physiognomy” of the Mediterranean Sea and it is mandatory to deeply explore mechanisms and processes that control the dynamic of the elements at the interface of the ocean with lithosphere, atmosphere, biosphere and “anthroposhere”. This research job is a tentative to add new pieces of knowledge in this complex field of cutting edge science

I test a terra su un impianto pilota per il trattamento delle acque di zavorra - Ballast Water Treatment System - Parte II (Land Test)

Le acque di zavorra, Ballast Water, sono acque portuali prelevate dalle navi mercantili, petroliere, da crociera, etc.. come zavorra per assicurare sicurezza durante la navigazione grazie al bilanciamento della galleggiabilità della nave stessa. I siti di prelievo e di scarico delle acque possono distare anche centinaia di kilometri, ed essere caratterizzate da condizioni ambientali marine simili o molto differenti. Sostanze chimiche, batteri, virus, specie fitoplanctoniche e zooplanctoniche presenti nelle acque del sito di prelievo possono diventare pericolosissimi agenti contaminanti alieni per il sito di scarico, capaci di alterare l’equilibrio dell’ecosistema marino. Il presente lavoro nasce da una collaborazione tecnico scientifica con una società del territorio siciliano, finalizzata alla sperimentazione e validazione di un sistema per il trattamento delle acque di zavorra, ideato da questa azienda, in conformità al D.M. 16 giugno 2010 s.m.i., Ballast Water Treatment System – BWTS. In particolare, questo lavoro segue e completa, in quanto IIa parte tecnico-sperimentale, il rapporto tecnico pubblicato da D’Agostino et al., nel 2013: “La clorazione in situ per il trattamento delle acque di zavorra - Ballast Water Treatment System - Parte I (Normativa e Basic Approval)”. Al suo interno vengono trattate le procedure e le metodologie necessarie sia per la coltivazione degli organismi viventi che per la validazione dei test, messi a punto per le prove a terra, Land Test, sull’impianto pilota

La clorazione in situ per il trattamento delle acque di zavorra - Ballast Water Treatment System

Da più di un decennio gli organismi internazionali, aderenti all'IMO - International Maritime Organization, per la tutela del mare stanno combattendo una importante questione per la salvaguardia degli ecosistemi oceanici, in seguito alla mobilitazione di ingenti spostamenti di acqua di mare e continentali da un paese ad un altro a mezzo di navi mercantili, navi petroliere, navi da crociera, che usano le acque portuali come zavorra per assicurare una corretta linea di galleggiamento e una più sicura navigazione. L’acqua di zavorra, Ballast Water, usata per la stabilizzazione di grandi navi per il trasporto delle merci e dei passeggeri generalmente viene aspirata dal porto di partenza, immessa nei comparti stagni della carena, ed infine scaricata o durante la navigazione o all’approdo di un altro paese. Questa azione di carico e scarico non tiene conto della contaminazione dei mari degli altri paesi sversando, oltre sostanze chimiche, batteri, virus, specie fito-planctoniche e zoo-planctoniche, in modo non controllato e tale da che possano alterare l’equilibrio dell’ecosistema locale. La questione è ancor più grave se si pensa anche alla elevata cinetica di riproduzione di molti ceppi batterici e microalgali che, seppur prelevati in piccole concentrazione, dopo una settimana all’interno delle vasche di zavorra possono concentrarsi anche di 1.000 volte. Ciò permette a questi organismi viventi, con lo scarico della zavorra, di insediarsi nel nuovo habitat e, continuando a riprodursi, compromettere l’equilibrio dell’ecosistema locale. Questi organismi viventi mai visti e tantomeno censiti e monitorati nei nostri mari vengono detti Specie Aliene e sono conosciute anche gli acronimi A.I.S. – Aquatic Invasive Species – e/o HAOP – Harmful Aquatic Organisms and Pathogens. In questo rapporto tecnico si riportano sia gli aspettti normativi nazionali e internazionali volti a mitigare la questione sia la procedura base, basic approval, per l'approvazione della sostanza attiva che si vuole utilizzare per il sitema di trattamento delle acque di zavorra

Determinazione di idrocarburi pesanti in sedimenti e suoli mediante spettrofotometria infrarossa con trasformata di Fourier

Il metodo si basa sulla determinazione degli idrocarburi pesanti mediante spettrofotometria all’infrarosso (FT-IR); in sintesi, il procedimento consiste nell’estrarre il campione con tetracloroetene, nell’effettuare un clean-up su gel di silice finalizzato all’eliminazione delle sostanze polari e nella lettura in FT-IR La concentrazione degli idrocarburi è confrontata con una curva di calibrazione ottenuta con soluzioni di riferimento a concentrazioni note

Chemical and biochemical responses to sub-lethal doses of mercury and cadmium in gilthead seabream (Sparus aurata)

Specimens of Sparus aurata were exposed to sub-lethal concentrations of Hg and Cd for 25 days and the levels of both metals were investigated in organs and tissues. Bioaccumulation of Hg decreased as follow: gills > kidney > liver > skin > muscle, while the order of Cd bioaccumulation was: liver > kidney > gills > skin > muscle. Immediately after exposure, both metals showed the highest bioaccumulation in gills and skin indicating that these organs are reliable targets for biomonitoring studies after short term exposure. Metals introduction caused a significant time-dependent concentrations increase in kidney and liver, while in the muscle a significant in-crease of Hg was recorded only at the end of the experimentation.The effects of exposure were also investigated, at biochemical level, in the liver, which represents the main target of xenobiotics biotransformation and metabolism in fish. Exposed fishes exhibited a reduction of total lipid level, a decrease of polyunsaturated fatty acids (PUFA), together with a MDA increase. This suggests a direct effect of contaminants on oxidative stress induction that, through the MDA increase, altered the membrane fatty acids composition decreasing the PUFA content. As it regards molecular markers related to oxidative stress and lipid metanolism, a significant increase of Nrf2, Hif- 1 alpha and Ampk and a decrease of Fas were observed after exposure to both metals, while an Nf-kB increase was recorded in specimens exposed to Hg, docuemnting a correlation with oxidative stress and consequent metabolism adaptation. Finally, these results suggest the pos-sibility to adopt these biomarkers to explore fish metabolic responses to environmental pollution

A chemical remediation technique for a nearly-total removal of arsenic and mercury from contaminated marine sediments

After decades of industrial exploitation of the coast and consequent contamination of the sites and marine sediments, it became essential to recover the marine ecosystem by remediation methods to remove toxic contaminants. In this work, a remediation method was developed to clean marine sediments contaminated by arsenic (As) and mercury (Hg). The method can be applied to mobile platforms and is based on an environmentally friendly approach designed to minimise further contamination. The method was tested on two artificially contaminated sediments and two real samples collected from two highly contaminated sites in southern Italy, Augusta Bay and Bagnoli Gulf, characterised by high Hg and As concentrations, respectively. The method consists of four steps: washing with sodium hydroxide (NaOH) to remove metals associated with humic acid; Fenton-reaction using α-CycloDextrin (aCD) to stabilise Fe(II) at natural pH and oxidise As (III) and Hg (0 or I); complexation reaction with aCD; and complexation with sodium sulfide (Na2S) to remove Hg as soluble Hg-polysulfides. Compared to other remediation experiences in literature, this technique provides the best removal efficiency for As and Hg (ranging between 26 -71 % and 57–95 %, respectively). Considering the residual concentrations of As and Hg and the contamination threshold fixed by European Regulation for re-use, the treated sediment can be used in several civil and industrial contexts. The presented method operates in line with the principles of the circular economy to preserve natural resources, prevent secondary pollution, and promote the effective re-use of clean environmental matrices (soils, sediments and aqueous solutions), thus minimising landfill waste