giorgio tranchida - Profile on Academia.edu (original) (raw)

Papers by giorgio tranchida

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

Heliyon

The integrated Marine Hazard webGIS platform for management of open and coastal ocean in Sicily

2022 IEEE International Workshop on Metrology for the Sea; Learning to Measure Sea Health Parameters (MetroSea)

Frontiers in Marine Science

The hydrological and biogeochemical time series from 2010 to 2020 have highlighted specific relat... more The hydrological and biogeochemical time series from 2010 to 2020 have highlighted specific relationships and trends in oceanographic processes and nutrient patterns in the Sicily Channel. Specifically, temperature and salinity time series in the intermediate waters showed a sharp annual increase of about 0.06°C and 0.09 within the period 2010-2020, at rates that are about 50% higher than what observed within the previous decade. Similar trends were also present in deep waters, although with lower variations of both temperature and salinity. The time series in the intermediate water, also highlighted the presence of quasi cyclic fluctuations that can be associated with the alternation of the circulation modes (cyclonic and anticyclonic) of the Northern Ionian Gyre. Moreover, an opposite trend emerged by comparing the nutrients and salinity time series in intermediate waters, while similar patterns has been evidenced between nutrients and chlorophyll-a concentration. This latter find...

Stable isotopes, radionuclides, and calculated sea surface temperature of sediment core ANSIC-03_342

Relative abundances of calcareous nannofossil taxa in sediment core MD01-2444

Supplementary material to "Calcareous nannofossil assemblages from the Central Mediterranean Sea over the last four centuries: the impact of the little ice age

Table S2) Abundance of Florisphaera profunda in Silicy Channel surface sediments

Holocene millenial-scale productivity record in the Mediterranean Sea

The calcareous nannofossil assemblages of Ocean Drilling Program Hole 963D from the central Medit... more The calcareous nannofossil assemblages of Ocean Drilling Program Hole 963D from the central Mediterranean Sea have been investigated to document oceanographic changes in surface waters. The studied site is located in an area sensitive to large-scale atmospheric and climatic systems and to high- and low-latitude climate connection. It is characterized by a high sedimentation rate (the achieved mean sampling resolution is <70 years) that allowed the Sicily Channel environmental changes to be examined in great detail over the last 12 ka BP. We focused on the species Florisphaera profunda that lives in the lower photic zone. Its distribution pattern shows repeated abundance fluctuations of about 10-15%. Such variations could be related to different primary production levels, given that the study of the distribution of this species on the Sicily Channel seafloor demonstrates the significant correlation to productivity changes as provided by satellite imagery. Productivity variations were quantitatively estimated and were interpreted on the basis of the relocation of the nutricline within the photic zone, led by the dynamics of the summer thermocline. Productivity changes were compared with oceanographic, atmospheric, and cosmogenic nuclide proxies. The good match with Holocene master records, as with ice-rafted detritus in the subpolar North Atlantic, and the near-1500-year periodicity suggest that the Sicily Channel environment responded to worldwide climate anomalies. Enhanced Northern Hemisphere atmospheric circulation, which has been reported as one of the most important forcing mechanisms for Holocene coolings in previous Mediterranean studies, had a remarkable impact on the water column dynamics of the Sicily Channel.

Stable isotopes, radionuclides, and calculated sea surface temperature of two sediment cores in the Sicily Channel

The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the... more The Eastern Mediterranean Transient (EMT) occurred in the Aegean Sea from 1988 to 1995 and is the most significant intermediate-to-deep Mediterranean overturning perturbation reported by instrumental records. The EMT was likely caused by accumulation of high salinity waters in the Levantine and enhanced heat loss in the Aegean Sea, coupled with surface water freshening in the Sicily Channel. It is still unknown whether similar transients occurred in the past and, if so, what their forcing processes were. In this study, sediments from the Sicily Channel document surface water freshening (SCFR) at 1910±12, 1812±18, 1725±25 and 1580±30 CE. A regional ocean hindcast links SCFR to enhanced deep-water production and in turn to strengthened Mediterranean thermohaline circulation. Independent evidence collected in the Aegean Sea supports this reconstruction, showing that enhanced bottom water ventilation in the Eastern Mediterranean was associated with each SCFR event. Comparison between the records and multi-decadal atmospheric circulation patterns and climatic external forcings indicates that Mediterranean circulation destabilisation occurs during positive North Atlantic Oscillation (NAO) and negative Atlantic Multidecadal Oscillation (AMO) phases, reduced solar activity and strong tropical volcanic eruptions. They may have recurrently produced favourable deep-water formation conditions, both increasing salinity and reducing temperature on multi-decadal time scales.

(Table dS1) Abundance of Florisphaera profunda in ODP Hole 160-963D

(Table S1) Age determination of ODP Hole 160-963D

Absolute abundances of calcareous nannofossil taxa in sediment core MD01-2444

Environmental Science & Policy, 2019

The International Cooperation GVC-UCODEP project "Promotion of environmental protection in the Vi... more The International Cooperation GVC-UCODEP project "Promotion of environmental protection in the Việt Yên, Yên Dũng and Hiệp Hòa districts in the Bắc Giang Province, Vietnam" aimed at the restoration and preservation of natural resources together with the improvement of life conditions of the local population. It focused on the management of pollutant factors and ecological resources of the Bắc Giang Province. An important part of the project was devoted to the implementation of an institutional frame for monitoring the status of the environment, and within this frame a scientific survey was promoted in order to assess the degree of contamination from persistent organic pollutants in soils and sediments of selected areas of the Bắc Giang Province and the bordering Cầu River. The toxicological significance of measured concentrations, and the relative importance of pollutant sources were also investigated. At the same time, enforced Vietnamese regulations were studied to check their effectiveness in protecting the population and the environment. Results of this combined work provided a series of suggestions to central and local authorities in order to ensure people's health and a better monitoring of local natural resources. It is our hope that the described approach and methodology could inspire similar synergies between research and non-governmental institutions in other developing countries.

Benthic bio-indicators in a sensitive marine coastal area (Gulf of Palermo, Italy)

This work investigates a sensitive marine coastal area within the Gulf of Palermo, affected by th... more This work investigates a sensitive marine coastal area within the Gulf of Palermo, affected by the presence of the sewage treatment plant of the site “Acqua dei Corsari”, with an average daily carrying capacity of mc d-1 84.871, and by the proximity to an oil platform and the Palermo’s commercial and touristic harbour. Soft bottom benthic assemblages are particularly important because of their sensitivity to the variation of environmental conditions, both natural and anthropogenic, and especially benthic foraminiferal communities, as well as macrozoobenthos populations, are considered effective bio-indicators. Focus of this investigation is the analyses of living and dead communities of benthic foraminifera (assemblages, morphology, presence of tolerant species), the comparison of their response to the disturbance to that of associated macrozoobenthic assemblages (analyzed by AMBI and M-AMBI indices), as well as of chemical-physical characteristics of seawaters and sediments (pH, Eh...

The influence of microhabitat features on benthic foraminiferal distributions and biofacies along a depth transect of the Central-Southern Mediterranean Sea (Sicily, Italy)

The Mediterranean Sea is a mid-latitude semi-enclosed basin connected to the Atlantic Ocean and s... more The Mediterranean Sea is a mid-latitude semi-enclosed basin connected to the Atlantic Ocean and surrounded by the Mediterranean region. The investigation of the southern part of the Mediterranean Sea is of particular importance as it divides the Tyrrhenian Sea and the western Mediterranean Sea from the eastern Mediterranean, where different water masses are encountered. A total of twelve stations were sampled along a ca. 150 m bathymetric transect between the southern tip of Sicily and archipelago of Malta on July, 2013. Physico-chemical parameters of water and sediments were measured in vertical profile and three-replicated sediment samples were collected by box-corer. Total benthic foraminiferal assemblages were studied in order to identify the distribution and biofacies of the most abundant taxa and to relate them to the different water masses. Additionally, the microhabitats of live benthic foraminifera were documented by slicing the core at 0.5 cm intervals from 0 to 1 cm depth...

Fisheries Oceanography, 2015

In order to investigate the larval population structure, specimens of Engraulis encrasicolus larv... more In order to investigate the larval population structure, specimens of Engraulis encrasicolus larvae from five different locations in the Strait of Sicily were analyzed by means of otolith readings, morphometric and genetic techniques. The distribution of age in day, identified by means of the otolith readings and associated with the oceanographic parameters, was useful to identify possible spawning areas and transport dynamics. The presence of more than one spawning area suggested the possibility that two or more sub-populations may co-exist in the study area. The morphometric characteristics were more adequate than genetic parameters to discriminate the different larval groups. The most relevant variables for the separation were the mouth length (ML) and the body diameter (BD). The population structure by means of genetic data reported the presence of two phylogroups co-occurring among samples in each sampling locations specimens. The pattern of genetic divergence among anchovy larvae in the Strait of Sicily was congruent with previous studies conducted on adult populations present in other Mediterranean areas with different molecular markers. The habitat-specific nature of the morphological variation and the lack of corresponding genetic variation among larvae from the different locations suggested that the observed differences in morphology could be linked to environmental parameters. The body form differences among different larvae samples could reflect the nutritional status of larvae. In fact, these differences were found among anchovy larvae collected in areas with different oxygen and fluorescence, which is an index of primary productivity and is linked to the availability of food for anchovy larvae.

Studio delle tanatocenosi a foraminiferi bentonici nel Golfo di Gela

Sui campioni appena prelevati, sono stati misurati i valori di (pH, Eh e Temperatura) (Tab. 7a, b... more Sui campioni appena prelevati, sono stati misurati i valori di (pH, Eh e Temperatura) (Tab. 7a, b, c, d) (Fig. ) ed è stata effettuata una descrizione macroscopica consistente nella valutazione delle dimensioni granulometriche prevalenti per stima visiva e nella definizione del colore attraverso la comparazione con la "Munsell Rock Color Chart"(1975) 2009 Revision.

Sedimentary Geology, 2013

The Thetis basin is a deep hypersaline anoxic basin in the western part of the Mediterranean Ridg... more The Thetis basin is a deep hypersaline anoxic basin in the western part of the Mediterranean Ridge (eastern Mediterranean Sea). It is characterised by highly sulphidic NaCl-saturated brine with one of the highest values of salinity reported from similar basins (S ~348‰). The strong pycnocline at the seawater-brine interface induces permanent anoxic bottom conditions driving depositional processes and distribution patterns of redox-sensitive metals in the sediments. This work presents a high-resolution dataset of sedimentological, mineralogical and geochemical features and planktonic foraminifera distribution, derived from the exploration of a 52 cm long box-core sampled in the Thetis sediments. Basing on direct comparisons with available data from other hypersaline records and ancient anoxic organic-rich deep-sea records (sapropels and black shales), we aim to explore the potential of these anoxic basins as natural laboratories to better understand the mechanisms driving geochemical patterns in recent/ancient anoxic sediments.

Some consideration about the management and economic aspect on the pinger use for mitigation the depredation phenomena in an MPA Mediterranean area

The Journal of the Acoustical Society of America, 2011

This study was carried out in a fishing area off the coast of southern Italy, where Tursiops trun... more This study was carried out in a fishing area off the coast of southern Italy, where Tursiops truncatus is frequently observed to interact with bottom gill nets. The experiments aimed to assess the economic efficiency of the DDD pingers during the interaction between dolphins and monofilament bottom gill nets. A net was equipped with pingers and another without to measure the different biomass catch and costs. The economic effectiveness with an estimate of the costs/benefits was evaluated. We modeled a catch per unit effort (CPUE) both in economic terms as euros per 50 m of net set and in biomass terms as kilograms caught per 50 m of net set with and without pingers. The analysis of the data allowed us to evaluate the advantage of the economic aid provided by the European Fisheries Fund (EFF) for the use of pinger. The CPUE of the net equipped with pingers was statistically higher than the control net. The costs of investment for pingers could fully comeback in 74 days and with the e...