0000000000220340
AUTHOR
F. Placenti
The behaviour of REEs in Thailand's Mae Klong estuary: Suggestions from the Y/Ho ratios and lanthanide tetrad effects
Abstract The concentrations of Rare Earth Elements and yttrium (REY) were measured in dissolved phase, in suspended particulate matter (SPM) and in sediments in seven sampling stations in the Mae Klong estuarine system (Inner Thailand Gulf) in order to study their behaviour and distribution pattern. The analysed samples generally show high Rare Earth Element (REE) content in the dissolved phase, with high Medium Rare Earth Elements (MREEs) and Y enrichments in the shale-normalized pattern (versus PAAS). These chemical features are interpreted in terms of direct influences of weathering processes of REE-rich minerals (e.g., phosphates), which abundantly out-crop in the Mae Klong watershed. T…
La sostenibilità delle destinazioni turistiche: la misurazione per indicatori
Tourism often has had (and has) detrimental outcomes on destinations but the need and the rele-vance of a sustainable development of tourism was only recently recognised. Sustainable tour-ism is a quite recent concept, derived by the notion of sustainable development; it is usually re-lated to environmental issues and particularly to natural resources waste. Wider definitions are now emerging in the scientific community including, usually, social and economic dimensions together with the environmental one. Although, the intrinsic multidimensional nature of sustain-ability and the high number of stakeholders to be involved in its evaluation (e.g. policy makers, administrators, local resident…
Calcareous nannofossil surface sediment assemblages from the SicilyChannel (central Mediterranean Sea): palaeoceanographic implications.
Quantitative analysis of 67 calcareous nannofossil assemblages from surface sediments recovered in a wide area across the Sicily Channel has been carried out in order to improve the interpretation of palaeontological data based on this planktonic group in a key area for Mediterranean palaeoceanographic studies. The investigation focused on three case studies that demonstrate the high potentiality of such a combined approach, taking into account the recent distribution of taxa or groups of taxa on the sea floor and the palaeontological record. The distribution of reworked specimens over the northern Sicily Channel sea floor validates the role of southern Sicily as a source region for reworke…
Long-term analysis (1863–2002) of environmental change in the Capo Feto area (Mediterranean sea)
The area of Capo Feto represents one of the few remaining salt-marshy zones in Sicily. It lies within a site of importance for the Community (defined as a “sito di importanza comunitaria” (SIC)), which also includes Margi Spanò and Margi Milo. The Capo Feto and Margi Spanò marshlands have also been identified by the Ministry for the Environment as an area deserving special protection (“zona a protezione speciale” (ZPS)). Moreover, in 1999, 150 ha of the Capo Feto area were included in a project for environmental rehabilitation as part of the European Union “Life-Nature 2000” programme (Comitato Tecnico-Scientifico Area di Capo Feto, 1997). Prior to this, the area had become somewhat degrade…
Morpho-sedimentary setting and evolution of Marettimo Valley (Egadi Islands, Sicily) during middle-late Quaternary: interaction between sea level changes and oceanographic circulation
We present morphological and stratigraphic results coming from surveys acquired in a NNW-SSE trending submarine depression (Marettimo Valley) located in the Egadi Islands (western Sicily offshore). In this area the seafloor is characterized by both depositional and erosional features generated under a variety of sedimentary processes. We identified two seismic facies units that are correlatable to: A) the progradation of shallow water (coastal to offshore) deposits during forced-regression sedimentary process, and B) contourite drifts emplaced by geostrophic currents through the Marettimo Valley. This unusual association of very shallow water contourites and shelf margin deposits originates…
Recognition of water masses according to geochemical signatures in the Central Mediterranean sea: Y/Ho ratio and rare earth element behaviour
This study reports the results of geochemical investigations carried out in the Strait of Sicily (Central Mediterranean Sea) during the oceanographic cruise BANSIC 2000, focusing on the area around the Pantelleria Island. We evaluate the interface processes between dissolved phase and suspended particulate matter in the water columns on the basis of Y/Ho ratio and rare earth elements and yttrium distributions that are suitable to trace the occurrence of different water layers in Central Mediterranean Area. The main source of trace elements to the sea water system was recognized in the atmospheric fallout, while different scavenging mechanisms among Y and rare earth elements occur. Cation ex…