Search results for "LCA"
showing 10 items of 1995 documents
Isotopic composition of single rain events in the central Mediterranean
2008
[1] The ratios of stable isotopes of single rain events were investigated during the period October 2005 to September 2006 in the central Mediterranean. Clear seasonal trends were identified in both oxygen isotope ratios and the deuterium-excess parameter, and these were ascribed to the dominant circulation systems during both cold and hot intraannual periods. Rain events were classified on the basis of the origin of rain-bearing systems. Air masses coming from the south usually give rise to rainwater with a low deuterium excess. Air masses coming from the north and the northeast are often dry and cold, and are associated with high evaporation from the Mediterranean Sea that occurs under is…
Chronological records of metal deposition in sediments from the Strait of Sicily, central Mediterranean: assessing natural fluxes and anthropogenic a…
2010
Abstract Sediment box-cores were recovered from the Strait of Sicily along two onshore–offshore transects in water depths of 29–500 m. Samples were dated by 210 Pb and analysed for major and trace elements. Inspections of chronological profiles integrated with application of statistical algorithms to the geochemical dataset and supported by in situ hydrological observations were used to assess factors driving element distributions. Mineralogical and chemical variability of sediments offshore of the southwestern Sicily coast reflect the irregular sea floor morphology of the Adventure Bank. Anthropogenic inputs explain enrichments with respect to background values for Sb, As, Pb, and Hg, that…
Calcareous Nannofossil and Planktonic Foraminifera Biostratigraphy of selected Piacenzian-Gelasian Laminites from Southern Italy
2011
Here we present the biostratigraphic and chronostratigraphic framework of a number of selected diatomaceous laminated intervals from the Crotone Basin (Calabria, Southern Italy). These layers, which we consider correlative to the Eastern Mediterranean Sapropel Layers, range in age from the early Piacenzian to the Gelasian, and show surprising thicknesses, suggesting that they were probably laid down in a landlocked, overfed basin. Specifically, a thick laminite from the surroundings of Cropani (Catanzaro) can be ascribed to nannofossil biozone MNN 16a and planktonic foraminifera biozone MPL 4b (lower Piacenzian) according to the Mediterranean calcareous plankton biostratigraphic zonations. …
Pedogenic carbonates and carbon pools in gypsiferous soils of a semiarid Mediterranean environment in south Italy
2013
Abstract Soil carbonates are key features in soils of arid and semiarid environment, playing an important role from pedogenetic, landscape history, paleoclimatic and environmental points of view. The objectives of this work were (i) to study pathways of pedogenic carbonate (PC) formation, (ii) to distinguish between lithogenic and pedogenic inorganic C by using the natural C isotope abundance, and (iii) to estimate the soil C pools in a gypsiferous semiarid Mediterranean environment (Sicily, Italy). Five soil pedons developed on calcareous and non-calcareous parent materials from Holocene (10,000 years BP) to Upper Tortonian (7.2–5.3 Ma BP) in age were surveyed. During field soil descriptio…
Spatial and temporal variations of water repellency and probability of its occurrence in calcareous Mediterranean rangeland soils affected by fires
2013
Abstract Water repellency (WR) is a common soil property in many fire-affected ecosystems, but it also occurs in long-unburned terrain. It can vary in space at different scales (between point and pedon or slope and catchment) and time (during the same day, between seasons or years, or with a post-fire recovery period). This paper: i) reports on the occurrence and persistence of WR in fire-affected calcareous forest soils under Mediterranean climatic conditions, examining its spatial variability at macro-, meso- and micro-scales, and monthly changes with soil moisture content; and ii) develops exploratory models to estimate the probability of the natural background (not fire-induced) WR to o…
Natural and anthropogenic sources of total suspended particulate and their contribution to the formation of black crusts on building stone materials …
2012
Blackening and disaggregation of exposed surfaces of stone monuments are well-known effects of stone decay taking place in polluted urban environments all over the world. This paper aims to assess the contribution of natural and anthropogenic sources of total suspended particulate (TSP) causing permanent damage (black crusts) to the stone monuments of Catania (Sicily), one of the most popular ‘‘cities of art’’ of southern Italy. Atmospheric pollution of Catania, a typical Mediterranean coastal town, is mainly contributed by vehicle exhaust emissions rather than industrial ones. Episodically, the city also suffers gaseous and ash emissions (plumes) from the nearby Mount Etna volcano. Thus, t…
Sea level and climate forcing of the Sr isotope composition of late Miocene Mediterranean marine basins
2014
Sr isotope records from marginal marine basins track the mixing between seawater and local continental runoff, potentially recording the effects of sea level, tectonic, and climate forcing in marine fossils and sediments. Our 110 new Sr-87/Sr-86 analyses on oyster and foraminifera samples from six late Miocene stratigraphic sections in southern Turkey, Crete, and Sicily show that Sr-87/Sr-86 fell below global seawater values in the basins several million years before the Messinian Salinity Crisis, coinciding with tectonic uplift and basin shallowing. 87Sr/86Sr from more centrally located basins (away from the Mediterranean coast) drop below global seawater values only during the Messinian S…
The growth of “black crusts” on calcareous building stones in Palermo (Sicily): a first appraisal of anthropogenic and natural sulphur sources
2008
Chemical, mineralogical and isotopic composition (34S/32S) analyses were carried out on “black crusts” developed on the old buildings of Palermo (Sicily) with the aim to distinguish between natural and anthropogenic sulphur sources. Furthermore individual samples of total suspended particulate (TSP) were collected and analysed in order to estimate the influence of air pollution on the decay process of calcareous stones in a typical southern Mediterranean coastal environment. SEM/EDS analysis, X-ray diffractometry, IR spectroscopy and liquid chromatography led to the compositional characterization of “black crusts” and airborne particulate matter in the city. Sulphur isotopic compositions of…
Bioindication of volcanic mercury (Hg) deposition around Mt. Etna (Sicily)
2012
Mt. Etna is a major natural source of Hg to the Mediterranean region. Total mercury concentrations, [Hg] tot, in Castanea sativa (sweet chestnut) leaves sampled 7-13km from Etna's vents (during six campaigns in 2005-2011) were determined using atomic absorption spectroscopy. [Hg] tot in C. sativa was greatest on Etna's SE flank reflecting Hg deposition from the typically overhead volcanic plume. [Hg] tot also showed Hg accumulation over the growing season, increasing with leaf age and recent eruptive activity. [Hg] tot in C. sativa was not controlled by [Hg] tot in soils, which instead was greatest on Etna's NW flank, and was correlated with the proportion of organic matter in the soil (% O…
Calcareous nannofossil surface sediment assemblages from the SicilyChannel (central Mediterranean Sea): palaeoceanographic implications.
2008
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…