0000000000220059
AUTHOR
Walter D’alessandro
Soils as natural filters for GHG: an imbalance between the expected CH4 fluxes and the direct measurements
The final composition of the atmosphere results from several processes and exchanges between all the Earth’s spheres. Some of these are widely known and others, such as the methane degassing from hydrothermal areas, are still understudied. Methane plays a key role in climate change being an efficient greenhouse gas. Although it would be crucial, the total CH4 output from geogenic sources is still not well defined; limitations in CH4 output estimations are due to many factors concerning a scarce dataset availability, difficulty in direct measurements, and interaction with methane-consuming microbiota in the soil. Often, the CH4 flux estimation was obtained indirectly, e.g. cross-correlating …
Atmospheric Deposition around the Industrial Areas of Milazzo and Priolo Gargallo (Sicily–Italy)—Part A: Major Ions
The chemical composition of rainwater was studied in two highly-industrialised areas in Sicily (southern Italy), between June 2018 and July 2019. The study areas were characterised by large oil refining plants and other industrial hubs whose processes contribute to the release of large amounts of gaseous species that can affect the chemical composition of atmospheric deposition As in most of the Mediterranean area, rainwater acidity (ranging in the study area between 3.9 and 8.3) was buffered by the dissolution of abundant geogenic carbonate aerosol. In particular, calcium and magnesium cations showed the highest pH-neutralizing factor, with ~92% of the acidity brought by SO42− and NO…
Preliminary results of biomonitoring survey at Virunga Volcanic Province (D.R. Congo), Eastern Africa.
Biomonitoring techniques have been widely used in environmental studies to monitor anthropogenic pollutants. Recently such techniques have been also applied to ascertain the impact of contaminants naturally released by volcanic activity (Calabrese et al., 2015; Arndt et al., 2017). In the present study a biomonitoring survey has been performed in different sites around Nyiragongo and Nyamulagira (D.R. Congo), active volcanoes in the western branch of the East African Rift. We applied both active and passive biomonitoring techniques in order to investigate the release of some harmful chemical elements by Nyiragongo and Nyamulagira: the former was performed by exposing moss-bags (Sphagnum sp.…
¿Una nueva vertiente en el Volcán Copahue?: El caso del río Colorado.
El volcán Copahue (37°51′08″S–71°10′03″O) ha sido uno de los más estudiados del cinturón volcánico Argentino-Chileno, desarrollándose numerosos trabajos desde el punto de vista geoquímico, y en particular abarcando el estudio de las aguas del sistema. Dichos trabajos se concentran en su mayoría en las nacientes del sistema volcánico hidrotermal (SVH) (Agusto et al, 2012). Sin embargo, existen varios afluentes que alimentan al rio Caviahue de los cuales no se tiene mayor información. El objetivo de este trabajo es dterminar el origen de uno de ellos, el río Colorado. Desde el flanco E del volcán emanan dos vertientes ácidas (pH 1-2,5) y calientes (35-45°C) que se unen para formar el río Agri…
Shallow Sea Gas Manifestations in the Aegean Sea (Greece) as Natural Analogs to Study Ocean Acidification: First Catalog and Geochemical Characterization
The concepts of CO2 emission, global warming, climate change, and their environmental impacts are of utmost importance for the understanding and protection of the ecosystems. Among the natural sources of gases into the atmosphere, the contribution of geogenic sources plays a crucial role. However, while subaerial emissions are widely studied, submarine outgassing is not yet well understood. In this study, we review and catalog 122 literature and unpublished data of submarine emissions distributed in ten coastal areas of the Aegean Sea. This catalog includes descriptions of the degassing vents through in situ observations, their chemical and isotopic compositions, and flux estimations. Tempe…
Dissolved major and trace elements in meteoric depositions on the flanks of Mt. Etna (Italy): the impact of volcanic activity on the environment
In the framework of the “Save the Etna World” research project, which investigates the impact of the volcanic activity on the surrounding environment, three bulk collectors were deployed on the flank of the Mt. Etna volcano to collect the meteoric depositions. The sampling sites were at distances between 5.5 and 13 km from the summit vents of the volcano on its eastern flank, that is the most exposed to the volcanic plume due to the high-altitude prevailing winds direction. The sites were selected in order to have a gradient of exposition with respect to the volcanic emissions, the most exposed being CIT, the intermediate ILI and the least NIC. Samples were collected monthly from July 2017 …
Preliminary geochemical characterization of gas manifestations in North Macedonia
<p>Like most of the Balkan Peninsula, North Macedonia is a geodynamically active area. As such it has many hydrothermal features and gas manifestations. Until now, no systematic study about the geochemical characterization of the geogenic gases was made before in this country. In August 2019, 24 gas samples were collected in the study area. All, except one collected at Duvalo (soil gas), are gases bubbling or dissolved in thermomineral waters (temperatures from 12 to 66 °C). They were analysed in the laboratory for their chemical (He, Ne, Ar, O<sub>2</sub> , N<sub>2</sub> , H<sub>2</sub&…
Atmospheric Deposition around the Industrial Areas of Milazzo and Priolo Gargallo (Sicily–Italy)—Part B: Trace Elements
The concentrations of trace elements in atmospheric bulk depositions (wet plus dry) were investigated from two highly industrialised areas of Sicily (southern Italy) from June 2018 to July 2019, in order to recognise the main natural and anthropogenic sources. A side objective of this study was to improve the common sampling procedures and analytical methods used for monitoring trace elements in atmospheric deposition. The trace element VWM (Volume-Weighted Mean) concentrations ranged from less than 0.01 μg L−1 for trace elements such as Cs, Tl, and U, up to 24 μg L−1 for minor elements (Al, Zn, Sr), in the filtered aliquot, while they reached concentrations up to 144 μ…