Search results for "Trace element"

Multi-isotopic and trace element evidence against different formation pathways for oyster microstructures

2021

Geochimica et cosmochimica acta 308, 326-352 (2021). doi:10.1016/j.gca.2021.06.012

FIRST APPLICATION OF ACTIVE BIOMONITORING TECHNIQUES (MOSS-BAGS) TO MAP THE DISPERSION OF VOLCANIC EMISSIONS

2011

Biomonitoring may be defined as the use of organisms and biomaterials (biomonitors) to obtain informations on certain characteristics of a particular medium (atmosphere, hydrosphere etc.). In particular, mosses accumulate large amounts of trace metals, making them good bioaccumulators to estimate atmospheric pollution. The moss-bags technique, introduced in the early 1970’, has become very popular. Such active biomonitoring technique is particularly useful in highly polluted areas and has been extensively used in industrial and/or urban areas to examine deposition patterns and to recognize point sources of pollution. The main objective of this study, which represents the first application o…

Trace Elements in Soils and Plants from the Active Hydrothermal Area of Nisyros (Greece)

2014

Plants as biomonitors for volcanic emissions

2014

Biomonitoring techniques have been widely used in environmental studies to monitor anthropogenic pollutant. Recently such techniques have been applied also to ascertain the impact of contaminants naturally released by volcanic activity. In the present study a biomonitoring surveys has been performed in many different active volcanic systems: Mt. Etna and Vulcano (Italy), Nisyros (Greece), Nyiragongo (DRC), Masaya (Nicaragua), Gorely (Kamchatka, Russia). We sampled leaves of different species Betulla aethnensis, Pinus nigra, Populus tremula, Senecio aethnensis and Rumex aethnensis on Etna, Cistus creticus and salvifolius on Vulcano and Nisyros, Senecio ssp. on Nyiragongo, a Fern on Masaya an…

Microbial acidification and pH effects on trace element release from sewage sludge.

2003

Leaching of sludge-borne trace elements has been observed in experimental and field studies. The role of microbial processes in the mobilization of trace elements from wastewater sludge is poorly defined. Our objectives were to determine trace element mobilization from sludge subjected to treatments representing microbial acidification, direct chemical acidification and no acidification, and to determine the readsorption potential of mobilized elements using calcareous sand. Triplicate columns (10-cm diameter) for incubation and leaching of sludge had a top layer of digested dewatered sludge (either untreated, acidified with H2SO4, or limed with CaCO3; all mixed with glass beads to prevent …

Impact of trace metals from past mining on the aquatic ecosystem: a multi-proxy approach in the Morvan (France).

2014

10 pages; International audience; This study seeks to determine to what extent trace metals resulting from past mining activities are transferred to the aquatic ecosystem, and whether such trace metals still exert deleterious effects on biota. Concentrations of Cd, Cu, Pb and Zn were measured in streambed sediments, transplanted bryophytes and wild brown trout. This study was conducted at two scales: (i) the entire Morvan Regional Nature Park and (ii) three small watersheds selected for their degree of contamination, based on the presence or absence of past mining sites. The overall quality of streambed sediments was assessed using Sediment Quality Indices (SQIs). According to these standar…

Evaluation of saltwork ponds operation through brine characterization and geochemical modelling using PHREEQC code integrating the Pitzer correction

2021

Seawater represents a potential resource for the extraction of salts and raw materials [1]. About one-third of the global table-salt production is manufactured in solar saltworks [2], being the most representative product of seawater processing. However, other valuable compounds such as Magnesium, Lithium and trace elements belonging to the alkaline/alkaline-earth metals (e.g. Rb, Cs, Sr) and transition/post-transition metals (e.g. Co, Ga, Ge) are present. Many of these elements are included in the EU Critical Raw Materials (CRM) list, grouping natural assets classified as fundamental for the wealth of the socio-economic structure of Europe [3]. In saltworks, natural evaporation of seawater…

Bulk deposition at the industrial area of Gela (southern Sicily, Italy): preliminary results

2009

Carbonate deposits from the ancient aqueduct of Béziers, France — A high-resolution palaeoenvironmental archive for the Roman Empire

2016

Abstract Carbonate deposits from a Roman aqueduct in Beziers, southern France, record environmental conditions during the late first century C.E. These deposits formed in a steep section of the aqueduct with a high flow velocity, which caused rapid deposition of up to 11 mm of calcite per year over a period of 22–24 years. The microstructure, trace element and stable isotope composition show that regular deposition was interrupted by high-discharge events, probably in response to heavy rainfall during autumn and winter, transporting colloidally- and particle-bound elements and depositing calcite with elevated δ 18 O values. Individual autumn high-discharge events coincide with abrupt decrea…

High-resolution analysis of trace elements in crustose coralline algae from the North Atlantic and North Pacific by laser ablation ICP-MS

2011

We have investigated the trace elemental composition in the skeleta of two specimens of attached-living coralline algae of the species Clathromorphum compactum from the North Atlantic (Newfoundland) and Clathromorphum nereostratum from the North Pacific/Bering Sea region (Amchitka Island, Aleutians). Samples were analyzed using Laser Ablation-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) yielding for the first time continuous individual trace elemental records of up to 69 years in length. The resulting algal Mg/Ca, Sr/Ca, U/Ca, and Ba/Ca ratios are reproducible within individual sample specimens. Algal Mg/Ca ratios were additionally validated by electron microprobe analyses (Amch…