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https://www.readbyqxmd.com/read/29122367/stabilization-of-arsenic-and-lead-by-magnesium-oxide-mgo-in-different-seawater-concentrations
#1
Kentaro Kameda, Yohey Hashimoto, Yong Sik Ok
Ongoing sea level rise will have a major impact on mobility and migration of contaminants by changing a number of natural phenomena that alter geochemistry and hydrology of subsurface environment. In-situ immobilization techniques may be a promising remediation strategy for mitigating contaminant mobility induced by sea level rise. This study investigated the reaction mechanisms of magnesium oxide (MgO) with aqueous Pb and As under freshwater and seawater using XAFS spectroscopy. Initial concentrations of Pb and As in freshwater strongly controlled the characteristics of the reaction product of MgO...
November 6, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/29112922/statistical-comparison-of-leaching-behavior-of-incineration-bottom-ash-using-seawater-and-deionized-water-significant-findings-based-on-several-leaching-methods
#2
Ke Yin, Xiaomin Dou, Fei Ren, Wei-Ping Chan, Victor Wei-Chung Chang
Bottom ashes generated from municipal solid waste incineration have gained increasing popularity as alternative construction materials, however, they contains elevated heavy metals posing a challenge for its free usage. Different leaching methods are developed to quantify leaching potential of incineration bottom ashes meanwhile guide its environmentally friendly application. Yet, there are diverse IBA applications while the in situ environment is always complicated, challenging its legislation. In this study, leaching tests were conveyed using batch and column leaching methods with seawater as opposed to deionized water, to unveil the metal leaching potential of IBA subjected to salty environment, which is commonly encountered when using IBA in land reclamation yet not well understood...
November 2, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/29111252/organic-matter-control-on-the-distribution-of-arsenic-in-lake-sediments-impacted-by-65years-of-gold-ore-processing-in-subarctic-canada
#3
Jennifer M Galloway, Graeme T Swindles, Heather E Jamieson, Michael Palmer, Michael B Parsons, Hamed Sanei, Andrew L Macumber, R Timothy Patterson, Hendrik Falck
Climate change is profoundly affecting seasonality, biological productivity, and hydrology in high northern latitudes. In sensitive subarctic environments exploitation of mineral resources led to contamination and it is not known how cumulative effects of resource extraction and climate warming will impact ecosystems. Gold mines near Yellowknife, Northwest Territories, subarctic Canada, operated from 1938 to 2004 and released >20,000t of arsenic trioxide (As2O3) to the environment through stack emissions...
October 27, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29103647/role-of-microbial-activity-in-fe-iii-hydroxysulfate-mineral-transformations-in-an-acid-mine-drainage-impacted-site-from-the-dabaoshan-mine
#4
Yanping Bao, Chuling Guo, Guining Lu, Xiaoyun Yi, Han Wang, Zhi Dang
Fe(III) hydroxysulfate minerals are secondary minerals commonly found in acid mine drainage (AMD) sites and have a major impact on water and soil quality in these environments. While previous studies showed that the Fe(III) hydroxysulfate mineral transformation could be mediated by some bacterial strains under laboratory conditions, the role of indigenous microbial activity in Fe(III) hydroxysulfate mineral transformation in natural environment has received little attention. In this study, microcosms were constructed with AMD-affected river water and sediment from the Dabaoshan Mine that was either left unamended or enriched with nutrients (lactate, nitrogen, and phosphorus (LNP)) and biosynthetic minerals (schwertmannite or jarosite)...
November 2, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29097678/planktic-foraminifera-form-their-shells-via-metastable-carbonate-phases
#5
D E Jacob, R Wirth, O B A Agbaje, O Branson, S M Eggins
The calcium carbonate shells of planktic foraminifera provide our most valuable geochemical archive of ocean surface conditions and climate spanning the last 100 million years, and play an important role in the ocean carbon cycle. These shells are preserved in marine sediments as calcite, the stable polymorph of calcium carbonate. Here, we show that shells of living planktic foraminifers Orbulina universa and Neogloboquadrina dutertrei originally form from the unstable calcium carbonate polymorph vaterite, implying a non-classical crystallisation pathway involving metastable phases that transform ultimately to calcite...
November 2, 2017: Nature Communications
https://www.readbyqxmd.com/read/29079745/learning-from-soil-gas-change-and-isotopic-signatures-during-2012-emilia-seismic-sequence
#6
Alessandra Sciarra, Barbara Cantucci, Massimo Coltorti
Soil surveys were performed in Medolla (Italy), a peculiar area characterized by spotty high soil temperature, gas vent, and lack of vegetation, to determine the migration mechanisms and spatial behavior of gas species. Hereby we present soil gas measurements and their isotopic ratios measured between 2008 and 2015, including the 2012 Emilia-Romagna seismic sequence. We found that soil gas concentrations markedly changed during the main shocks of May 20 and 29, 2012 (Mw 6.1 and 6.0, respectively), highlighting the presence of a buried fault intersecting the gas vents...
October 27, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29046572/nutrient-dependent-growth-underpinned-the-ediacaran-transition-to-large-body-size
#7
Jennifer F Hoyal Cuthill, Simon Conway Morris
Macroscale rangeomorph fossils, with characteristic branching fronds, appear (571 Myr ago) after the Gaskiers glaciation (580 Myr ago). However, biological mechanisms of size growth and potential connections to ocean geochemistry were untested. Using micro-computerized tomography and photographic measurements, alongside mathematical and computer models, we demonstrate that growth of rangeomorph branch internodes declined as their relative surface area decreased. This suggests that frond size and shape were directly responsive to nutrient uptake...
August 2017: Nature ecology & evolution
https://www.readbyqxmd.com/read/29043797/metal-oxides-in-surface-sediment-control-nickel-bioavailability-to-benthic-macroinvertebrates
#8
Raissa M Mendonca, Jennifer M Daley, Michelle L Hudson, Christian E Schlekat, G Allen Burton, David M Costello
In aquatic ecosystems, the cycling and toxicity of nickel (Ni) are coupled to other elemental cycles that can limit its bioavailability. Current sediment risk assessment approaches consider acid-volatile sulfide (AVS) as the major binding phase for Ni, but have not yet incorporated ligands that are present in oxic sediments. Our study aimed to assess how metal oxides play a role in Ni bioavailability in surficial sediments exposed to effluent from two mine sites. We coupled spatially explicit sediment geochemistry (i...
October 30, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/29042108/spatial-distribution-and-environmental-geochemistry-of-zinc-metal-in-water-and-surficial-bottom-sediments-of-lagoon-burullus-egypt
#9
Abd El-Monsef Ahmed El-Badry, Ahmad Mohamed El-Kammar
Lagoon Burullus is located in the North West quadrant of the Nile Delta. It receives drainage water through several drains around the lagoon. Understanding the mobility and bioavailability of zinc metal in bottom sediments of Lagoon Burullus is essential for the design of remediation processes and the institution of environmental recommendation for zinc pollution. Single extractions used to fractionate zinc into five fractions. The chemical analyses preceded using atomic absorption spectrometry after using the digestion technique...
October 14, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/29039682/on-the-habitability-of-desert-varnish-a-combined-study-by-micro-raman-spectroscopy-x-ray-diffraction-and-methylated-pyrolysis-gas-chromatography-mass-spectrometry
#10
C Malherbe, I B Hutchinson, R Ingley, A Boom, A S Carr, H Edwards, B Vertruyen, B Gilbert, G Eppe
In 2020, the ESA ExoMars and NASA Mars 2020 missions will be launched to Mars to search for evidence of past and present life. In preparation for these missions, terrestrial analog samples of rock formations on Mars are studied in detail in order to optimize the scientific information that the analytical instrumentation will return. Desert varnishes are thin mineral coatings found on rocks in arid and semi-arid environments on Earth that are recognized as analog samples. During the formation of desert varnishes (which takes many hundreds of years), organic matter is incorporated, and microorganisms may also play an active role in the formation process...
November 2017: Astrobiology
https://www.readbyqxmd.com/read/29038984/perturbation-vectors-to-evaluate-air-quality-using-lichens-and-bromeliads-a-brazilian-case-study
#11
F Monna, A N Marques, R Guillon, R Losno, S Couette, N Navarro, G Dongarra, E Tamburo, D Varrica, C Chateau, F O Nepomuceno
Samples of one lichen species, Parmotrema crinitum, and one bromeliad species, Tillandsia usneoides, were collected in the state of Rio de Janeiro, Brazil, at four sites differently affected by anthropogenic pollution. The concentrations of aluminum, cadmium, copper, iron, lanthanum, lead, sulfur, titanium, zinc, and zirconium were determined by inductively coupled plasma-atomic emission spectroscopy. The environmental diagnosis was established by examining compositional changes via perturbation vectors, an underused family of methods designed to circumvent the problem of closure in any compositional dataset...
October 17, 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/29035265/hydrothermal-impacts-on-trace-element-and-isotope-ocean-biogeochemistry
#12
C R German, K A Casciotti, J-C Dutay, L E Heimbürger, W J Jenkins, C I Measures, R A Mills, H Obata, R Schlitzer, A Tagliabue, D R Turner, H Whitby
Hydrothermal activity occurs in all ocean basins, releasing high concentrations of key trace elements and isotopes (TEIs) into the oceans. Importantly, the calculated rate of entrainment of the entire ocean volume through turbulently mixing buoyant hydrothermal plumes is so vigorous as to be comparable to that of deep-ocean thermohaline circulation. Consequently, biogeochemical processes active within deep-ocean hydrothermal plumes have long been known to have the potential to impact global-scale biogeochemical cycles...
November 28, 2016: Philosophical Transactions. Series A, Mathematical, Physical, and Engineering Sciences
https://www.readbyqxmd.com/read/29027362/impact-of-extraction-methods-on-the-detectable-protein-complement-of-metaproteomic-analyses-of-marine-sediments
#13
Lars Wöhlbrand, Christoph Feenders, Jessica Nachbaur, Holger Freund, Bert Engelen, Heinz Wilkes, Hans-Jürgen Brumsack, Ralf Rabus
Metaproteomic analysis targets proteins, the catalytic entities in the habitat, thereby providing direct insights into the metabolic activity of the community studied. A major challenge still remaining for metaproteomics is the effective and comprehensive extraction of proteins from environmental samples, due to their high complexity with respect to organismic diversity and abundance range. Moreover, in certain habitats, the inherent matrix may interfere with protein extraction. In recent years, several studies reported different protein extraction methods for soils known for their complex geochemistry, but only two analyzed marine sediments that generally comprise different though similarly complex geochemistry...
October 13, 2017: Proteomics
https://www.readbyqxmd.com/read/29027292/sr-isotope-measurement-of-basaltic-glasses-by-la-mc-icp-ms-based-on-a-linear-relationship-between-analytical-bias-and-rb-sr-ratios
#14
Le Zhang, Zhong-Yuan Ren, Ya-Dong Wu, Nan Li
RATIONALE: In-situ Sr isotope analysis of geological samples by laser ablation multiple collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) provides useful information about magma mixing, crustal contamination and crystal residence time. Without chemical separation, during Sr isotope analysis with laser ablation, many kinds of interference ions (such as Rb(+) and Kr(+) ) are on the Sr isotope spectrum. Most previous in-situ Sr isotope studies only focused on Sr-enriched minerals (e...
October 13, 2017: Rapid Communications in Mass Spectrometry: RCM
https://www.readbyqxmd.com/read/29027052/geochemical-fingerprints-of-prosecco-wine-based-on-major-and-trace-elements
#15
Salvatore Pepi, Carmela Vaccaro
The terroir can be defined as interactive ecosystem that includes climate, geology, soil and grapevine, and it is used to explain the hierarchy of high quality of wine. In order to understand the terroir functions, it is necessary to analyse the interactions among the geology, soil and wine. To define a geochemical fingerprint, the relationship between geochemistry of vineyard soil and chemical composition of wine from Veneto Italian Region was studied. The vineyards tested belonged to four distinct wineries located in the Veneto alluvial plain, included in the Controlled Designation of Origin (DOC) area of Prosecco...
October 12, 2017: Environmental Geochemistry and Health
https://www.readbyqxmd.com/read/29021556/unexpected-3-valence-of-iron-in-feo2-a-geologically-important-material-lying-in-between-oxides-and-peroxides
#16
Sergey S Streltsov, Alexey O Shorikov, Sergey L Skornyakov, Alexander I Poteryaev, Daniel I Khomskii
Recent discovery of the pyrite FeO2, which can be an important ingredient of the Earth's lower mantle and which in particular may serve as an extra source of water in the Earth's interior, opens new perspectives for geophysics and geochemistry, but this is also an extremely interesting material from physical point of view. We found that in contrast to naive expectations Fe is nearly 3+ in this material, which strongly affects its magnetic properties and makes it qualitatively different from well known sulfide analogue - FeS2...
October 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29019413/instrumentation-for-testing-whether-the-icy-moons-of-the-gas-and-ice-giants-are-inhabited
#17
Julian Chela-Flores
Evidence of life beyond Earth may be closer than we think, given that the forthcoming missions to the Jovian system will be equipped with instruments capable of probing Europa's icy surface for possible biosignatures, including chemical biomarkers, despite the strong radiation environment. Geochemical biomarkers may also exist beyond Europa on icy moons of the gas giants. Sulfur is proposed as a reliable geochemical biomarker for approved and forthcoming missions to the outer solar system. Key Words: JUICE mission-Clipper mission-Geochemical biomarkers-Europa-Moons of the ice giants-Geochemistry-Mass spectrometry...
October 11, 2017: Astrobiology
https://www.readbyqxmd.com/read/28989190/the-effect-of-ph-electrolytes-and-temperature-on-the-rhizosphere-geochemistry-of-phytosiderophores
#18
M Walter, S M Kraemer, W D C Schenkeveld
BACKGROUND AND AIMS: Graminaceous plants are grown worldwide as staple crops under a variety of climatic and soil conditions. They release phytosiderophores for Fe acquisition (Strategy II). Aim of the present study was to uncover how the rhizosphere pH, background electrolyte and temperature affect the mobilization of Fe and other metals from soil by phytosiderophores. METHODS: For this purpose a series of kinetic batch interaction experiments with the phytosiderophore 2'-deoxymugineic acid (DMA), a calcareous clay soil and a mildly acidic sandy soil were performed...
2017: Plant and Soil
https://www.readbyqxmd.com/read/28983105/transfer-of-marine-mercury-to-mountain-lakes
#19
Sophia V Hansson, Jeroen Sonke, Didier Galop, Gilles Bareille, Séverine Jean, Gaël Le Roux
Stocking is a worldwide activity on geographical and historical scales. The rate of non-native fish introductions have more than doubled over the last decades yet the effect on natural ecosystems, in the scope of biologically mediated transport and biomagnification of Hg and Hg-isotopes, is unknown. Using geochemistry (THg) and stable isotopes (N, Sr and Hg), we evaluate natal origin and trophic position of brown trout (Salmo trutta fario), as well as mercury biomagnification trends and potential pollution sources to three high-altitude lakes...
October 5, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28980802/naturally-occurring-versus-anthropogenic-sources-of-elevated-molybdenum-in-groundwater-evidence-for-geogenic-contamination-from-southeast-wisconsin-united-states
#20
Jennifer S Harkness, Thomas H Darrah, Myles T Moore, Colin J Whyte, Paul D Mathewson, Tyson Cook, Avner Vengosh
Molybdenum (Mo) is an essential trace nutrient but has negative health effects at high concentrations. Groundwater typically has low Mo (<2 μg/L), and elevated levels are associated with anthropogenic contamination, although geogenic sources have also been reported. Coal combustion residues (CCRs) are enriched in Mo, and thus present a potential anthropogenic contamination source. Here, we use diagnostic geochemical tracers combined with groundwater residence time indicators to investigate the sources of Mo in drinking-water wells from shallow aquifers in a region of widespread CCR disposal in southeastern Wisconsin...
November 7, 2017: Environmental Science & Technology
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