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https://www.readbyqxmd.com/read/28442237/long-term-ert-monitoring-of-biogeochemical-changes-of-an-aged-hydrocarbon-contamination
#1
David Caterina, Adrian Flores Orozco, Frédéric Nguyen
Adequate management of contaminated sites requires information with improved spatio-temporal resolution, in particular to assess bio-geochemical processes, such as the transformation and degradation of contaminants, precipitation of minerals or changes in groundwater geochemistry occurring during and after remediation procedures. Electrical Resistivity Tomography (ERT), a geophysical method sensitive to pore-fluid and pore-geometry properties, permits to gain quasi-continuous information about subsurface properties in real-time and has been consequently widely used for the characterization of hydrocarbon-impacted sediments...
April 10, 2017: Journal of Contaminant Hydrology
https://www.readbyqxmd.com/read/28437740/stabilization-of-metal-loid-s-in-two-contaminated-agricultural-soils-comparing-biochar-to-its-non-pyrolysed-source-material
#2
Lukáš Trakal, Irene Raya-Moreno, Kerry Mitchell, Luke Beesley
Two metal(loid) contaminated agricultural soils were amended with grape stalk (wine production by-product)-derived biochar as well as its pre-pyrolysed origin material, to investigate their geochemical impacts on As, Cr, Cu and Zn. Detailed physico-chemical evaluation combined with a column leaching test determined the retention of metal(loid)s from soil solution by each amendments. A pot experiment measured metal(loid)s in soil pore water and their uptake to ryegrass when the amendments were mixed into soils at 1 and 5% (w/w)...
April 15, 2017: Chemosphere
https://www.readbyqxmd.com/read/28434667/sedimentary-heavy-metal-loid-contamination-in-the-veracruz-shelf-gulf-of-mexico-a-baseline-survey-from-a-rapidly-developing-tropical-coast
#3
Celis-Hernandez Omar, Rosales-Hoz Leticia, Cundy Andrew B, Carranza-Edwards Arturo
This study examines sediment texture, geochemistry and sediment accumulation in cores from four sites in the Veracruz shelf area of the Gulf of Mexico, to assess the inputs of heavy metal(loid)s (and their potential biological impacts) in this carbonate-dominated shelf system, and to examine the rate of sedimentation near to the mouths of the La Antigua and Jamapa Rivers. The use of different pollution indices showed enrichment with Pb in all cores studied, although based on sediment quality guidelines As was the only element that has potential to occasionally cause damage to the benthic organisms present in the area...
April 20, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28418774/arsenic-in-the-groundwater-occurrence-toxicological-activities-and-remedies
#4
S K Jha, V K Mishra, T Damodaran, D K Sharma, Parveen Kumar
Arsenic (As) contamination in groundwater has become a geo-environmental as well as a toxicological problem across the globe affecting more than 100-million people in nearly 21 countries with its associated disease "arsenicosis." Arsenic poisoning may lead to fatal skin and internal cancers. In present review, an attempt has been made to generate awareness among the readers about various sources of occurrence of arsenic, its geochemistry and speciation, mobilization, metabolism, genotoxicity, and toxicological exposure on humans...
February 22, 2017: Journal of Environmental Science and Health. Part C, Environmental Carcinogenesis & Ecotoxicology Reviews
https://www.readbyqxmd.com/read/28417168/rdx-degradation-in-bioaugmented-model-aquifer-columns-under-aerobic-and-low-oxygen-conditions
#5
Mark E Fuller, Paul B Hatzinger, Charles W Condee, Christina Andaya, Rachel Rezes, Mandy M Michalsen, Fiona H Crocker, Karl J Indest, Carina M Jung, G Alon Blakeney, Jonathan D Istok, Steven A Hammett
Degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in laboratory columns following biostimulation and bioaugmentation was investigated using sediment and groundwater from a contaminated aquifer at a US Navy facility. No RDX degradation was observed following aerobic biostimulation with either fructose or lactate (both 0.1 mM) prior to bioaugmentation. Replicate columns were then bioaugmented with either Gordonia sp. KTR9, Pseudomonas fluorescens I-C (Ps I-C), or both strains. Under aerobic conditions (influent dissolved oxygen (DO) >6 mg/L), RDX was degraded following the addition of fructose, and to a lesser extent with lactate, in columns bioaugmented with KTR9...
April 17, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28399822/dominant-bacterial-phyla-in-caves-and-their-predicted-functional-roles-in-c-and-n-cycle
#6
Surajit De Mandal, Raghunath Chatterjee, Nachimuthu Senthil Kumar
BACKGROUND: Bacteria present in cave often survive by modifying their metabolic pathway or other mechanism. Understanding these adopted bacteria and their survival strategy inside the cave is an important aspect of microbial ecology. Present study focuses on the bacterial community and geochemistry in five caves of Mizoram, Northeast India. The objective of this study was to explore the taxonomic composition and presumed functional diversity of cave sediment metagenomes using paired end Illumina sequencing using V3 region of 16S rRNA gene and bioinformatics pipeline...
April 11, 2017: BMC Microbiology
https://www.readbyqxmd.com/read/28397387/a-geochemical-study-of-the-ediacaran-discoidal-fossil-aspidella-preserved-in-limestones-implications-for-its-taphonomy-and-paleoecology
#7
N Bykova, B C Gill, D Grazhdankin, V Rogov, S Xiao
The Ediacara biota features the rise of macroscopic complex life immediately before the Cambrian explosion. One of the most abundant and widely distributed elements of the Ediacara biota is the discoidal fossil Aspidella, which is interpreted as a subsurface holdfast possibly anchoring a frondose epibenthic organism. It is a morphologically simple fossil preserved mainly in siliciclastic rocks, which are unsuitable for comprehensive stable isotope geochemical analyses to decipher its taphonomy and paleoecology...
April 11, 2017: Geobiology
https://www.readbyqxmd.com/read/28387009/paleoecology-and-paleoceanography-of-the-athel-silicilyte-ediacaran-cambrian-boundary-sultanate-of-oman
#8
D A Stolper, G D Love, S Bates, T W Lyons, E Young, A L Sessions, J P Grotzinger
The Athel silicilyte is an enigmatic, hundreds of meters thick, finely laminated quartz deposit, in which silica precipitated in deep water (>~100-200 m) at the Ediacaran-Cambrian boundary in the South Oman Salt Basin. In contrast, Meso-Neoproterozoic sinks for marine silica were dominantly restricted to peritidal settings. The silicilyte is known to contain sterane biomarkers for demosponges, which today are benthic, obligately aerobic organisms. However, the basin has previously been described as permanently sulfidic and time-equivalent shallow-water carbonate platform and evaporitic facies lack silica...
May 2017: Geobiology
https://www.readbyqxmd.com/read/28384568/combination-of-a-crop-model-and-a-geochemical-model-as-a-new-approach-to-evaluate-the-sustainability-of-an-intensive-agriculture-system
#9
Gihan Mohammed, Fabienne Trolard, Marina Gillon, Anne-Laure Cognard-Plancq, André Chanzy, Guilhem Bourrié
By combining a crop model (STICS) and a geochemical model (PHREEQC), a new approach to assess the sustainability of agrosystems is proposed. It is based upon aqueous geochemistry and the stepwise modifications of soil solution during its transfer from the surface till aquifer. Meadows of Crau (SE France), irrigated since the 16th century, were field monitored (2012-2015) and modelled. Except for N, the mineral requirements of hay are largely covered by dissolved elements brought by irrigation water with only slight deficits in K and P, which are compensated by P-K fertilizers and the winter pasture by sheep...
April 3, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28384184/assessing-biosynthetic-potential-of-agricultural-groundwater-through-metagenomic-sequencing-a-diverse-anammox-community-dominates-nitrate-rich-groundwater
#10
William B Ludington, Thaddeus D Seher, Olin Applegate, Xunde Li, Joseph I Kliegman, Charles Langelier, Edward R Atwill, Thomas Harter, Joseph L DeRisi
BACKGROUND: Climate change produces extremes in both temperature and precipitation causing increased drought severity and increased reliance on groundwater resources. Agricultural practices, which rely on groundwater, are sensitive to but also sources of contaminants, including nitrate. How agricultural contamination drives groundwater geochemistry through microbial metabolism is poorly understood. METHODS: On an active cow dairy in the Central Valley of California, we sampled groundwater from three wells at depths of 4...
2017: PloS One
https://www.readbyqxmd.com/read/28373716/microbial-functional-capacity-is-preserved-within-engineered-soil-formulations-used-in-mine-site-restoration
#11
Deepak Kumaresan, Adam T Cross, Benjamin Moreira-Grez, Khalil Kariman, Paul Nevill, Jason Stevens, Richard J N Allcock, Anthony G O'Donnell, Kingsley W Dixon, Andrew S Whiteley
Mining of mineral resources produces substantial volumes of crushed rock based wastes that are characterised by poor physical structure and hydrology, unstable geochemistry and potentially toxic chemical conditions. Recycling of these substrates is desirable and can be achieved by blending waste with native soil to form a 'novel substrate' which may be used in future landscape restoration. However, these post-mining substrate based 'soils' are likely to contain significant abiotic constraints for both plant and microbial growth...
April 3, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28371710/redox-chemistry-of-nickel-in-soils-and-sediments-a-review
#12
Jörg Rinklebe, Sabry M Shaheen
Knowledge on the redox geochemistry of Ni is behind in comparison to other heavy metals. Hence, this article reviews the direct and indirect impact of redox potential (EH) on mobilization and release dynamics of Ni in soils and sediments across the world. Nickel can show a different behavior in response to EH. Mobilization of Ni increased at low EH in various soils; however, oxic conditions can lead to an increased mobilization of Ni in other soils. Those differences occur because the mobilization of Ni is often indirectly affected by EH, e...
July 2017: Chemosphere
https://www.readbyqxmd.com/read/28371135/climate-and-geochemistry-as-drivers-of-eucalypt-diversification-in-australia
#13
E N Bui, A H Thornhill, C E González-Orozco, N Knerr, J T Miller
Eucalypts cover most of Australia. Here, we investigate the relative contribution of climate and geochemistry to the distribution and diversity of eucalypts. Using geostatistics, we estimate major element concentrations, pH, and electrical conductivity at sites where eucalypts have been recorded. We compare the median predicted geochemistry and reported substrate for individual species that appear associated with extreme conditions; this provides a partial evaluation of the predictions. We generate a site-by-species matrix by aggregating observations to the centroids of 100-km-wide grid cells, calculate diversity indices, and use numerical ecology methods (ordination, variation partitioning) to investigate the ecology of eucalypts and their response to climatic and geochemical gradients...
May 2017: Geobiology
https://www.readbyqxmd.com/read/28365477/reference-natural-radionuclide-concentrations-in-australian-soils-and-derived-terrestrial-air-kerma-rate
#14
R Kleinschmidt
Sediment from drainage catchment outlets has been shown to be a useful means of sampling large land masses for soil composition. Naturally occurring radioactive material concentrations (uranium, thorium and potassium-40) in soil have been collated and converted to activity concentrations using data collected from the National Geochemistry Survey of Australia. Average terrestrial air kerma rate data are derived using the elemental concentration data, and is tabulated for Australia and states for use as baseline reference information...
March 30, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28353054/application-of-artificial-neural-network-in-medical-geochemistry
#15
K Fajčíková, B Stehlíková, V Cvečková, S Rapant
For the evaluation of various adverse health effects of chemical elements occurring in the environment on humans, the comparison and linking of geochemical data (chemical composition of groundwater, soils, and dusts) with data on health status of population (so-called health indicators) play a key role. Geochemical and health data are predominantly nonlinear, and the use of standard statistical methods can lead to wrong conclusions. For linking such data, we find appropriate the use method of artificial neural networks (ANNs) which enable to eliminate data inhomogeneity and also potential data errors...
March 28, 2017: Environmental Geochemistry and Health
https://www.readbyqxmd.com/read/28349313/foliar-nutrient-and-metal-levels-of-crops-in-the-mount-cameroon-area-reference-values-for-plant-nutrition-and-environmental-monitoring
#16
J Franzaring, G E Mbaka, T F Ambebe, J N Nkengafac, S Schlosser, A Fangmeier
The growing population number and traffic loads, increasing environmental pressures, agricultural intensification, and the establishment of Mount Cameroon National Park demand farsighted environmental management in the region and the definition of a favorable ecological status. Since plants grow in the interface between soils and the atmosphere they can be used as passive biomonitors for the environmental quality. At the same time, the accumulation of nutrients and pollutants in crops is linked to human health, so that foliar elemental levels can be used as an integrative measure for environmental pollution and impact assessment...
April 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/28316048/toxic-elements-and-bio-metals-in-cantharellus-mushrooms-from-poland-and-china
#17
Jerzy Falandysz, Maria Chudzińska, Danuta Barałkiewicz, Małgorzata Drewnowska, Anetta Hanć
Data on multi-trace element composition and content relationships have been obtained for Cantharellus cibarius, C. tubaeformis, and C. minor mushrooms from Poland and China by inductive coupled plasma-dynamic reaction cell-mass spectroscopy. There is no previous data published on As, Li, V, Tl, and U in chanterelles from Poland and on Ba, Co, Cr, Ni, Rb, and Sr in chanterelles from China. The results implied a role of the soil background geochemistry at the collection site with the occurrence of Ag, As, Ba, Cr, Cs, Li, Mn, Pb, Rb, Sr, U, and V in the fruiting bodies...
March 18, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28296889/investigation-of-bacterial-communities-within-the-digestive-organs-of-the-hydrothermal-vent-shrimp-rimicaris-exoculata-provide-insights-into-holobiont-geographic-clustering
#18
Dominique A Cowart, Lucile Durand, Marie-Anne Cambon-Bonavita, Sophie Arnaud-Haond
Prokaryotic communities forming symbiotic relationships with the vent shrimp, Rimicaris exoculata, are well studied components of hydrothermal ecosystems at the Mid-Atlantic Ridge (MAR). Despite the tight link between host and symbiont, the observed lack of spatial genetic structure seen in R. exoculata contrasts with the geographic differentiation detected in specific bacterial ectosymbionts. The geographic clustering of bacterial lineages within a seemingly panmictic host suggests either the presence of finer scale restriction to gene flow not yet detected in the host, horizontal transmission (environmental selection) of its endosymbionts as a consequence of unique vent geochemistry, or vertically transmitted endosymbionts that exhibit genetic differentiation...
2017: PloS One
https://www.readbyqxmd.com/read/28291805/socioeconomic-factors-associated-with-severe-acute-malnutrition-in-jamaica
#19
Debbie S Thompson, Novie Younger-Coleman, Parris Lyew-Ayee, Lisa-Gaye Greene, Michael S Boyne, Terrence E Forrester
OBJECTIVES: Severe acute malnutrition (SAM) is an important risk factor for illness and death globally, contributing to more than half of deaths in children worldwide. We hypothesized that SAM is positively correlated to poverty, low educational attainment, major crime and higher mean soil concentrations of lead, cadmium and arsenic. METHODS: We reviewed admission records of infants admitted with a diagnosis of SAM over 14 years (2000-2013) in Jamaica. Poverty index, educational attainment, major crime and environmental heavy metal exposure were represented in a Geographic Information System (GIS)...
2017: PloS One
https://www.readbyqxmd.com/read/28285858/high-resolution-profile-of-inorganic-aqueous-geochemistry-and-key-redox-zones-in-an-arsenic-bearing-aquifer-in-cambodia
#20
Laura A Richards, Daniel Magnone, Chansopheaktra Sovann, Chivuth Kong, Sebastian Uhlemann, Oliver Kuras, Bart E van Dongen, Christopher J Ballentine, David A Polya
Arsenic contamination of groundwaters in South and Southeast Asia is a major threat to public health. In order to better understand the geochemical controls on the mobility of arsenic in a heavily arsenic-affected aquifer in northern Kandal Province, Cambodia, key changes in inorganic aqueous geochemistry have been monitored at high vertical and lateral resolution along dominant groundwater flow paths along two distinct transects. The two transects are characterized by differing geochemical, hydrological and lithological conditions...
March 9, 2017: Science of the Total Environment
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