Environmental Biogeochemistry Research Articles

Spatially Resolved Elemental Analysis, Spectroscopy and Diffraction at the GSECARS Sector at the Advanced Photon Source.

X-ray microprobes (XRM) coupled with high-brightness synchrotron X-ray facilities are powerful tools for environmental biogeochemistry research. One such instrument, the XRM at the Geo Soil Enviro Center for Advanced Radiation Sources Sector 13 at the Advanced Photon Source (APS; Argonne National Laboratory, Lemont, IL) was recently improved as part of a canted undulator geometry upgrade of the insertion device port, effectively doubling the available undulator beam time and extending the operating energy of the branch supporting the XRM down to the sulfur K edge (2.3 keV). Capabilities include rapid, high-resolution, elemental imaging including fluorescence microtomography, microscale X-ray absorption fine structure spectroscopy including sulfur K edge capability, and microscale X-ray diffraction. These capabilities are advantageous for (i) two-dimensional elemental mapping of relatively large samples at high resolution, with the dwell times typically limited only by the count times needed to obtain usable counting statistics for low concentration elements, (ii) three-dimensional imaging of internal elemental distributions in fragile hydrated specimens, such as biological tissues, avoiding the need for physical slicing, (iii) spatially resolved speciation determinations of contaminants in environmental materials, and (iv) identification of contaminant host phases. In this paper, we describe the XRM instrumentation, techniques, applications demonstrating these capabilities, and prospects for further improvements associated with the proposed upgrade of the APS.

High-Energy Resolution Fluorescence Detected X-Ray Absorption Spectroscopy: A Powerful New Structural Tool in Environmental Biogeochemistry Sciences.

The study of the speciation of highly diluted elements by X-ray absorption spectroscopy (XAS) is extremely challenging, especially in environmental biogeochemistry sciences. Here we present an innovative synchrotron spectroscopy technique: high-energy resolution fluorescence detected XAS (HERFD-XAS). With this approach, measurement of the XAS signal in fluorescence mode using a crystal analyzer spectrometer with a ∼1-eV energy resolution helps to overcome restrictions on sample concentrations that can be typically measured with a solid-state detector. We briefly describe the method, from both an instrumental and spectroscopic point of view, and emphasize the effects of energy resolution on the XAS measurements. We then illustrate the positive impact of this technique in terms of detection limit with two examples dealing with Ce in ecologically relevant organisms and with Hg species in natural environments. The sharp and well-marked features of the HERFD-X-ray absorption near-edge structure spectra obtained enable us to determine unambiguously and with greater precision the speciation of the probed elements. This is a major technological advance, with strong benefits for the study of highly diluted elements using XAS. It also opens new possibilities to explore the speciation of a target chemical element at natural concentration levels, which is critical in the fields of environmental and biogeochemistry sciences.

Introduction to the Special Issue on the 22nd International Symposium on Environmental Biogeochemistry Sponsored by the International Society for Environmental Biogeochemistry (ISEB)

For more than 40 years the International Society for Environmental Biogeochemistry (ISEB) has been devoted to the development of scientific knowledge, application, and training in the broader field...

Characteristics of Anaerobic Methane Removal Coupled to Fe(Ⅲ) Reduction in Aged Refuse

Landfills are the third largest iron reservoir and one of the largest sources of methane release. Iron, as a kind of transition metal, plays a particularly important role in environmental biogeochemistry and is closely linked to the biogeochemical cycle of C, S and N. The aged refuse could be utilized as bio-cover material to improve the removal of contaminants. Therefore, this work investigated the effect of iron reduction on anaerobic removal of methane, and the interactions of ferric iron with nitrate and sulfate in the aged refuse. The columns were operated as landfill bio-covers and recirculated leachate with addition of FeCl3 solution. In the experiment, three columns were used, two of them were used as controls (named as B1 and B3), B1 was fed with leachate and CH4, whereas B3 was only recirculated with leachate adding FeCl3. The treatment B2 was fed with the above two substrates. During the operation of columns, the contents of CH4, CO2 and N2 in the gas, and the concentrations of NO3-, NO2-, NH4+, SO42-, Fe(Ⅲ) and Fe(Ⅱ) in the leachate and refuse were respectively determined. The results showed that adding ferric iron obviously enhanced the removal of methane in anaerobic aged refuse, the decrease of methane content with time obeyed zero-order kinetic, and the rate of methane removal(denoted as CH4/aged refuse)reached 1.28 mmol·(kg·d)-1. In the anaerobic condition, methane could improve the reduction of Fe(Ⅲ) to dissolved, active and bioavailable Fe(Ⅱ). The active Fe(Ⅱ) probably coupled to the transformation of NO3- and SO42-, and thus accelerated the removal of NO3- and SO42-.

Optimizing Available Network Resources to Address Questions in Environmental Biogeochemistry

An increasing number of network observatories have been established globally to collect long-term biogeochemical data at multiple spatial and temporal scales. Although many outstanding questions in biogeochemistry would benefit from network science, the ability of the earth- and environmental-sciences community to conduct synthesis studies within and across networks is limited and seldom done satisfactorily. We identify the ideal characteristics of networks, common problems with using data, and key improvements to strengthen intra- and internetwork compatibility. We suggest that targeted improvements to existing networks should include promoting standardization in data collection, developing incentives to promote rapid data release to the public, and increasing the ability of investigators to conduct their own studies across sites. Internetwork efforts should include identifying a standard measurement suite—we propose profiles of plant canopy and soil properties—and an online, searchable data portal that connects network, investigator-led, and citizen-science projects.

COST action TD1407: network on technology-critical elements (NOTICE)--from environmental processes to human health threats.

The current socio-economic, environmental and public health challenges that countries are facing clearly need common-defined strategies to inform and support our transition to a sustainable economy. Here, the technology-critical elements (which includes Ga, Ge, In, Te, Nb, Ta, Tl, the Platinum Group Elements and most of the rare-earth elements) are of great relevance in the development of emerging key technologies—including renewable energy, energy efficiency, electronics or the aerospace industry. In this context, the increasing use of technology-critical elements (TCEs) and associated environmental impacts (from mining to end-of-life waste products) is not restricted to a national level but covers most likely a global scale. Accordingly, the European COST Action TD1407: Network on Technology-Critical Elements (NOTICE)—from environmental processes to human health threats, has an overall objective for creating a network of scientists and practitioners interested in TCEs, from the evaluation of their environmental processes to understanding potential human health threats, with the aim of defining the current state of knowledge and gaps, proposing priority research lines/activities and acting as a platform for new collaborations and joint research projects. The Action is focused on three major scientific areas: (i) analytical chemistry, (ii) environmental biogeochemistry and (iii) human exposure and (eco)-toxicology.

Selenium in soils under climate change, implication for human health

Global climate changes can alter the suitable geographical range of different crops, leading to possible changes in cropping pattern and its extent in some regions. For example, temperature changes can interact very closely with changes in availability of water and soil nutrients, and crop growth cycle. The consequences of the biophysical impacts of climate changes will be influenced by the human responses to these impacts. There is a strong link between soils and human health, and these soils per se are controlled by climate changes. The human health is very close to both selenium (Se) element and climate changes. It is estimated that about 37–40 % of the total Se emissions to the atmosphere are due to the anthropogenic activities. Those anthropogenic activities, which are sources of Se, include coal and oil combustion, mining activities, the utilization of rock phosphates as a fertilizer and the application of sewage sludge to agricultural land. It was thought that selenium was a toxicant for a long time due to inadequate analytical data. In the recent past, Se has become very important in environmental biogeochemistry because of its influence on human health. Although Se is an essential nutrient for animals and humans, it is also toxic at high doses. Furthermore, the range between Se deficiency, lower than 40 μg day−1, and toxicity, higher than 400 μg day−1, is narrow. Selenium deficiency has been linked to several human diseases including multiple sclerosis, muscular dystrophy, heart disease, immune system, cancer and reproductive disorders. On the other hand, Se toxicity can lead to hair and nail loss and disruption of the nervous and digestive systems in animals and humans. Despite the obvious connections between Se element and human health under climate changes, there has not been a great amount of research done in this area. So, more and more studies should be carried out to enhance and protect human health. Therefore, this article reviews the biological and economic dimensions of the effects of Se element on human health under climate changes.

AGU to Launch a New Open‐Access Journal Spanning the Earth and Space Sciences

AGU is pleased to announce a new, fully open‐access journal, Earth and Space Science (ESS), that will reflect the expansive range of science represented by AGU's members. ESS will publish research papers spanning all of the Earth, planetary, and space sciences, including related fields in environmental science, geoengineering, space engineering, and biogeochemistry.

Using Soil Science to Remove Arsenic from Water in Asia: A Day in the Life of Matt Polizzotto

Using Soil Science to Remove Arsenic from Water in Asia: A Day in the Life of Matt Polizzotto

Leaching of Trace Metals from Soil under Alternating Oxic-anoxic Conditions: a Column Study

One of the most important and abundant transition metals in the Earth's crust is iron, which plays a key role in environmental biogeochemistry. A large number of trace metals and other contaminants are associated to Fe(III) minerals; under anoxic conditions, Fe(III) can be reduced and, consequently, potentially dangerous compounds can be released. In this work we present column experiments of metal mobilization from soils sampled from a mining area in Northeastern Romania. A preliminary study was carried out to determine the extractability of metals in CaCl2 0.01 M solution and the influence of adding 1 g L -1 lactose as a carbon source. The results showed that the heavy metals were rapidly brought into solution in the medium supplemented with lactose. Then, the release of metals was studied using columns packed with soil percolated with the CaCl2 solution. It was observed that, while Zn and Pb are released in the solution congruently with the reduction of Fe and Mn, copper is mobilized immediately and can be found in the leachate. This suggests that, under alternating oxic-anoxic conditions, the soil can become a source of contamination.

In-Situ Molecular-Level Elucidation of Organofluorine Binding Sites in a Whole Peat Soil

The chemical nature of xenobiotic binding sites in soils is of vital importance to environmental biogeochemistry. Interactions between xenobiotics and the naturally occurring organic constituents of soils are strongly correlated to environmental persistence, bioaccessibility, and ecotoxicity. Nevertheless, because of the complex structural and chemical heterogeneity of soils, studies of these interactions are most commonly performed indirectly, using correlative methods, fractionation, or chemical modification. Here we identify the organic components of an unmodified peat soil where some organofluorine xenobiotic compounds interact using direct molecular-level methods. Using (19)F→(1)H cross-polarization magic angle spinning (CP-MAS) nuclear magnetic resonance (NMR) spectroscopy, the (19)F nuclei of organofluorine compounds are used to induce observable transverse magnetization in the (1)H nuclei of organic components of the soil with which they interact after sorption. The observed (19)F→(1)H CP-MAS spectra and dynamics are compared to those produced using model soil organic compounds, lignin and albumin. It is found that lignin-like components can account for the interactions observed in this soil for heptafluoronaphthol (HFNap) while protein structures can account for the interactions observed for perfluorooctanoic acid (PFOA). This study employs novel comprehensive multi-phase (CMP) NMR technology that permits the application of solution-, gel-, and solid-state NMR experiments on intact soil samples in their swollen state.

ChemInform Abstract: Advanced in situ Spectroscopic Techniques and Their Applications in Environmental Biogeochemistry: Introduction to the Special Section

AbstractReview: 96 refs.

Applications of Time-Resolved Laser Fluorescence Spectroscopy to the Environmental Biogeochemistry of Actinides

Time-resolved laser fluorescence spectroscopy (TRLFS) is a useful means of identifying certain actinide species resulting from various biogeochemical processes. In general, TRLFS differentiates chemical species of a fluorescent metal ion through analysis of different excitation and emission spectra and decay lifetimes. Although this spectroscopic technique has largely been applied to the analysis of actinide and lanthanide ions having fluorescence decay lifetimes on the order of microseconds, such as UO , Cm, and Eu, continuing development of ultra-fast and cryogenic TRLFS systems offers the possibility to obtain speciation information on metal ions having room-temperature fluorescence decay lifetimes on the order of nanoseconds to picoseconds. The main advantage of TRLFS over other advanced spectroscopic techniques is the ability to determine in situ metal speciation at environmentally relevant micromolar to picomolar concentrations. In the context of environmental biogeochemistry, TRLFS has principally been applied to studies of (i) metal speciation in aqueous and solid phases and (ii) the coordination environment of metal ions sorbed to mineral and bacterial surfaces. In this review, the principles of TRLFS are described, and the literature reporting the application of this methodology to the speciation of actinides in systems of biogeochemical interest is assessed. Significant developments in TRLFS methodology and advanced data analysis are highlighted, and we outline how these developments have the potential to further our mechanistic understanding of actinide biogeochemistry.

Advanced in situ Spectroscopic Techniques and their Applications in Environmental Biogeochemistry: Introduction to the Special Section

Understanding the molecular-scale complexities and interplay of chemical and biological processes of contaminants at solid, liquid, and gas interfaces is a fundamental and crucial element to enhance our understanding of anthropogenic environmental impacts. The ability to describe the complexity of environmental biogeochemical reaction mechanisms relies on our analytical ability through the application and developmemnt of advanced spectroscopic techniques. Accompanying this introductory article are nine papers that either review advanced in situ spectroscopic methods or present original research utilizing these techniques. This collection of articles summarizes the challenges facing environmental biogeochemistry, highlights the recent advances and scientific gaps, and provides an outlook into future research that may benefit from the use of in situ spectroscopic approaches. The use of synchrotron-based techniques and other methods are discussed in detail, as is the importance to integrate multiple analytical approaches to confirm results of complementary procedures or to fill data gaps. We also argue that future direction in research will be driven, in addition to recent analytical developments, by emerging factors such as the need for risk assessment of new materials (i.e., nanotechnologies) and the realization that biogeochemical processes need to be investigated in situ under environmentally relevant conditions.

Advisability of X‐ray fluorescence analysis of dry residue of cow milk applied to monitor environment

AbstractThe paper reports application of X‐ray fluorescence (XRF) procedure to determine the contents of 17 elements (Na, Mg, Al, Si, P, S, Cl, K, Ca, Mn, Fe, Ni, Cu, Zn, Rb, Sr, and Zr) in a dry residue of cow milk. The main advantages of this procedure imply: preparation of samples without having them destructed, use of plant reference samples (RS) to calibrate, no need for milk defatting, and, as a consequence, no limitations for the milk fatness. The tendencies identified with the XRF results on the dry residue of cow milk do not contradict the features recognized in environmental biogeochemistry. They designate a satisfactory quality of XRF results and prove them promising for multipurpose interpretations. Copyright © 2009 John Wiley & Sons, Ltd.

Abstracts of Nippon Dojo-Hiryogaku Zasshi

Abstracts of Nippon Dojo-Hiryogaku Zasshi

Report on 18th International Symposium on Environmental Biogeochemistry

Report on 18th International Symposium on Environmental Biogeochemistry

JANET G. HERING

IN SWITZERLAND, postdoctoral fellows contribute to pension funds. So when Janet G. Hering finished her postdoc at the Swiss Federal Institute of Aquatic Science & Technology (Eawag) and was asked whether she wanted to leave her pension in in case she returned, she replied firmly. No. I'm going to live in the U.S. She could not have known that she would be back about 15 years later. In January, Hering took up residence in as a professor of environmental biogeochemistry at the Swiss Federal Institute of Technology (ETH), Zurich, and director of Eawag. The ETH Domain, the only federal organization for research and education in Switzerland, consists of two universities (ETH and EPF Lausanne) and four research institutes, including Eawag. Hering is the first woman and one of the few non-Swiss to lead one of these institutions. Eawag (pronounced EH-vhaag) is in Diibendorf, near Zurich. Switzerland is a very small country that is ...

ISSM-ISEB 2005: Progress in Understanding and Predicting Subsurface Microbiology and Biogeochemical Processes

Click to increase image sizeClick to decrease image size ACKNOWLEDGEMENTS As always, many individuals and organizations are responsible for supporting and running successful meetings. Lori Smith, Lori Feinman and Alan Richards from the American Society for Microbiology deserve special recognition for coordinating and helping us execute all the various parts and details of the meeting. They deserve special praise. Generous funding support was provided by the Idaho National Laboratory, The Department of Energy Office of Science (Basic Energy Sciences/Geosciences and Biological and Environmental Research/Environmental Remediation Science), The National Atmospheric and Oceanographic Administration, the Inland Northwest Research Alliance, Inc., The University of New Hampshire Bedrock Bioremediation Center, the American Society for Microbiology, the International Symposium on Environmental Biogeochemistry, and the International Society for Subsurface Microbiology.

Environmental Biogeochemistry Studied by Second-Harmonic Generation: A Look at the Agricultural Antibiotic Oxytetracycline

The binding behavior of the veterinary antibiotic oxytetracycline (OTC) to tailor-made environmental interfaces was investigated using second-harmonic generation (SHG). Specifically, four environmentally relevant chemical moieties were covalently tethered to fused quartz surfaces using silane and amide coupling chemistry to survey how amides, polyfunctional binding sites, and phenyl rings that are common in humic acids control OTC binding at pH 8. The model geochemical surfaces prepared for this study were the following: methylamide-terminated fused quartz as well as amide-linked carboxylic acid-, benzoic acid-, and benzyl-terminated fused quartz. We find that amide-linked benzoic acid-terminated silanes display the highest equilibrium binding constant (1.1 × 106 M-1) among the systems surveyed. A straightforward predictive method of using contact angle measurements and the corresponding interfacial energy densities to predict OTC mobility across humic acid-containing mineral/water interfaces is discussed in the context of the emerging bacterial antibiotic resistance development threat.