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Author Edmunds, W.M.; Shand, P.; Hart, P.; Ward, R.S. url  openurl
  Title The natural (baseline) quality of groundwater: a UK pilot study Type Journal Article
  Year 2003 Publication Science of The Total Environment Abbreviated Journal  
  Volume 310 Issue 1 Pages 25-35  
  Keywords Baseline quality, Groundwater, Hydrogeochemistry, Monitoring, Water Policy  
  Abstract Knowledge of the natural baseline quality of groundwaters is an essential prerequisite for understanding pollution and for imposing regulatory limits. The natural baseline of groundwaters may show a range of concentrations depending on aquifer mineralogy, facies changes, flow paths and residence time. The geochemical controls on natural concentrations are discussed and an approach to defining baseline concentrations using geochemical and statistical tools is proposed. The approach is illustrated using a flowline from the Chalk aquifer in Berkshire, UK where aerobic and anaerobic sections of the aquifer are separately considered. The baseline concentrations for some elements are close to atmospheric values whereas others evolve through time-dependent water–rock interaction. Certain solutes (K, NH4+), often considered contaminants, reach naturally high concentrations due to geochemical controls; transition metal concentrations are generally low, although their concentrations may be modified by redox controls. It is recommended that the baseline approach be incorporated into future management strategies, notably monitoring.  
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  ISSN 0048-9697 ISBN Medium  
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  Notes Approved no  
  Call Number (up) THL @ christoph.kuells @ edmunds_natural_2003 Serial 166  
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Author Etschmann, B.; Liu, W.; Li, K.; Dai, S.; Reith, F.; Falconer, D.; Kerr, G.; Paterson, D.; Howard, D.; Kappen, P.; Wykes, J.; Brugger, J. url  openurl
  Title Enrichment of germanium and associated arsenic and tungsten in coal and roll-front uranium deposits Type Journal Article
  Year 2017 Publication Chemical Geology Abbreviated Journal  
  Volume 463 Issue Pages 29-49  
  Keywords Arsenic, Coal, EXAFS and XANES, germanium, Hydrothermal fluids, Metallogenesis, Speciation, Tungsten  
  Abstract Most of the World’s germanium (Ge) is mined from Ge-rich lignite, where it is commonly associated with elevated arsenic (As), tungsten (W) and beryllium (Be) contents. Over the past decade, new evidence showing that World-class Ge deposits result from the interaction of hydrothermal fluids with organic matter in coal seams has emerged. Yet, the chemical state of Ge and associated metals in lignite remains poorly understood. We used Mega-pixel Synchrotron X-ray Fluorescence (MSXRF), X-ray Absorption Near Edge Structure (XANES) and Extended X-ray Absorption Fine Structure (EXAFS) to characterize the oxidation states and chemical bonding environment of Ge, As, and W in two world-class Mesozoic Ge-in-lignite deposits (Lincang, Yunnan, southwestern China; Wulantuga, Inner Mongolia, northeastern China); in lignite-bearing uranium (U) ores from the Beverley deposit (South Australia) hosted in Eocene sandstones; and in lignite and preserved wood in late Oligocene-Miocene fluviatile sediments (Gore, Southland, New Zealand). The aim was to improve our understanding of the enrichment mechanism of Ge in lignite and better evaluate the environmental mobility of Ge and some of the associated metals (specifically As and W) in lignite ores. In all samples, chemical maps show that Ge is distributed homogeneously (down to 2μm) within the organic matter. XANES and EXAFS data show that Ge exists in the tetravalent oxidation state and in a distorted octahedral coordination with O, consistent with complexing of Ge by organic ligands. In some pyrite-bearing samples, a minor fraction of Ge is also present as Ge(IV) in association with pyrite. In contrast, As displays a more complex speciation pattern, sometimes even in a single sample, including As(III), As(V), and As(−I/+II) in solid solution in sulfides. Arsenic in sulfides occurs in anionic and cationic forms, i.e., it shows both the common substitution for S22− and the substitution for Fe recently discovered in some hydrothermal pyrites. Tungsten was present as W(VI) in distorted octahedral (3+3) coordination. The EXAFS data confirm the absence or minor contribution of individual W-rich minerals such as scheelite or ferberite to W mass balance in the studied samples. These data show that Ge, W, and probably some As are scavenged via formation of insoluble, oxygen-bridged metal organic complexes in lignite. Destruction of the organic ligands responsible for fixing Ge and W (As) in these lignites is required for liberating the metals, e.g. from waste materials. Geochemical modelling suggests that Ge, W, Be and As all can be extracted from granitic rocks by dilute, low temperature hydrothermal fluids. Germanium is transported mainly as the tetrahedral Ge(OH)4(aq) complex, but fixed as an octahedral oxy-bridged organic complex. The same situation is valid for W, which is transported at the tetrahedral tungstate ion, but most likely scavenged via formation of a 6-coordinated metal-organic species. The Ge-Be-W±As association in Ge-rich coals reflects the source of the metals as well as related scavenging mechanisms.  
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  ISSN 0009-2541 ISBN Medium  
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  Notes Approved no  
  Call Number (up) THL @ christoph.kuells @ etschmann_enrichment_2017 Serial 183  
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Author Pisa, P.F.; Nehren, U.; Sebesvari, Z.; Rai, S.; Wong, I. url  isbn
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  Title Chapter 17 – Nature-based solutions to reduce risks and build resilience in mountain regions Type Book Chapter
  Year 2024 Publication Safeguarding Mountain Social-Ecological Systems Abbreviated Journal  
  Volume Issue Pages 115-126  
  Keywords Nature-based solutions, mountains, climate change adaptation, disaster risk reduction, ecosystem services, SDGs  
  Abstract Nature-based solutions (NbS) are increasingly recognized as effective environmental-management measures to address societal challenges such as climate change, water and food security, and disaster risk reduction, thus contributing to human well-being and protecting biodiversity. In addition to being particularly susceptible to these challenges, mountain areas are prone to multihazard conditions, due to their steep topography and particular climatic conditions. NbS can contribute greatly to the sustainable development of mountain ecosystems. This chapter presents examples of NbS in mountain areas around the globe that demonstrate how this approach contributes to achieving sustainable development.  
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  Publisher Elsevier Place of Publication Editor Schneiderbauer, S.; Pisa, P.F.; Shroder, J.F.; Szarzynski, J.  
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  ISSN ISBN 978-0-12-822095-5 Medium  
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  Notes Approved no  
  Call Number (up) THL @ christoph.kuells @ Fontanellapisa2024115 Serial 263  
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Author French, K. url  openurl
  Title Indigenous knowledge, water management, and learning from our collective past Type Journal Article
  Year 2022 Publication Journal of Anthropological Archaeology Abbreviated Journal  
  Volume 68 Issue Pages 101466  
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  ISSN 0278-4165 ISBN Medium  
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  Notes Approved no  
  Call Number (up) THL @ christoph.kuells @ French2022101466 Serial 253  
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Author Frey, S.; Külls, C.; Schlosser, C. openurl 
  Title New Hydrological Age-Dating techniques using cosmogenic radionuclides Beryllium-7 and Sodium-22 Type Conference Article
  Year 2011 Publication Proc. IAEA Conf. Monacco Abbreviated Journal  
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  Notes Approved no  
  Call Number (up) THL @ christoph.kuells @ Frey2011new Serial 48  
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