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Author Holmes, M.; Campbell, E.E.; Wit, M. de; Taylor, J.C.
Title Can diatoms be used as a biomonitoring tool for surface and groundwater?: Towards a baseline for Karoo water Type Journal Article
Year 2023 Publication South African Journal of Botany Abbreviated Journal
Volume 161 Issue Pages (up) 211-221
Keywords Bioindicator, Diatom, Hydraulic fracturing, Karoo, Water quality
Abstract The environmental risks from shale gas extraction through the unconventional method of ‘fracking’ are considerable and impact on water supplies below and above ground. Since 2010 the recovery of natural shale gas through fracking has been proposed in parts of the fragile semi-arid ecosystems that make up the Karoo biome in South Africa. These unique ecosystems are heavily reliant on underground water, intermittent and ephemeral springs, which are at great risk of contamination by fracking processes. Diatoms are present in all water bodies and reflect aspects of the environment in which they are located. As the possibility of fracking has not been removed, the aim of the project was to determine if diatoms could be used for rapid biomonitoring of underground and surface waters in the Karoo. Over a period of 24 months, water samples and diatom species were collected simultaneously from 65 sites. A total of 388 diatom taxa were identified from 290 samples with seasonal and substrate variation affecting species composition but not the environmental information. Species diversity information, on the other hand, often varied significantly between substrates within a single sample. Analysis using CCA established that the diatom composition was affected by lithium, oxidized nitrogen, electrical conductivity, and sulphate levels in the sampled water. We conclude that changes in diatom community composition in the Karoo do reflect the water chemistry and could be useful as bioindicators.
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ISSN 0254-6299 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ holmes_can_2023 Serial 163
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Author Mühr-Ebert, E.L.; Wagner, F.; Walther, C.
Title Speciation of uranium: Compilation of a thermodynamic database and its experimental evaluation using different analytical techniques Type Journal Article
Year 2019 Publication Applied Geochemistry Abbreviated Journal
Volume 100 Issue Pages (up) 213-222
Keywords
Abstract Environmental hazards are caused by uranium mining legacies and enhanced radioactivity in utilized groundwater and surface water resources. Knowledge of uranium speciation in these waters is essential for predicting radionuclide migration and for installing effective water purification technology. The validity of the thermodynamic data for the environmental media affected by uranium mining legacies is of utmost importance. Therefore, a comprehensive and consistent database was established according to current knowledge. The uranium data included in the database is based on the NEA TDB (Guillaumont et al., 2003) and is modified or supplemented as necessary e.g. for calcium and magnesium uranyl carbonates. The specific ion interaction theory (Brönsted, 1922) is used to estimate activity constants, which is sufficient for the considered low ionic strengths. The success of this approach was evaluated by comparative experimental investigations and model calculations (PHREEQC (Parkhurst and Appelo, 1999)) for several model systems. The waters differ in pH (2.7–9.8), uranium concentration (10−9-10−4 mol/L) and ionic strength (0.002–0.2 mol/L). We used chemical extraction experiments, ESI-Orbitrap-MS and time-resolved laser-induced fluorescence spectroscopy (TRLFS) to measure the uranium speciation. The latter method is nonintrusive and therefore does not change the chemical composition of the investigated waters. This is very important, because any change of the system under study may also change the speciation.
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Series Volume Series Issue Edition
ISSN 0883-2927 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ muhr-ebert_speciation_2019 Serial 142
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Author Tanwer, N.; Arora, V.; Kant, K.; Singh, B.; Laura, J.S.; Khosla, B.
Title Chapter 17 – Prevalence of Uranium in groundwater of rural and urban regions of India Type Book Chapter
Year 2024 Publication Water Resources Management for Rural Development Abbreviated Journal
Volume Issue Pages (up) 213-234
Keywords Distribution, Heath impacts, Remediation techniques, Sources, Uranium
Abstract Abnormally high uranium (U) prevalence in groundwater is a neoteric subject of concern throughout the world because of its direct impact on human health and well-being. Groundwater is used as the most preferred choice for drinking because of its good quality and ease of availability in rural and urban parts of India, and also in different parts of the world. India is an agriculture-dominant country and its 50–80% irrigational requirement is met by groundwater, besides this nearly 90% of rural and 50% of urban water needs are fulfilled by groundwater. The uranium concentration in groundwater in different parts of India namely Punjab, Haryana, Rajasthan, Madhya Pradesh, Karnataka, etc. found to be varying from 0 mg/L to 1443 mg/L, and in different parts of the world, it is found up to 1400 mg/L in the countries like United States, Canada, Finland, Mongolia, Nigeria, South Korea, Pakistan, Burundi, China, Afghanistan, etc. Various natural factors such as geology, hydro-geochemistry, and prevailing conditions as well as anthropogenic factors including mining, nuclear activities, erratic use of fertilizers, and overexploitation of groundwater resources are responsible for adding uranium in groundwater. Groundwater is considered a primary source of uranium ingestion in human beings as it contributes 85% while food contributes 15%. Uranium affects living beings as a two-way sword, being a radioactive element, causing radiotoxicity, and on the other hand as a heavy metal, it causes chemotoxicity. The main target organs affected by the consumption of uranium-contaminated water are kidneys, bones, lungs, etc. It can cause renal failure, impair cell functioning and bone growth, and mutation in DNA. Although, its toxic effects, being a heavy metal, are more severe than its radiotoxicity. Various techniques are available for the efficient removal of uranium from the groundwater such as bioremediation, nanotechnology-enhanced remediation, adsorption, filtration, etc. This chapter entails a comprehensive investigation of uranium contamination in groundwater of rural and urban parts of India their probable sources, health impacts, treatment, and mitigation techniques available to manage groundwater resources.
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Publisher Elsevier Place of Publication Editor Madhav, S.; Srivastav, A.L.; Izah, S.C.; Hullebusch, E. van
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 978-0-443-18778-0 Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ madhav_chapter_2024 Serial 152
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Author Yabusaki, S.B.; Fang, Y.; Long, P.E.; Resch, C.T.; Peacock, A.D.; Komlos, J.; Jaffe, P.R.; Morrison, S.J.; Dayvault, R.D.; White, D.C.; Anderson, R.T.
Title Uranium removal from groundwater via in situ biostimulation: Field-scale modeling of transport and biological processes Type Journal Article
Year 2007 Publication Journal of Contaminant Hydrology Abbreviated Journal
Volume 93 Issue 1 Pages (up) 216-235
Keywords Bioremediation, Biostimulation, Field experiment, Iron, Reactive transport, Sulfate, Uranium
Abstract During 2002 and 2003, bioremediation experiments in the unconfined aquifer of the Old Rifle UMTRA field site in western Colorado provided evidence for the immobilization of hexavalent uranium in groundwater by iron-reducing Geobacter sp. stimulated by acetate amendment. As the bioavailable Fe(III) terminal electron acceptor was depleted in the zone just downgradient of the acetate injection gallery, sulfate-reducing organisms came to dominate the microbial community. In the present study, we use multicomponent reactive transport modeling to analyze data from the 2002 field experiment to identify the dominant transport and biological processes controlling uranium mobility during biostimulation, and determine field-scale parameters for these modeled processes. The coupled process simulation approach was able to establish a quantitative characterization of the principal flow, transport, and reaction processes based on the 2002 field experiment, that could be applied without modification to describe the 2003 field experiment. Insights gained from this analysis include field-scale estimates of the bioavailable Fe(III) mineral threshold for the onset of sulfate reduction, and rates for the Fe(III), U(VI), and sulfate terminal electron accepting processes.
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Series Volume Series Issue Edition
ISSN 0169-7722 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ yabusaki_uranium_2007 Serial 156
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Author Hdeib, R.; Aouad, M.
Title Rainwater harvesting systems: An urban flood risk mitigation measure in arid areas Type Journal Article
Year 2023 Publication Water Science and Engineering Abbreviated Journal
Volume 16 Issue 3 Pages (up) 219-225
Keywords Rainwater harvesting, Urban floods, Flood map, Hydrodynamic model, Built environment, Arid areas
Abstract Rainwater harvesting (RWH) systems have been developed to compensate for shortage in the water supply worldwide. Such systems are not very common in arid areas, particularly in the Gulf Region, due to the scarcity of rainfall and their reduced efficiency in covering water demand and reducing water consumption rates. In spite of this, RWH systems have the potential to reduce urban flood risks, particularly in densely populated areas. This study aimed to assess the potential use of RWH systems as urban flood mitigation measures in arid areas. Their utility in the retention of stormwater runoff and the reduction of water depth and extent were evaluated. The study was conducted in a residential area in Bahrain that experienced waterlogging after heavy rainfall events. The water demand patterns of housing units were analyzed, and the daily water balance for RWH tanks was evaluated. The effect of the implementation of RWH systems on the flood volume was evaluated with a two-dimensional hydrodynamic model. Flood simulations were conducted in several rainfall scenarios with different probabilities of occurrence. The results showed significant reductions in the flood depth and flood extent, but these effects were highly dependent on the rainfall intensity of the event. RWH systems are effective flood mitigation measures, particularly in urban arid regions short of proper stormwater control infrastructure, and they enhance the resilience of the built environment to urban floods.
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Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1674-2370 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number THL @ christoph.kuells @ Hdeib2023219 Serial 242
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