A5090336889- Groundwater flow and contamination studies
- Hydrology and Watershed Management Studies
- Geophysical and Geoelectrical Methods
- Hydraulic Fracturing and Reservoir Analysis
- Groundwater and Isotope Geochemistry
- Reservoir Engineering and Simulation Methods
- Soil and Unsaturated Flow
- Soil and Water Nutrient Dynamics
- CO2 Sequestration and Geologic Interactions
- Enhanced Oil Recovery Techniques
- Wastewater Treatment and Nitrogen Removal
- Seismic Imaging and Inversion Techniques
- Radioactive element chemistry and processing
- Hydrology and Sediment Transport Processes
- Soil Geostatistics and Mapping
- Pharmaceutical and Antibiotic Environmental Impacts
- NMR spectroscopy and applications
- Hydrocarbon exploration and reservoir analysis
- Geological Modeling and Analysis
- Geochemistry and Geologic Mapping
- Geophysical Methods and Applications
- Microbial Community Ecology and Physiology
- Microbial bioremediation and biosurfactants
- Toxic Organic Pollutants Impact
- Water resources management and optimization
University of Tübingen
2016-2025
Charles River Laboratories (Netherlands)
2024
TH Bingen University of Applied Sciences
2023
John Wiley & Sons (United States)
2016-2020
Weatherford College
2015
Supply Chain Competence Center (Germany)
2013
Swiss Federal Institute of Aquatic Science and Technology
2004-2009
ETH Zurich
2008-2009
École Polytechnique Fédérale de Lausanne
2009
Université de Poitiers
2008
Abstract Headwater catchments are the fundamental units that connect land to ocean. Hydrological flow and biogeochemical processes intricately coupled, yet their respective sciences have progressed without much integration. Reaction kinetic theories prescribe rate dependence on environmental variables (e.g., temperature water content) advanced substantially, mostly in well‐mixed reactors, columns, warming experiments considering characteristics of hydrological at catchment scale. These shown...
In situ microbial reduction of soluble U(VI) to sparingly U(IV) was evaluated at the site former S-3 Ponds in Area 3 U.S. Department Energy Natural and Accelerated Bioremediation Research Field Center, Oak Ridge, TN. After establishing conditions favorable for bioremediation (Wu, et al. Environ. Sci. Technol. 2006, 40, 3988−3995), intermittent additions ethanol were initiated within conditioned inner loop a nested well recirculation system. These initially stimulated denitrification...
To evaluate the potential for in situ bioremediation of U(VI) to sparingly soluble U(IV), we constructed a pilot test facility at Area 3 U.S. Department Energy Natural and Accelerated Bioremediation Research (NABIR) Field Center (FRC) Oak Ridge, TN. The is adjacent former S-3 Ponds which received trillions liters acidic plating wastes. High levels uranium are present, with up 800 mg kg-1 soil 84−210 μM groundwater. Ambient groundwater has highly buffered pH ∼3.4 high aluminum (12−13 mM),...
Transverse dispersion across adjacent streamlines can control the amount of mixing and reaction between one or more contaminants a limiting substrate along fringes groundwater plumes. Streamlines in converge diverge heterogeneous porous media, depending on permeability distribution. When flow is focused high‐permeability zone, distance required for solute to cross given number decreases, time allowed reduced. Because first effect outweighs latter, overall result an enhancement transverse...
Abstract Knowing the travel‐time distributions from infiltrating rivers to pumping wells is important in management of alluvial aquifers. Commonly, are determined by releasing a tracer pulse into river and measuring breakthrough curve wells. As an alternative, one may measure signals time‐varying natural adjacent infer deconvolution. Traditionally this done fitting parametric function such as solution one‐dimensional advection‐dispersion equation data. By choosing certain parameterization,...
In aqueous environments, hydrophobic organic contaminants are often associated with particles. Besides natural particles, microplastics have raised public concern. The release of pollutants from such particles depends on mass transfer, either in an boundary layer or by intraparticle diffusion. Which these mechanisms controls the mass-transfer kinetics partition coefficients, particle size, conditions, and time. We developed a semianalytical model accounting for both processes performed batch...
Abstract Shallow benthic biolayers at the top of streambed are believed to be places enhanced biogeochemical turnover within hyporheic zone. They can investigated by reactive stream tracer tests with recordings in and channel. Common in‐stream measurements such tracers cannot localize where processing primarily takes place, whereas isolated vertical depth profiles solutes zone usually not representative entire stream. We present results a test we injected conservative bromide together...
Groundwater–surface-water (GW-SW) interactions in streams are difficult to quantify because of heterogeneity hydraulic and reactive processes across a range spatial temporal scales. The challenge quantifying these has led the development several techniques, from centimeter-scale probes whole-system tracers, including chemical, thermal, electrical methods. We co-applied conservative smart solute-tracer tests, measurement heads, distributed temperature sensing, vertical profiles solute tracer...
Geogenic arsenic (As) contamination of groundwater poses a major threat to global health, particularly in Asia. To mitigate this exposure, is increasingly extracted from low-As Pleistocene aquifers. This, however, disturbs flow and potentially draws high-As into Here we report detailed characterisation the Van Phuc aquifer Red River Delta region, Vietnam, where Holocene being drawn aquifer. This study includes data eight years (2010-2017) observations develop an understanding spatial...
Redox-active organic molecules such as anthraquinone-2,6-disulfonate (AQDS) and natural matter (NOM) can act electron shuttles thus facilitating transfer from Fe(III)-reducing bacteria (FeRB) to terminal acceptors Fe(III) minerals. In this research, we examined the length scale over which shuttling occur. We present results agar-solidified experimental incubations, containing either AQDS or NOM, where FeRB were physically separated ferrihydrite goethite by 2 cm. Iron speciation concentration...
Breakthrough curves of a conservative tracer in heterogeneous two‐dimensional aquifer are analyzed by means their temporal moments. The average velocity and the longitudinal macrodispersion coefficient equivalent one‐dimensional obtained through cross‐sectional averaging concentration can be defined from first second central moments breakthrough curve integrated over outflow boundary domain. On basis an curve, one cannot distinguish between actual solute dilution, which involves reduction,...
The contamination of groundwater by geogenic arsenic is the cause major health problems in south and southeast Asia. Various hypotheses proposing that As mobilized reduction iron (oxy)hydroxides are now under discussion. One important controversial question concerns possibility might be related to extraction for irrigation purposes. If were inflow re-infiltrating water rich labile organic carbon, As-contaminated would have been recharged after introduction 20-40 years ago. We used...
The conventional analysis of pumping tests by type‐curve methods is based on the assumption a homogeneous aquifer. Applying these techniques to test data from real heterogeneous aquifers leads estimates hydraulic parameters that depend choice and observation well positions. In this paper, we whether values may be viewed as pseudo‐local transmissivity storativity, which can interpolated kriging. We compare such those obtained geostatistical inverse modeling, where heterogeneity assumed in all...
Mass transfer, mixing, and therefore reaction rates during transport of solutes in porous media strongly depend on dispersion diffusion. In particular, transverse mixing is a significant mechanism controlling natural attenuation contaminant plumes groundwater. The aim the present study to gain deeper understanding vertical dispersive partners saturated media. Multitracer laboratory experiments quasi two-dimensional tank filled with glass beads were conducted coefficients determined from...
Structural Fe(II) in clay minerals is an important source of electron equivalents for the reductive transformation contaminants anoxic environments. We investigated which factors control reactivity smectites including total Fe content, Fe(II)/total ratio, and excess negative charge localization using 10 nitroaromatic compounds (NACs) as reactive probe molecules. Based on evidence from this work previous spectroscopic studies redox reactions iron-rich smectites, we propose a kinetic model...
Abstract The Qaidam Basin is the largest intermontane basin of northeastern Tibetan Plateau and contains a continuous Cenozoic sequence lacustrine sediments. A ~ 1000-m-deep drilling (SG-1) with an average core recovery 95% was carried out in depocenter Chahansilatu playa (sub-depression) western Basin, aimed to obtain high-resolution record paleoenvironmental evolution erosion history. Stepwise alternating field thermal demagnetization, together rock magnetic results, revealed stable...
We perform a salt tracer experiment, monitored by time‐lapse electrical resistivity tomography, in quasi‐two‐dimensional sandbox with the aim of determining hydraulic conductivity distribution domain. use sodium chloride as tracer, together cochineal red for visual monitoring. The time series observed resistance each electrode configuration is characterized its temporal moments. invert mean arrival potential perturbations and few steady state head measurements using fully coupled...
Groundwater plumes originating from continuously emitting sources are typically controlled by transverse mixing between the plume and reactants in ambient solution. In two-dimensional domains, heterogeneity causes only weak enhancement of steady-state flows. three-dimensional more complex flow patterns possible because streamlines can twist. particular, spatially varying orientation anisotropy cause groundwater whirls. We analyze solute transport locally isotropic heterogeneous porous media...