Article
Environmental Sciences
Keith E. Schilling, Matthew T. Streeter
Summary: This study presents a paired water table monitoring approach to estimate the reduction of NO3-N loads from tile-drained croplands using saturated buffers. The results show that the saturated buffer can effectively increase the water table height and reduce the N concentration, resulting in a significant reduction in NO3-N loads.
ENVIRONMENTAL MONITORING AND ASSESSMENT
(2022)
Article
Environmental Sciences
Stephen J. Harris, Dioni Cendon, Stuart Hankin, Mark A. Peterson, Shuang Xiao, Bryce F. J. Kelly
Summary: The application of excessive nitrogen fertilisers can lead to nitrate contamination in groundwater, which can impact surface water quality. This study in the Emerald Irrigation Area, Australia, investigated the occurrence and controls of denitrification in nitrate-rich aquifers. The results showed that denitrification primarily occurs in anaerobic zones and beneath leaking irrigation channels, leading to significant nitrate reduction. Understanding regional and local hydrogeological processes is crucial for assessing the impacts of nitrate contamination on adjacent ecosystems.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Civil
Jie Li, Yulian Liu, Wei Dai, Jian Li, Pingheng Yang, Lijun Tian, Shihang Yu, Rui Zuo, Yuanzheng Zhai, Wei Song, Fan Yang, Ruijing Zhou, Shufang Wang
Summary: This study combines dual nitrate isotopes and microbial signatures to assess and quantify nitrate attenuation in the North China Plain. The results reveal significant denitrification using the dual nitrate isotopes on a temporal scale. High-throughput sequencing provides microbial evidence showing the relationship between the relative abundances of denitrification-related functional genes and nitrate concentration.
JOURNAL OF HYDROLOGY
(2023)
Article
Agronomy
Zheyu Xie, Yujing Zhang, Zhenyu Zhang, Jinliang Huang
Summary: A study in Southeast China reveals that the transition zone between rivers and riparian aquifers plays a crucial role in removing nitrate contamination from aquatic systems. The high connectivity between rivers and groundwater enhances the potential for nitrate removal. The study also highlights the significant contributions of manure and sewage, as well as soil and chemical fertilizers, to nitrate contamination.
AGRICULTURAL WATER MANAGEMENT
(2023)
Article
Environmental Sciences
Yasheng Shi, Cai Li, Zanfang Jin, Yongqi Zhang, Jiazheng Xiao, Feili Li
Summary: The study identified the sources and formation pathways of NO3- in Ningbo, revealing seasonal variations and suggesting that mobile sources are the major contributors to NOx emissions in the area. The research also emphasized the importance of considering isotopic fractionation in source apportionment models.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Review
Environmental Sciences
Amina Richa, Sami Touil, Meriem Fizir
Summary: This review introduces tracking tools for nitrate sources in groundwater and discusses methods for nitrate removal. Possible solutions to overcome the limitations of these methods are also proposed.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Environmental Sciences
Abdulhalim Zaryab, Hamid Reza Nassery, Kay Knoeller, Farshad Alijani, Eddy Minet
Summary: This study investigates the geochemistry and stable isotope composition of the Kabul urban aquifer, the main source of drinking water for Kabul city's inhabitants. The findings suggest that nitrate pollution in the aquifer primarily originates from sewage rather than artificial fertilizer. The results highlight the importance of improving sewage collection systems in the Kabul Plain.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Environmental
Yongge Zang, Xiaoshu Hou, Zhiping Li, Peng Li, Ying Sun, Bowei Yu, Miao Li
Summary: This study established a quasi-3D feedback model to quantitatively evaluate the effects of groundwater level (GWL) recovery on nitrate-N leaching fluxes and groundwater nitrate-N dynamics. The results showed that GWL recovery increased the nitrate-N leaching fluxes into the aquifer by 44.4% and the average groundwater nitrate-N concentration by approximately 2.4 mg/L.
Article
Engineering, Environmental
So Yeon Yoon, Min Ji Kim, Hye Won Kim, Seon Hwa Lim, Choe Earn Choong, Sang-Eun Oh, Jung Rae Kim, Yeomin Yoon, Jae young Choi, Eun Ha Choi, Min Jang
Summary: The aim of this study was to investigate the effects of hydrophilic sulfur-modified nanoscale zero-valent iron (S-nZVI) as a biocatalyst for denitrification. The researchers found that the denitrifying bacteria Cupriavidus necator promote Fe corrosion during biocatalytic denitrification, resulting in a higher synergistic factor for S-nZVI compared to nanoscale zero-valent iron. Kinetic profiles showed that the preferred electron acceptor for biocatalytic denitrification using S-nZVI and C. necator was SO42-, and up-flow column experiments demonstrated a high nitrogen removal capacity using S-nZVI for 127 days. Microbiome taxonomic profiling revealed that the addition of S-nZVI promoted the growth of specific microbes that can enhance denitrification.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Geosciences, Multidisciplinary
Guilherme E. H. Nogueira, Christian Schmidt, Daniel Partington, Philip Brunner, Jan H. Fleckenstein
Summary: Riparian zones play an important role in modulating water quality in stream corridors by acting as buffers or facilitating solute turnover. This study used a numerical model and hydraulic mixing cell method to investigate the source composition of water and its spatiotemporal evolution in Selke stream. The results showed the importance of discharge events and event intensity in increasing mixing potential.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)
Article
Environmental Sciences
Shengwei Cao, Yuhong Fei, Xia Tian, Xiangxiang Cui, Xueqing Zhang, Ruoxi Yuan, Yasong Li
Summary: The study reveals that human activities have a significant impact on the natural environment, with nitrate contamination primarily originating from sewage and manure, soil organic nitrogen, and synthetic fertilizer. Undeveloped infrastructure and sewage disposal in rural areas are the main causes of nitrate contamination.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Geosciences, Multidisciplinary
Louis Christiaens, Philippe Orban, Serge Brouyere, Pascal Goderniaux
Summary: This study combines hydrogeochemical and isotopic data with statistical methods to identify and spatialize different nitrate sources in the Mons Basin chalk aquifer in Belgium. By using t-SNE analysis, the study successfully differentiates various groups of samples and related zones in the aquifer. The results reveal four zones in the aquifer and the presence of denitrification fronts.
HYDROGEOLOGY JOURNAL
(2023)
Article
Multidisciplinary Sciences
Maciej P. Lewicki, Dominika Lewicka-Szczebak, Grzegorz Skrzypek
Summary: FRAME is a software tool for stable isotope fractionation and mixing evaluation, which allows simultaneous partitioning of sources and determination of fractionation progress. It applies a Markov-Chain Monte Carlo model and provides probability distributions of the calculated results.
Article
Engineering, Environmental
Ruihua Li, Mengsha Guan, Wei Wang
Summary: This study demonstrates that pyrrhotite can effectively remove arsenite and nitrate from groundwater, with the PAD technology providing a simple and cost-effective way for remediation. The PSLAD biofilter achieved good removal efficiency under a hydraulic retention time of 6 hours, showing the potential for practical application in addressing co-contaminated groundwater.
Article
Engineering, Environmental
YeoJin Ju, Dong-Chan Koh, Dong-Hun Kim, Bernhard Mayer, Hong-il Kwon
Summary: This study investigated a riparian aquifer in South Korea that was experiencing declining groundwater levels and elevated nitrate concentrations due to agricultural activities. The main sources of nitrate contamination were identified as manure and sewage, and denitrification was the dominant removal process. The study also found the presence of denitrification and anammox genes in the microbial communities, supporting effective natural nitrate attenuation. Denitrification reduced nitrate flux into the nearby stream, with most of the generated N2 escaping into the atmosphere.
Article
Water Resources
Gerrit Laube, Christian Schmidt, Jan H. Fleckenstein
Summary: This study explored the relationship between nutrient turnover rates in the hyporheic zone and flow dynamics, finding that aerobic and anaerobic turnover rates are influenced differently by conductivity. Additionally, conductivity heterogeneity was shown to decrease nutrient turnover rates in both aerobic and anaerobic reactions.
ADVANCES IN WATER RESOURCES
(2022)
Editorial Material
Water Resources
Stefanie R. Lutz, Pia Ebeling, Andreas Musolff, Tam Van Nguyen, Fanny J. Sarrazin, Kimberly J. Van Meter, Nandita B. Basu, Jan H. Fleckenstein, Sabine Attinger, Rohini Kumar
HYDROLOGICAL PROCESSES
(2022)
Article
Water Resources
Julia L. A. Knapp, Li Li, Andreas Musolff
Summary: This study analyzes long-term low-frequency data from four UK catchments using antecedent catchment wetness as a proxy for lateral hydrologic connectivity. The results demonstrate that solute mobilization mechanisms can vary depending on catchment wetness, as different catchment areas become hydrologically connected to or disconnected from streams. It also shows that flow and streamwater chemistry are mostly decoupled under dry conditions, with solute sources having a stronger impact on mobilization patterns during dry conditions compared to wet conditions.
HYDROLOGICAL PROCESSES
(2022)
Article
Geosciences, Multidisciplinary
Tam Nguyen, Fanny J. Sarrazin, Pia Ebeling, Andreas Musolff, Jan H. Fleckenstein, Rohini Kumar
Summary: Long-term nitrogen transport and retention dynamics in 89 German catchments were studied. Results showed that most nitrogen surplus was removed by denitrification, while the remaining portion was stored in the soil. The study also identified four catchment groups with distinct nitrogen transport and retention dynamics, highlighting the importance of long-term nitrogen accumulation and transport for water quality management.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Soil Science
Vinicius F. Boico, Rene Therrien, Jan H. Fleckenstein, Guilherme Nogueira, Bo V. Iversen, Rasmus J. Petersen
Summary: In this study, a three-dimensional coupled surface-subsurface model was used to simulate a tracer test in a densely tile-drained field, aiming to improve the representation of tracer concentration at the drainage discharge. The model accurately simulated drainage discharge and tracer transport to tile drains, but underestimated the tracer peaks and the late-time tracer mass at the drain outlet. Improvements to the model include the implementation of heterogeneous soil layers and the inclusion of more measured data to reduce uncertainty during calibration.
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL
(2023)
Article
Engineering, Environmental
Franz Dichgans, Jan-Pascal Boos, Pouyan Ahmadi, Sven Frei, Jan H. Fleckenstein
Summary: Despite the limited research on the behavior of microplastics (MP) within fluvial systems, this study investigates the transport and retention of MP using a new numerical modeling approach. The model accurately represents particle transport in turbulent water flow and within the hyporheic zone (HZ) and successfully simulates the transport of MP particles within the HZ. The study provides valuable insights into MP transport processes in rivers and streams and highlights the advantages and limitations of using a fully integrated modeling approach.
Article
Geosciences, Multidisciplinary
Arianna Borriero, Rohini Kumar, Tam V. Nguyen, Jan H. Fleckenstein, Stefanie R. Lutz
Summary: Transit time distributions (TTDs) of streamflow are important for understanding flow and solute transport. This study provides a comprehensive analysis of TTD uncertainty resulting from different model setups. The study finds that the chosen model setup significantly affects the simulation of TTDs and reveals a large uncertainty in the simulated TTDs.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2023)
Article
Geosciences, Multidisciplinary
Thomas Hermans, Pascal Goderniaux, Damien Jougnot, Jan H. Fleckenstein, Philip Brunner, Frederic Nguyen, Niklas Linde, Johan Alexander Huisman, Olivier Bour, Jorge Lopez Alvis, Richard Hoffmann, Andrea Palacios, Anne-Karin Cooke, Alvaro Pardo-Alvarez, Lara Blazevic, Behzad Pouladi, Peleg Haruzi, Alejandro Fernandez Visentini, Guilherme E. H. Nogueira, Joel Tirado-Conde, Majken C. Looms, Meruyert Kenshilikova, Philippe Davy, Tanguy Le Borgne
Summary: This paper discusses the interest and potential for monitoring and characterizing spatial and temporal variability in hydrogeological processes, and proposes a classification of processes and applications at different scales based on high-resolution space-time imaging. The authors call for the validation of 4D imaging techniques at highly instrumented observatories and the harmonization of open databases to share hydrogeological data sets in their 4D components.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2023)
Article
Geosciences, Multidisciplinary
Carolin Winter, Tam V. Nguyen, Andreas Musolff, Stefanie R. Lutz, Michael Rode, Rohini Kumar, Jan H. Fleckenstein
Summary: In 2018-2019, Central Europe experienced an unprecedented 2-year drought with severe impacts on society and ecosystems. This study analyzed the impact of this drought on water quality, finding a drought-induced shift in concentration-discharge relationships and an increase in nitrate loads. The study also revealed that severe droughts can reduce the nitrogen retention capacity of catchments, intensifying nitrate pollution and threatening water quality.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2023)
Article
Geosciences, Multidisciplinary
Jie Yang, Qiaoyu Wang, Ingo Heidbuechel, Chunhui Lu, Yueqing Xie, Andreas Musolff, Jan H. Fleckenstein
Summary: Excess export of nitrate to streams affects ecosystem structure and functions, and the topographic slope has an impact on solute export. Steeper slopes result in more nitrate entering the stream. By modeling a small agricultural catchment in Central Germany, it was found that a smaller topographic slope is associated with a higher young streamflow fraction and lower nitrate concentration in the stream. This has important implications for the management of stream water quality.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)
Article
Chemistry, Analytical
Johanna Schmidtmann, Hassan Elagami, Bejamin S. Gilfedder, Jan H. Fleckenstein, Georg Papastavrou, Ulrich Mansfeld, Stefan Peiffer
Summary: This study found that ferrihydrite can increase the sedimentation rate of microplastics and remove them from the water column. Particularly at acidic pH values, heteroaggregation occurs between ferrihydrite and microplastic particles, leading to their removal from the water.
ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS
(2022)
Article
Geosciences, Multidisciplinary
Guilherme E. H. Nogueira, Christian Schmidt, Daniel Partington, Philip Brunner, Jan H. Fleckenstein
Summary: Riparian zones play an important role in modulating water quality in stream corridors by acting as buffers or facilitating solute turnover. This study used a numerical model and hydraulic mixing cell method to investigate the source composition of water and its spatiotemporal evolution in Selke stream. The results showed the importance of discharge events and event intensity in increasing mixing potential.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2022)