Article
Environmental Sciences
Yan Huang, Soonmo An
Summary: This study examined the effects of seasonal hypoxia on nitrogen transformations at the sediment-water interface in Jinhae Bay. The results showed that denitrification increased, anammox ceased, and DNRA decreased during hypoxia. Sediments acted as a sink for nitrate during hypoxia. The dominance of DNRA may contribute to eutrophication and seasonal hypoxia in this system.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Limnology
Astrid Hylen, Stefano Bonaglia, Elizabeth Robertson, Ugo Marzocchi, Mikhail Kononets, Per O. J. Hall
Summary: Coastal and shelf sediments play a crucial role in the global nitrogen cycle, but ongoing deoxygenation in many coastal areas can hinder the removal of fixed nitrogen. While natural reoxygenation can reinstate anoxic sediments as efficient sites for fixed nitrogen removal, it may not lead to efficient sedimentary removal of fixed nitrogen at newly oxygenated sites.
LIMNOLOGY AND OCEANOGRAPHY
(2022)
Article
Soil Science
Yuxuan Wan, Qing Du, Yue Wu, Ruixiang Li, Xuejun Yan, Nan Li, Xin Wang
Summary: Large amounts of nitrogen fertilized to food production are lost via denitrification and leaching. Dissimilatory nitrate reduction to ammonium (DNRA) is a bioprocess competing with denitrification, and it conserves bioavailable nitrogen in soil ecosystems. Our results found a sustainable way of nitrogen retention in soils, and have broader implications for understanding nitrogen turnover in ecosystems.
SOIL BIOLOGY & BIOCHEMISTRY
(2023)
Article
Environmental Sciences
Feng Sun, Qinghui Deng, Xiaowen Li, Mengjuan Tang, Xufa Ma, Xiuyun Cao, Yiyong Zhou, Chunlei Song
Summary: The study found that high organic carbon content in matrix facilitated dissimilatory nitrate reduction to ammonium (DNRA) over denitrification (DEN), while low organic carbon content promoted DEN. It was also observed that using corn cob as OC source in biofilters was more effective than bagasse due to slow and continuous release of organic carbon. Choosing suitable OC source and regulating its dosage are crucial for enhancing nitrate removal and reducing ammonium accumulation in biofilters.
Article
Biotechnology & Applied Microbiology
Peike Gao, Yu Gao, Hongbo Wang, Ting Ma, Ji-Dong Gu
Summary: This study identifies the presence of anammox bacteria in oil reservoirs and suggests that they are more easily detected in the downhole of water-injection wells. These bacteria, along with other bacteria, participate in the nitrogen cycle in oil reservoirs and potentially reduce externally injected nitrate through the production of N2O and N2. This research improves our understanding of anammox bacteria detection and highlights their roles in the nitrogen cycle in oil reservoirs.
INTERNATIONAL BIODETERIORATION & BIODEGRADATION
(2023)
Article
Environmental Sciences
Rauno Lust, Jaak Nerut, Sharvari S. Gadegaonkar, Kuno Kasak, Mikk Espenberg, Triinu Visnapuu, Uelo Mander
Summary: Microbial electrosynthesis is a promising solution for removing low concentrations of nitrate from water. The study found that the design of a single-chamber reactor saves on construction costs and provides more stable pH levels in the solution. The optimal electrode potential achieved the highest Faradaic efficiency and nitrate removal rate. Additionally, the process was driven by denitrification, and the microbial electrosynthesis reactor can be effectively used to purify water sources when adding organic compounds as electron donors is not feasible.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2022)
Article
Engineering, Civil
Ya Wu
Summary: High levels of ammonium in the coastal acidic groundwater of Beihai, Southern China pose a threat to surface ecosystems and water supplies. A study was conducted using hydrochemical and isotopic analysis to investigate the occurrence of ammonium and its genesis. The findings suggest that dissimilatory nitrate reduction to ammonium plays a critical role in the enrichment of ammonium concentrations in groundwater.
JOURNAL OF HYDROLOGY
(2022)
Article
Soil Science
Xin Fang, Zhishu Yang, Jiangang Han
Summary: This study investigated the effects of different vegetation belts and seasonal changes on DNF, DNRA, and bacterial community structure in a coastal wetland. The results showed that DNRA was the dominant process in NO3- reduction in this wetland, and the DNRA/DNF ratios were positively correlated with soil NO3- concentrations.
APPLIED SOIL ECOLOGY
(2022)
Article
Environmental Sciences
Shreeram Inamdar, Marc Peipoch, Arthur J. Gold, Evan Lewis, Johanna Hripto, Melissa Sherman, Kelly Addy, Dorothy Merritts, Jinjun Kan, Peter M. Groffman, Robert Walter, Tara L. E. Trammell
Summary: Milldams and their legacies have significant impacts on fluvial processes and geomorphology, but their effects on riparian nitrogen processing are less understood. The potential effects of existing and breached milldams on riparian nitrogen cycling are uncertain and require further investigation.
ENVIRONMENTAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Xiaolong Yao, Zhonghua Zhao, Jianjun Wang, Qiqi Ding, Minglei Ren, Ismael Aaron Kimirei, Lu Zhang
Summary: The nitrogen transformation in East African lakes is mainly driven by benthic organic matter properties and water column phosphate concentrations, and the sediment nitrogen supply and loss can be improved by considering sediment organic matter properties.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Agricultural Engineering
Shiyang Zhang, Longqu Xiao, Zhiwei Tang, Xiangling Zhang, Zhi Wang
Summary: This study investigated the fluctuating profiles of physicochemical and microbial characterizations along different filling heights of continuously up-flow solid-phase denitrification columns packed with PCL. It was found that both the PCL filling area and non-filling area significantly contributed to treatment performance, with denitrification mainly occurring near the bottom of the filling column. Nitrate showed high removal rates, while nitrite and ammonium displayed weak accumulation in final effluents.
BIORESOURCE TECHNOLOGY
(2022)
Article
Limnology
Guodong Song, Sumei Liu, Jing Zhang, Zhuoyi Zhu, Guiling Zhang, Hannah K. Marchant, Marcel M. M. Kuypers, Gaute Lavik
Summary: Decreases in bottom water oxygen concentration lead to reductions in sediment oxygen uptake and penetration depth, while denitrification rates increase. Nitrate and ammonium fluxes show complex behavior under hypoxic conditions. Changes in benthic nutrient cycling under hypoxia enhance the retention of nitrogen, exacerbating oxygen deficiency.
LIMNOLOGY AND OCEANOGRAPHY
(2021)
Article
Microbiology
Jeseth Delgado Vela, Laura A. Bristow, Hannah K. Marchant, Nancy G. Love, Gregory J. Dick
Summary: The increase of sulfide concentrations in a bioreactor fed with methane and ammonium led to a decrease in nitrite oxidation rates and an increase in ammonia oxidation rates, along with changes in the denitrifying community and an increase in nitrous oxide production. This shift in microbial relationships and processes highlights the intricate and interconnected nature of microbial interactions in elemental cycling.
ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Environmental Sciences
Xiaoling Li, Jianqiang Zhao, Yuhao Zhang, Jiaojie He, Kaili Ma, Chunshuang Liu
Summary: This study found that the proportion of DNRA increases in high-electron systems, particularly in organic-rich or sulfide-rich systems, indicating that excess electron donors favor DNRA. Additionally, a higher reductive environment also facilitates DNRA. 16S rRNA gene sequencing analysis revealed different participants involved in the DNRA process in organic-rich and sulfide-rich systems.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Microbiology
Shih-Yao Lin, Asif Hameed, Chia-Fang Tsai, Chiu-Chung Young
Summary: A Gram-stain-negative bacterium named Vineibacter terrae gen. nov., sp. nov. was isolated from vineyard soil in Taiwan. This bacterium is aerobic, non-motile, and capable of reducing nitrate, with optimal growth conditions at 30 degrees C and pH 7, belonging to the family Rhodospirillaceae.
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY
(2021)
Article
Geochemistry & Geophysics
Guang-Chao Zhuang, Andrew Montgomery, Samantha B. Joye
GEOCHIMICA ET COSMOCHIMICA ACTA
(2019)
Article
Environmental Sciences
Guang-Chao Zhuang, Tito D. Pena-Montenegro, Andrew Montgomery, Joseph P. Montoya, Samantha B. Joye
GLOBAL BIOGEOCHEMICAL CYCLES
(2019)
Article
Limnology
Mary Katherine Rogener, Rachel E. Sipler, Kimberley S. Hunter, Deborah A. Bronk, Samantha B. Joye
LIMNOLOGY AND OCEANOGRAPHY
(2020)
Article
Ecology
Adrien Assie, Nikolaus Leisch, Dimitri Meier, Harald Gruber-Vodicka, Halina E. Tegetmeyer, Anke Meyerdierks, Manuel Kleiner, Tjorven Hinzke, Samantha Joye, Matthew Saxton, Nicole Dubilier, Jillian M. Petersen
Article
Limnology
Charles A. Schutte, Vladimir A. Samarkin, Brian Peters, Michael T. Madigan, Marshall Bowles, Rachael Morgan-Kiss, Karen Casciotti, Samantha Joye
LIMNOLOGY AND OCEANOGRAPHY
(2020)
Article
Multidisciplinary Sciences
Igal Berenshtein, Claire B. Paris, Natalie Perlin, Matthew M. Alloy, Samantha B. Joye, Steve Murawski
Article
Microbiology
Lei Xu, Guang-Chao Zhuang, Andrew Montgomery, Qianyong Liang, Samantha B. Joye, Fengping Wang
Summary: A cryptic methane cycle was found in sulfate-reducing sediments from the continental shelf of the northern South China Sea, driven by methyl-compounds and potentially fueling AOM. Methanogenesis primarily occurs through the methylotrophic pathway, and AOM rates are supported by alternative electron acceptors in this environment.
ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Environmental Sciences
C. A. Schutte, W. S. Moore, A. M. Wilson, S. B. Joye
GLOBAL BIOGEOCHEMICAL CYCLES
(2020)
Article
Environmental Sciences
Camaron George, Willard S. Moore, Scott M. White, Erin Smoak, Samantha B. Joye, Andrew Leier, Alicia M. Wilson
WATER RESOURCES RESEARCH
(2020)
Article
Engineering, Marine
Saskia Rughoft, Anjela L. Vogel, Samantha B. Joye, Tony Gutierrez, Sara Kleindienst
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2020)
Article
Environmental Sciences
Mary Katherine Rogener, Kimberley S. Hunter, Nancy N. Rabalais, Brian J. Roberts, Annalisa Bracco, Frank J. Stewart, Samantha B. Joye
Summary: Anthropogenic nutrient inputs have led to eutrophication and hypoxia in coastal areas globally, with the Louisiana shelf hosting the world's second largest anthropogenic coastal hypoxic zone. High rates of pelagic denitrification and methane oxidation were observed in hypoxic waters characterized by high concentrations of nitrous oxide and methane. However, denitrification was found to potentially remove a significant portion of DIN input from the Mississippi River, while methane oxidation did not effectively remove methane, which escaped into the atmosphere. The microbial removal capacity for nitrate/nitrite and methane in this ecosystem was regulated by physiochemical dynamics, with bacteria unable to keep up with the nutrient inputs.
Article
Limnology
Matthew A. Saxton, Vladimir A. Samarkin, Michael T. Madigan, Marshall W. Bowles, William Matthew Sattley, Charles A. Schutte, Samantha B. Joye
Summary: Documenting anaerobic microbial metabolisms in hypersaline perennially ice-covered lakes in Antarctica provides insights into the environmental limits of life and potential novel biogeochemical mechanisms. Researchers assessed rates of various microbial processes in Lake Vanda, Antarctica, and found an active microbial community uniquely adapted to survive in extreme environments.
LIMNOLOGY AND OCEANOGRAPHY
(2021)
Article
Microbiology
Angelina G. Angelova, Barbara Berx, Eileen Bresnan, Samantha B. Joye, Andrew Free, Tony Gutierrez
Summary: This study assessed the spatiotemporal variability of baseline bacterioplankton community composition in the Faroe-Shetland Channel (FSC), showing significant differences in bacterioplankton communities across water samples of contrasting origin and depth. Higher-than-anticipated abundances of known hydrocarbon-degrading bacteria were observed in water masses originating in the Nordic Seas, suggesting an unconfirmed source of oil input. The response of these organisms in the event of an oil spill is hindered by the low temperatures and nutrient levels typical for the FSC.
Article
Environmental Sciences
Nathaniel B. Weston, Elise Rodriguez, Brian Donnelly, Elena Solohin, Kristen Jezycki, Sandra Demberger, Lori A. Sutter, James T. Morris, Scott C. Neubauer, Christopher B. Craft
Summary: The stability of coastal wetlands is influenced by sea level, plant primary production, sediment supply, and wetland vertical accretion. Human activities have impacted sediment delivery to coastal areas along the U.S East Coast. Wetlands in areas with low sediment supply may struggle to keep pace with rising sea levels. This study shows that the vertical accretion and carbon accumulation in tidal wetlands along the U.S East Coast can be explained by relative sea level rise, sediment concentration in rivers, and coastal temperature.
Article
Biochemistry & Molecular Biology
Lauren Sage, Olivia Bassetti, Erin Johnson, Kabindra Shakya, Nathaniel Weston
Summary: Urban and ex-urban residents are increasingly using community gardens to supplement their diets, engage with neighbors, and learn new skills. However, the soils in these gardens can pose a threat to human health if contaminated with metals. This study analyzed the heavy metal content in the soils of 20 Philadelphia-region community gardens and the produce from 6 gardens, revealing that a significant portion of both soil and produce samples exceeded safe lead levels.
ENVIRONMENTAL POLLUTANTS AND BIOAVAILABILITY
(2023)