Article
Agricultural Engineering
Dominika Derwis, Joanna Majtacz, Przemys law Kowal, Hussein E. Al-Hazmi, Jun Zhai, Slawomir Ciesielski, Grzegorz Piechota, Jacek Makinia
Summary: The Anammox and sulfate reduction ammonium oxidation processes were compared in two granular sequencing batch reactors operated for 160 days under anammox conditions. The study found that increasing the concentration of sulfate (SO42-) could positively influence the rate of nitrogen (N) removal under anaerobic conditions. It was also discovered that sulfate reduction and anammox occur independently. By increasing the influent sulfate concentration, a higher ammonium utilization rate and sulfate utilization rate were achieved, leading to more efficient treatment of NH4+ and SO42--rich wastewater.
BIORESOURCE TECHNOLOGY
(2023)
Article
Environmental Sciences
Andrew W. Dale, David Clemens, Kirstin Dahnke, Frederike Korth, Scott D. Wankel, Ulrike Schroller-Lomnitz, Klaus Wallmann, Stefan Sommer
Summary: Benthic nitrogen cycling in the Mauritanian upwelling region was studied in 2014, revealing higher NH4+ and PO43- fluxes on the shelf possibly linked to declining bottom water O2 concentrations. The isotopic fractionation of nitrate uptake and elevated (18):(15) ratios on the shelf suggest aerobic ammonium oxidation and nitrite oxidation activities due to oxygen deficiency.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Wokil Bam, Kanchan Maiti, Mark Baskaran
Summary: The distribution and vertical fluxes of particulate organic carbon and other key elements in the Arctic Ocean are mainly influenced by primary productivity, ice cover, and lateral exchange. Seasonal vertical fluxes of particulate organic and inorganic carbon, nitrogen, and biogenic silica were studied using tracers in the western Arctic Basin in 2015. The results highlight the importance of POC and PN fluxes in seasonal vertical transport, with the highest fluxes observed in ice-covered stations in the northern region.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Yuyue Huang, Wei Li, Jie Gao, Fang Wang, Wei Yang, Le Han, Dunmei Lin, Bolin Min, Yue Zhi, Khara Grieger, Jingmei Yao
Summary: This study reveals that microplastics have impacts on ecosystem functions mediated by benthic biota, especially at higher concentrations, indicating adverse effects on microbial nitrogen removal mediated by macroinvertebrates. The findings emphasize the importance of understanding the comprehensive impacts of microplastics on the functioning in freshwater ecosystems.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Biotechnology & Applied Microbiology
Grubba Dominika, Majtacz Joanna, Makinia Jacek
Summary: Sulfate can act as an electron acceptor for ammonium oxidation under anaerobic conditions, known as sulfammox, offering an alternative to nitrite-dependent anammox. This process shows promising removal efficiencies for both NH4+ and SO42- in various wastewater systems, especially in industrial settings with high nitrogen compound and sulfate content.
ENVIRONMENTAL TECHNOLOGY & INNOVATION
(2021)
Article
Multidisciplinary Sciences
Katja Laufer-Meiser, Alexander B. Michaud, Markus Maisch, James M. Byrne, Andreas Kappler, Molly O. Patterson, Hans Roy, Bo Barker Jorgensen
Summary: The Arctic has the highest warming rates on Earth, and the glacial fjord ecosystems are sensitive to this warming, impacting iron cycling and bioavailability. Glacial retreat may reduce the flux of iron to coastal marine ecosystems, affecting biogeochemical processes. Further research is needed to fully understand the impacts of a melting Arctic on marine ecosystems.
NATURE COMMUNICATIONS
(2021)
Article
Engineering, Environmental
Jie Gao, Yue Zhi, Yuyue Huang, Sijie Shi, Qiujun Tan, Chengcheng Wang, Le Han, Jingmei Yao
Summary: Benthic macroinvertebrates, especially Propsilocerus akamusi, have a significant impact on anammox and nitrogen removal processes in freshwater ecosystems by increasing the abundance and potential rate of anammox bacteria.
Article
Green & Sustainable Science & Technology
Zixuan Liang, Juan Shi, Wan Yang, Lingling Dai, Xiaohu Dai
Summary: The addition of PFS improved the spatial structure of microbial aggregations and promoted denitrification, leading to increased nitrogen removal efficiency and oxygen savings. Two possible feammox bacteria were selected with the use of PFS.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Environmental Sciences
Haoming Xu, Guodong Song, Siqi Yang, Ruosi Zhu, Guiling Zhang, Sumei Liu
Summary: This study investigates benthic nitrogen cycling in the deep ocean of the Kuroshio Extension region and highlights nitrification as the predominant process and anammox as the dominant N-loss process. The findings suggest temperature and ammonium are limiting factors for deep-ocean benthic N-loss. Additionally, there is a tight coupling relationship between pelagic primary production and the benthic nitrogen cycle in the study area.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Geosciences, Multidisciplinary
Lisa C. Herbert, Alexander B. Michaud, Katja Laufer-Meiser, Clara J. M. Hoppe, Qingzhi Zhu, Robert C. Aller, Bo Barker Jorgensen, Laura M. Wehrmann
Summary: Glaciated fjords are dynamic systems influenced by seasonal changes and spatial gradients, impacting organic carbon mineralization and nutrient fluxes. Seasonal variations and increased benthic nutrient sources may lead to changes in iron and sulfur cycling.
JOURNAL OF MARINE SYSTEMS
(2022)
Article
Environmental Sciences
Sanni L. Aalto, Suvi Suurnakki, Mathis von Ahnen, Marja Tiirola, Per Bovbjerg Pedersen
Summary: Woodchip bioreactors are effective in removing nitrate from aquaculture effluents, with microbial communities including sulfate reducing bacteria (SRB) and sulfate oxidizing bacteria (SOB) playing crucial roles. The conditions within the bioreactors shape the microbial communities, with similar design and operational settings leading to similar functions. Autotrophic denitrifiers can significantly contribute to H2S consumption and nitrate removal in woodchip bioreactors, improving their overall environmental benefit.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Environmental Sciences
Bo Wang, Xin Qiao, Feng Hou, Tao Liu, Hongtao Pang, Yuanyuan Guo, Jianhua Guo, Yongzhen Peng
Summary: A pilot-scale system integrating Partial Nitritation and simultaneous Anammox, Denitrification and Sludge Fermentation (PN + ADSF) process was developed to treat real municipal wastewater. The system achieved desirable total inorganic nitrogen (TIN) concentrations in the effluent and sludge reduction efficiency simultaneously. The characterization on microbial communities revealed the dominant functional bacteria for anammox and denitrification.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Green & Sustainable Science & Technology
Manping Zhang, Jung-Chen Huang, Shanshan Sun, Muhammad Muneeb Ur Rehman, Shengbing He, Weili Zhou
Summary: The study found that denitrification is the main mechanism of nitrate reduction in constructed wetlands, with the majority of nitrogen gas produced through this process. The rates of three microbial nitrate reduction processes were significantly higher in the PA wetland than in the NP wetland. Additionally, nitrate plays a crucial role in the competition between DNRA and denitrification, while nitrite regulates anammox.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Microbiology
Samantha G. Fortin, Bongkeun Song, Iris C. Anderson
Summary: This study found that denitrification is the primary process for nitrogen removal in the York River Estuary, while DNRA is the main process for nitrogen retention. Denitrification rates are strongly correlated with concentrations of organic matter, nitrate and chlorophyll a, while DNRA rates are best correlated with the relative abundance of specific bacterial families carrying the nrfA gene.
FEMS MICROBIOLOGY ECOLOGY
(2021)
Article
Engineering, Environmental
Qingkun Wang, Matthew James Rogers, Sir Sing Ng, Jianzhong He
Summary: The study sheds light on the significance of anammox activity and its association with sulfide-driven dissimilatory nitrate reduction to ammonium (DNRA) in tropical wetlands. Microbial community analysis revealed a diverse array of anammox bacteria, and correlation analysis suggested potential syntrophic interactions among sulfate-reducing, sulfide-driven DNRA, and anammox bacterial populations.
Article
Biodiversity Conservation
Mads Reinholdt Jensen, Signe Hogslund, Steen Wilhelm Knudsen, Julius Nielsen, Peter Rask Moller, Soren Rysgaard, Philip Francis Thomsen
Summary: The study aims to investigate the transition in fish and marine mammal communities from South to Northeast Greenland using environmental DNA (eDNA). The results demonstrate a clear shift in biological communities from south to northeast, with different fish and mammal species dominating each region. The study highlights the potential of eDNA sampling in detecting latitudinal changes in marine biological communities and its feasibility in remote areas as climate change progresses.
DIVERSITY AND DISTRIBUTIONS
(2023)
Article
Environmental Sciences
Henry C. Henson, Johnna M. Holding, Lorenz Meire, Soren Rysgaard, Colin A. Stedmon, Alice Stuart-Lee, Jorgen Bendtsen, Mikael Sejr
Summary: Greenland's fjords and coastal waters are highly productive and sustain important fisheries, but retreating glaciers and increasing meltwater are changing fjord circulation and biogeochemistry, potentially threatening future productivity. The freshening of Greenland fjords caused by unprecedented melting of the Greenland Ice Sheet may alter carbonate chemistry in coastal waters, impacting CO2 uptake and causing acidification-related biological consequences. However, there have been few studies on the current acidification state in Greenland coastal waters.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Microbiology
Clemens Schauberger, David Seki, Elise M. M. Cutts, Ronnie N. N. Glud, Bo Thamdrup
Summary: Microbial communities in marine sediments are highly diverse, and their composition gradually changes with sediment depth due to the abrupt changing selective pressures across the discrete boundaries between redox zones. Dispersal limitation affects microbial communities, and the relative contributions of different processes leading to this compositional gradient are still unknown. This study applied ecological statistical frameworks to investigate the links between biogeochemistry, burial, and microbial community assembly processes in Atacama Trench sediments.
ENVIRONMENTAL MICROBIOLOGY
(2023)
Article
Engineering, Environmental
Ioannis D. Kampouris, Grundger Friederike Grundger, Jan H. Christensen, CharlesW. Greer, Kasper Urup Kjeldsen, Wieter Boone, Lorenz Meire, Soren Rysgaard, Leendert Vergeynst
Summary: The growth of oil-degrading bacteria in the Arctic marine environment is limited by the harsh conditions such as nutrient limitations and sub-zero temperatures. The study found that the variance between epipelagic and mesopelagic zones could limit the growth of oil-degrading bacteria and result in lower oil biodegradation rates in the epipelagic zone. The environmental conditions in the epipelagic zone limited oil biodegradation performance by limiting bacterial growth.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Limnology
Xinxin Li, Xin Zhao, Hongyue Dang, Chuanlun Zhang, Igor Fernandez-Urruzola, Zhiqiang Liu, Frank Wenzhoefer, Ronnie N. Glud
Summary: This study focuses on the study of Hadal sediments in the Atacama Trench in the Pacific Ocean. It found that Hadal sediments are important carbon deposition centers and have intensified microbial activity. The sources and turnover of hadopelagic organic carbon and its linkages to microbial activities have not been studied. The research also found that particulate organic carbon, dark carbon fixation, and size-fractionated microbial community respiration proxy attenuate rapidly with increasing depth in the water, but remain stable in bathypelagic and abyssopelagic waters. High variability in organic carbon sources and microbial activities was observed in the hadopelagic trench.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Ecology
Emma H. Boldreel, Karl M. Attard, Kasper Hancke, Ronnie N. Glud
Summary: This study investigates the benthic degradation of kelp detritus in defaunated mesocosms and explores the factors that affect the degradation dynamics. The results show that the degradation rates of kelp increase linearly with the amount of kelp added, and lower ambient temperature reduces the benthic mineralization rate. The study highlights the importance of considering key variables, such as kelp quantity and temperature, when assessing the environmental implications of seaweed farming.
MARINE ECOLOGY PROGRESS SERIES
(2023)
Review
Oceanography
Christian Mohn, Jorgen L. S. Hansen, Marina Carreiro-Silva, Stuart A. Cunningham, Evert de Froe, Carlos Dominguez-Carrio, Stefan Gary, Ronnie N. Glud, Cordula Goke, Clare Johnson, Telmo Morato, Eva Friis Moller, Lorenzo Rovelli, Kirstin Schulzi, Karline Soetaert, Anna van der Kaaden, Dick van Oevelen
Summary: Cold-water corals (CWCs) thrive in areas with complex and rough topography, but little is known about how basin-scale changes in the ocean climate affect their growth. In this study, high-resolution hydrodynamic models were used to investigate the impact of variations in basin-scale currents on local hydrodynamics and CWC communities. It was found that the variability of near-bottom currents and water mass properties at different AMOC states strongly influenced the CWC distribution. The kinetic energy dissipation rate was proposed as a mechanistic descriptor of CWC presence, providing insight into the hydrodynamics driving organic matter supply to these communities.
PROGRESS IN OCEANOGRAPHY
(2023)
Article
Environmental Sciences
Daniel F. Carlson, Antoni Vivo-Pons, Urs A. Treier, Eva Matzler, Lorenz Meire, Mikael Sejr, Dorte Krause-Jensen
Summary: Changes in the distribution of coastal macrophytes in Greenland and elsewhere in the Arctic are difficult to quantify due to limited access and monitoring capabilities. The use of satellite imagery, specifically Sentinel-2, is impacted by optically complex environments and a scarcity of supporting data. Three hypotheses are tested to understand the factors influencing the spatial distribution of intertidal macrophytes in Greenland's fjord systems. The study highlights the role of icebergs and turbidity in shaping macrophyte distribution and suggests that the retreat of marine-terminating glaciers could lead to an expansion of macrophyte cover.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Multidisciplinary Sciences
Anna Sobek, Sebastian Abel, Hamed Sanei, Stefano Bonaglia, Zhe Li, Gisela Horlitz, Arka Rudra, Kazumasa Oguri, Ronnie N. N. Glud
Summary: Persistent organic pollutants (POPs) are found in hadal trench sediment in the Atacama trench at depths down to 8085 m. High turnover of organic matter in the trench contributes to elevated contaminant concentrations in this extreme and remote place.
NATURE COMMUNICATIONS
(2023)
Article
Oceanography
T. M. Burgers, L. A. Miller, S. Rysgaard, J. Mortensen, B. Else, J. -E Tremblay, T. Papakyriakou
Summary: In August 2014, we characterized the physico-chemical properties of water masses entering Nares Strait. We used an extended OMP analysis to estimate mixing fractions and determine the role of physical and biological processes in the distribution of DIC. Our observations include evidence of Siberian shelf waters and diluted Pacific-origin upper halocline layer entering Nares Strait. These mixed-origin water masses drive phytoplankton bloom in Kane Basin, leading to decreased surface pCO(2) concentrations. The positioning of the Transpolar Drift and the balance of Atlantic and Pacific water delivered to Nares Strait play an important role in regional biological productivity and carbon uptake.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Limnology
Adele Maciute, Oleksandr Holovachov, Ronnie N. Glud, Elias Broman, Peter Berg, Francisco J. A. Nascimento, Stefano Bonaglia
Summary: Meiofauna, the smallest organisms on the ocean floor, have a significant impact on benthic oxygen demand. However, their contribution has been understudied. Our study used a novel approach to measure the respiration rates of 10 different meiofauna groups in natural sediment conditions. We found that nematodes and foraminifera are the most important contributors to sediment oxygen uptake and should be considered in benthic oxygen and carbon cycle estimations.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Limnology
Philipp A. Nauer, Adam J. Kessler, Puspitaningsih Hall, Maria Elena Popa, Sophie ten Hietbrink, Tess Hutchinson, Wei Wen Wong, Karl Attard, Ronnie N. Glud, Chris Greening, Perran L. M. Cook
Summary: Dihydrogen (H-2) accumulation and decoupling of fermentation and sulfate reduction were observed in permeable marine sediments during a coral spawning event, suggesting transient decoupling of microbial processes. Laboratory experiments showed that oxygen exposure had little effect on H-2 accumulation, while physical disturbance led to transient H-2 accumulation and release of dissolved organic carbon. The highly dynamic nature of permeable sediments allows for rapid but transient decoupling of fermentation and respiration, leading to high H-2 levels.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Geosciences, Multidisciplinary
Lorenz Meire, Maria Lund Paulsen, Patrick Meire, Soren Rysgaard, Mark James Hopwood, Mikael Kristian Sejr, Alice Stuart-Lee, Koen Sabbe, Willem Stock, John Mortensen
Summary: Glacier retreat in Greenland alters the primary productivity, ecosystem structure, and functioning of downstream fjord ecosystems. Monthly sampling in two fjords in southwest Greenland in 2016 revealed that subglacial discharge from marine-terminating glaciers sustains high phytoplankton productivity dominated by diatoms and grazed by larger mesozooplankton throughout summer. On the other hand, melting of land-terminating glaciers results in a fjord ecosystem dominated by bacteria, picophytoplankton, and smaller zooplankton, with only one-third of the annual productivity and half the CO2 uptake compared to the fjord downstream from marine-terminating glaciers.
Article
Soil Science
Pengzhi Zhao, Daniel J. Fallu, Ben R. Pears, Camille Allonsius, Jonas J. Lembrechts, Stijn Van de Vondel, Filip J. R. Meysman, Sara Cucchiaro, Paolo Tarolli, Pu Shi, Johan Six, Antony G. Brown, Bas van Wesemael, Kristof Van Oost
Summary: Oxyhydroxides, soil texture, and soil organic carbon (SOC) fractions are important for organic carbon cycling in soils. Traditional methods to determine these properties are time-consuming and expensive, but visible near infrared (Vis-NIR) and mid-infrared (MIR) spectroscopy offer a promising alternative. This study demonstrates that combining soil infrared spectroscopy with compositional data analysis allows for cost-effective and reliable quantification of these properties, providing a practical opportunity to assess the role of SOC in global carbon cycling.
SOIL & TILLAGE RESEARCH
(2023)
Article
Microbiology
Jeanine S. Geelhoed, Casper A. Thorup, Jesper J. Bjerg, Lars Schreiber, Lars Peter Nielsen, Andreas Schramm, Filip J. R. Meysman, Ian P. G. Marshall
Summary: In this study, we identified a novel species of marine cable bacteria with a large diameter, named Candidatus Electrothrix gigas. The genomes of this species contain a gene encoding a novel actin-like protein (Bbp) that is also found in other giant bacteria. This suggests that there may be a genetic basis for large cell size. The Bbp protein may have a structural role in the cell or potentially facilitate intracellular transport.
MICROBIOLOGY SPECTRUM
(2023)