Article
Engineering, Environmental
Junkai Gao, Guanglong Liu, Xiaowen Li, Mengjuan Tang, Xiuyun Cao, Yiyong Zhou, Chunlei Song
Summary: This study investigated the impact of organic carbon quantity and composition on nitrate reduction pathways in two basins of Lake Chaohu in Hefei City, China. It was found that the serious algal bloom in the west basin resulted in higher organic carbon accumulation and nitrate deficiency, leading to a high C/NO3--N ratio. This triggered dissimilatory nitrate reduction to ammonium (DNRA) and specific bacterial communities played a role in this process.
Article
Environmental Sciences
Dongyao Sun, Jiafang Huang, Min Luo, Cheng Chen, Xue Lan, Weifang Hu
Summary: Intensive aquaculture in estuaries and coasts has led to ecological and environmental problems. Among nitrogen transformation pathways, dissimilatory nitrate reduction plays a crucial role in regulating reactive nitrogen. This study investigated the three sediment processes of nitrate reduction and found that denitrification was the dominant pathway. Environmental factors such as C and N substrates and salinity significantly influenced nitrate reduction. The nitrogen losses from denitrification and anaerobic ammonium oxidation were substantial, indicating the importance of coastal reclamation in nitrogen removal.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Paraskevi Mara, Virginia P. Edgcomb, Taylor R. Sehein, David Beaudoin, Chuck Martinsen, Christina Lovely, Bridget Belcher, Rebecca Cox, Meghan Curran, Claire Farnan, Peter Giannini, Sarah Lott, Kyle Paquette, Anna Pinckney, Natalie Schafer, Tonna-Marie Surgeon-Rogers, Daniel R. Rogers
Summary: The study found that oyster aquaculture plays a positive role in the removal of nitrogen from sediments, but different farming methods show variations in gene expression related to nitrogen cycling and nitrogen gas flux. Particularly, nitrogen retention process is significantly enhanced, especially under the bottom cages.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Environmental Sciences
Binjie Zhao, Xinshuai Li, Yang Wang, Xiang Tan, Wenhua Qi, Hongran Li, Junwei Wei, Yong You, Wenjun Shi, Quanfa Zhang
Summary: The study investigated dissimilatory nitrate reduction rates in sediments of two subtropical rivers in China, revealing varying contributions of denitrification, anammox, and DNRA in different seasons and under different levels of human disturbance. The rates were correlated with environmental factors, highlighting the importance of understanding these processes for sustaining the ecohealth of river ecosystems.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Environmental Sciences
Yunmeng Pang, Jianlong Wang, Shengjie Li, Guodong Ji
Summary: This study revealed that the addition of sulfide (S2-) enhanced the coupling of denitrification with sulfide oxidation, leading to a shift in nitrate reduction pathways in freshwater lake sediments. The enrichment of Thiobacillus, a sulfide-oxidizing denitrifier, was found to play a key role in driving sulfide-driven denitrification, with differences observed in lakes with varying inherent organic carbon and sulfate levels. Additionally, internal sulfate release was seen to promote cooperation between sulfide-oxidizing denitrifiers and sulfate reducers in freshwater environments.
ENVIRONMENTAL POLLUTION
(2021)
Article
Environmental Sciences
Mengjuan Tang, Qinghui Deng, Xiuyun Cao, Yiyong Zhou, Qingye Sun, Chunlei Song
Summary: This study found that iron-rich clay and Phoslock agent can effectively promote phosphorus immobilization in sediments and reduce phosphorus release risk by adding an oxidizing agent. The mixture of sugarcane detritus and IR clay impacted denitrification and DNRA, requiring control of the SU dosage to prevent excessive DNRA. The use of P sorbent and organic C combined with oxidizing agents is recommended for sediment remediation to enhance P adsorption, provide electron donors for denitrification, and avoid anoxic conditions.
JOURNAL OF SOILS AND SEDIMENTS
(2021)
Article
Engineering, Environmental
Xingyu Jiang, Changqing Liu, Yang Hu, Keqiang Shao, Xiangming Tang, Lu Zhang, Guang Gao, Boqiang Qin
Summary: Salinization and nitrogen pollution caused by climate change are significant threats to inland lakes. This study conducted field observations and experiments in East Asian lakes to explore the response of key nitrogen cycle processes to climate-induced changes in salinity. The findings showed that increased salinity inhibited denitrification but had insignificant or positive effects on nitrate reduction to ammonium. Inland lakes act as long-term integrators of climatic conditions, and climate-induced salinization and drying can have negative impacts on nitrogen pollution in these lakes.
Article
Marine & Freshwater Biology
Sanni L. Aalto, Eero Asmala, Tom Jilbert, Susanna Hietanen
Summary: Coastal environments play a crucial role in regulating the transfer of nitrogen from land to sea, with variations in nitrate reduction processes between estuary and offshore archipelago environments in the Baltic Sea. The balance between denitrification and DNRA processes is influenced by the ratio of nitrate to autochthonous organic carbon, impacting the release of nitrous oxide and efficiency of nitrogen recycling in different coastal areas.
ESTUARINE COASTAL AND SHELF SCIENCE
(2021)
Article
Geosciences, Multidisciplinary
Fangjuan Huang, Xianbiao Lin, Weifang Hu, Fang Zeng, Lei He, Kedong Yin
Summary: This study investigates the microbial nitrogen cycling processes in surface sediments of the Pearl River Estuary, revealing higher rates and gene abundance in the outer estuary. Denitrification was found to be the dominant pathway contributing to nitrate reduction in the study area, suggesting the sediment's significant role in mitigating and controlling nitrogen pollution. The study also highlights the complexity of nitrogen cycling processes in controlling the N budget in the Pearl River Estuary and improving the understanding of these processes in estuarine and coastal ecosystems.
Article
Environmental Sciences
Zhenzhen Teng, Xianbiao Lin
Summary: This study investigates the dynamics of sediment NOx- reduction processes in mangroves of different ages and finds that organic matter and microbial abundances are the main factors controlling nitrogen loss and retention. The conservation and restoration of mangroves can increase sediment nitrogen retention, providing more nutrients for mangrove and microorganism growth.
SCIENCE OF THE TOTAL ENVIRONMENT
(2024)
Article
Environmental Sciences
Helena Jantti, Sanni L. Aalto, Hans W. Paer
Summary: This study conducted in the Neuse River Estuary in North Carolina, USA, found that DNRA dominated over denitrification in this hypoxic estuary, with no clear correlation between potential nitrate reduction rates, salinity, or dissolved oxygen levels. Prolonged hypoxia led to a loss of denitrification capacity and increased nitrous oxide formation in sediments. Additions of hydrogen sulfide stimulated DNRA while additions of ferrous iron stimulated nitrate consumption, but the exact end product was unclear.
ESTUARIES AND COASTS
(2021)
Article
Environmental Sciences
Shengjie Li, Yinhao Liao, Yunmeng Pang, Xiaoli Dong, Marc Strous, Guodong Ji
Summary: In long-term microcosm incubations, the addition of nitrate and Fe(II) can stimulate denitrification and dissimilatory nitrate reduction to ammonia (DNRA), leading to a higher nitrate reduction rate. Iron (II) contributes to the production of lepidocrocite, promoting the process of nitrate reduction.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Derek G. Tollette, Behzad Mortazavi, Corianne Tatariw, Nikaela Flournoy, Patricia A. Sobecky
Summary: Coastal marshes play a crucial role in removing excess nitrogen from coastal waters. This study investigates the impact of water accommodated fraction (WAF) of oil on nitrogen cycling capacity in marsh sediments. The results show that oil contamination alters the microbial community structure and affects nitrogen cycling processes in salt marsh sediments.
WATER AIR AND SOIL POLLUTION
(2022)
Article
Environmental Sciences
Xiong Xiong, Tyler H. Tappenbeck, Chenxi Wu, James J. Elser
Summary: The study assessed the presence of microplastics in Flathead Lake and found that the concentrations were similar to other lakes in less populated areas worldwide. The research also suggested that precipitation might enhance the deposition of microplastics.
ENVIRONMENTAL POLLUTION
(2022)
Article
Environmental Sciences
Song Li, Robert R. Twilley
Summary: Nitrate enrichment in rivers may alter nitrogen cycling in coastal ecosystems, with direct denitrification being a dominant process in inundated sediments. The importance of denitrification, DNRA, and anammox varied with organic matter concentrations, indicating the complex dynamics of nitrogen processing in coastal deltaic floodplains.
ESTUARIES AND COASTS
(2021)
Editorial Material
Microbiology
Sara Hallin
ENVIRONMENTAL MICROBIOLOGY
(2023)
Article
Marine & Freshwater Biology
Pau Gimenez-Grau, Lluis Camarero, Carlos Palacin-Lizarbe, Marc Sala-Faig, Aitziber Zufiaurre, Sergi Pla-Rabes, Marisol Felip, Jordi Catalan
Summary: Experimental nutrient additions are important for studying plankton ecology. A new enclosure type is described that minimizes manipulation of planktonic communities. This enclosure design is inexpensive, easy to build, and can be used in lakes that are difficult to reach.
JOURNAL OF PLANKTON RESEARCH
(2023)
Article
Biochemistry & Molecular Biology
Mateu Menendez-Serra, Vicente J. Ontiveros, Joan Caliz, David Alonso, Emilio O. Casamayor
Summary: This study examines the assembly processes of bacterial and microeukaryotic communities along a salinity gradient and reveals that increasing salinity leads to a dominant role of selection over dispersal, resulting in decreased community turnover. The richness of microeukaryotes decreases with increasing salinity, suggesting that the net effect of selection and dispersal is determined by environmental conditions and microbial ecologies.
Article
Plant Sciences
Carles Castano, Sara Hallin, Dagmar Egelkraut, Bjorn D. Lindahl, Johan Olofsson, Karina Engelbrecht Clemmensen
Summary: Global vegetation regimes have different dynamics in belowground carbon (C) and nitrogen (N), but it is challenging to separate large-scale climatic controls from intrinsic plant-soil-microbial feedback effects. In local gradients with similar pedo-climatic conditions, the effects of plant-microbial feedbacks can be isolated from large-scale drivers. In a subarctic-alpine mosaic, contrasting plant-microbial feedbacks contribute to diverging soil C : N ratios at the landscape scale.
Review
Biochemical Research Methods
Emilio O. Casamayor, Joan Caliz, Xavier Triado-Margarit, Stephen B. Pointing
Summary: The atmosphere plays a significant role in the intercontinental dispersal of harmful microorganisms, antibiotic resistance genes, and allergens, with implications for ecosystem functioning and global health. Long-distance dispersal is influenced by air movement at higher altitudes and is affected by human activities, climate change, and atmospheric circulation. However, there is limited data on the survival of microorganisms during atmospheric transport and their invasive potential. This paper highlights the importance of understanding intercontinental microbial dispersal and offers a roadmap for further research in this area.
CURRENT OPINION IN BIOTECHNOLOGY
(2023)
Article
Ecology
Eerika Albrecht, Olga Hannonen, Carlos Palacin-Lizarbe, Jarno Suni, Laura H. Haerkonen, Niko Soininen, Jussi Kukkonen, Anssi Vainikka
Summary: In this paper, the process of browning in boreal lakes surrounded by managed forests and wetlands is reviewed, and the ecological consequences and ecosystem-based management of browning are discussed. Survey data on public perceptions of water quality in Finland are presented to understand the impact of browning on recreational fishing tourism. The need to go beyond the EU's Water Framework Directive and improve understanding of microbial processes within lakes is highlighted.
ECOLOGICAL APPLICATIONS
(2023)
Article
Biodiversity Conservation
Anna Edlinger, Gina Garland, Samiran Banerjee, Florine Degrune, Pablo Garcia-Palacios, Chantal Herzog, David Sanchez Pescador, Sana Romdhane, Masahiro Ryo, Aurelien Saghai, Sara Hallin, Fernando T. T. Maestre, Laurent Philippot, Matthias C. C. Rillig, Marcel G. A. van Der Heijden
Summary: Organic carbon and aggregate stability are important aspects of soil quality when considering soil’s potential as a carbon sink in agriculture. This study evaluated the impact of various factors, including climatic conditions, soil properties, and agricultural practices, on soil organic carbon and aggregate stability across a large geographical gradient in Europe. The findings highlighted the significant role of land use, aridity, and calcium content in determining soil aggregation and organic carbon storage.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Soil Science
Ingrid Rijk, Linn Berkelund, Alf Ekblad, Sara Hallin, Dan B. Kleja, Astrid Taylor, Maria Viketoft, Christopher Jones
Summary: Heavy metal pollution has significant effects on ecosystem nitrogen cycling. This study investigated the effects of copper on microbial guilds and plant responses in two different grassland soils. The results showed that higher copper treatments resulted in lower microbial abundances, potential ammonia oxidation rates, and plant biomass. Additionally, plants had increased nitrogen content and enriched shoot nitrogen isotope with higher copper concentrations.
SOIL BIOLOGY & BIOCHEMISTRY
(2023)
Article
Microbiology
Yvonne Bosch, Grace Pold, Aurelien Saghai, Magnus Karlsson, Christopher M. Jones, Sara Hallin
Summary: Fungal denitrifiers are sparse but cosmopolitan in soils, dominated by saprotrophs and pathogens. Bacterial and archaeal denitrifiers, rather than fungal denitrifiers, are the main contributors to N2O emissions.
MICROBIOLOGY SPECTRUM
(2023)
Article
Environmental Sciences
Monique E. Smith, Giulia Vico, Alessio Costa, Timothy Bowles, Amelie C. M. Gaudin, Sara Hallin, Christine A. Watson, Remedios Alarcon, Antonio Berti, Andrzej Blecharczyk, Francisco J. Calderon, Steve Culman, William Deen, Craig F. Drury, Axel Garcia Y. Garcia, Andres Garcia-Diaz, Eva Hernandez Plaza, Krzysztof Jonczyk, Ortrud Jack, R. Michael Lehman, Francesco Montemurro, Francesco Morari, Andrea Onofri, Shannon L. Osborne, Jose Luis Tenorio Pasamon, Boel Sandstrom, Ines Santin-Montanya, Zuzanna Sawinska, Marty R. Schmer, Jaroslaw Stalenga, Jeffrey Strock, Francesco Tei, Cairistiona F. E. Topp, Domenico Ventrella, Robin L. Walker, Riccardo Bommarco
Summary: Grain yield data from 32 long-term experiments across Europe and North America suggest that increasing crop functional richness in rotations can support grain yields more than species diversity. Diversifying agriculture through crop rotation and increasing crop species diversity can reduce negative impacts on the environment and maintain yields. However, it is unclear how cereal yields change with crop rotation diversity and external nitrogen fertilization level over time, and which functional groups of crops provide the most yield benefit.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)
Article
Biology
Vicente J. Ontiveros, Jose A. Capitan, Emilio O. Casamayor, David Alonso
Summary: Fitness equalizing mechanisms, such as trade-offs, play an important role in promoting species coexistence in bacterial communities. Through studying diverse bacterial communities in different systems, it was found that these mechanisms exist and are driven by different subsets of species. Rare taxa are the drivers in aquatic communities, while the core sub-community is the driver in soils. This study suggests that the importance of fitness equalization mechanisms in bacterial communities may have been underestimated.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2023)
Article
Plant Sciences
Dora Straus, Miguel Angel Redondo, Carles Castano, Jaanis Juhanson, Karina E. Clemmensen, Sara Hallin, Jonas Oliva
Summary: This study examines the influence of root-associated microbiota on the growth of boreal tree species. The observed plant-soil feedbacks mirror the successional patterns found in boreal forests, suggesting a possible contribution of soil microbiota to the successional progression. Species-specific ectomycorrhizal fungi and a few bacteria rather than fungal plant pathogens or oomycetes seem to drive the feedbacks by promoting seedling growth in heterospecific soils.
JOURNAL OF ECOLOGY
(2023)
