Nitrogen fixation and diazotroph diversity in groundwater systems

The ISME Journal, Journal Year: 2023, Volume and Issue: 17(11), P. 2023 - 2034

Published: Sept. 15, 2023

Abstract Biological nitrogen fixation (BNF), the conversion of N2 into bioavailable (N), is main process for replenishing N loss in biosphere. However, BNF groundwater systems remains poorly understood. In this study, we examined activity, abundance, and community composition diazotrophs Hetao Plain Inner Mongolia using 15N tracing methods, reverse transcription qPCR (RT-qPCR), metagenomic/metatranscriptomic analyses. 15N2 incubation near situ (9.5–585.4 nmol L−1 h−1) N2-fixer enrichment isolates (13.2–1728.4 g−1 h−1, as directly verified by single-cell resonance Raman spectroscopy), suggested that a non-negligible source region. The expression nifH genes ranged from 3.4 × 103 to 1.2 106 copies was tightly correlated with dissolved oxygen (DO), Fe(II), NH4+. Diazotrophs were chiefly aerobes or facultative anaerobes, dominated Stutzerimonas, Pseudomonas, Paraburkholderia, Klebsiella, Rhodopseudomonas, Azoarcus, additional uncultured populations. Active diazotrophs, which prefer reducing conditions, more metabolically diverse potentially associated nitrification, sulfur/arsenic mobilization, Fe(II) transport, CH4 oxidation. Our results highlight importance subsurface geochemical cycles.

Language: Английский

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Nitrogen Cycling Across a Salinity Gradient From the Pearl River Estuary to Offshore: Insight From Nitrate Dual Isotopes

Journal of Geophysical Research Biogeosciences, Journal Year: 2022, Volume and Issue: 127(5)

Published: April 20, 2022

Abstract Dual isotope measurements were performed on nitrate (δ 15 N‐NO 3 − and δ 18 O‐NO ) in the Pearl River Estuary (PRE) adjacent northern South China Sea (NSCS) to investigate sources its biogeochemical processes during rainy season. Our results indicated that PRE, high levels associated with intense human activities PRE delta, of which included reduced nitrogen (N) fertilizer (29%), SN (nitrate derived from soil N) (18%), manure sewage (10%), atmospheric deposition (7%). In nearshore area, was characterized by relatively values suggestive incomplete assimilation. Besides, nitrification might be significant intermediate bottom waters due ammonia release remineralization sinking sedimented organic matter (OM). offshore depleted nearly complete utilization, showed moderate values. addition, exhibited a clear vertical gradient decrease surface bottom. A coupled nitrification‐denitrification process sediment porewater supposed, left imprints area. although assimilation prominent process, relationship deviated 1:1 line, suggesting contribution increased offshore. study suggests external source shifts anthropogenic continuous river–estuary–ocean system, become more active as it goes seaward.

Language: Английский

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Diel change in inorganic nitrogenous nutrient dynamics and associated oxygen stoichiometry along the Pearl River Estuary

Water Research, Journal Year: 2022, Volume and Issue: 222, P. 118954 - 118954

Published: Aug. 1, 2022

Language: Английский

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Impact of seasonal change on dissimilatory nitrate reduction to ammonium (DNRA) triggering the retention of nitrogen in lake

Journal of Environmental Management, Journal Year: 2023, Volume and Issue: 341, P. 118050 - 118050

Published: May 2, 2023

Language: Английский

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Adaptation of Archaeal Communities to Summer Hypoxia in the Sediment of Bohai Sea

Ecology and Evolution, Journal Year: 2025, Volume and Issue: 15(1)

Published: Jan. 1, 2025

ABSTRACT Understanding the adaptation of archaea to hypoxia is essential for deciphering functions and mechanisms microbes when suffering environmental changes. However, dynamics responses sedimentary in Bohai Sea are still unclear. In this study, diversity, composition, distribution archaeal community sediment along an inshore–offshore transect across oxygen‐depleted area were investigated June, July, August 2021 by employing high‐throughput sequencing 16S rRNA gene. Results indicated that communities dominated Thermoproteota (80.61%), Asgardarchaeota (8.70%), Thermoplasmatota (5.27%). Dissolved oxygen (DO) NO 3 − two key factors shaping communities, accounting 49.5% 38.3% total variabilities ( p < 0.05), respectively. With intensity depletion, diversity increased significantly. Microbial networks revealed Bathyarchaeia played a role interacting with both bacteria other groups. Furthermore, adaptions also displayed variation relative abundance predicted ecological metabolic pathways. The enrichment specific nitrogen transformation enzymes showed potential fixation removal, which might contribute balance N budget thus facilitate restoration under eutrophication Sea. Our results provided new picture on archaea, will be beneficial further investigations extreme environments theoretically practically.

Language: Английский

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Hotspots and future trends of estuarine nitrogen cycle: A bibliometric review

Journal of Hydrology, Journal Year: 2025, Volume and Issue: unknown, P. 133056 - 133056

Published: March 1, 2025

Language: Английский

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Sedimentary recorded nitrogen-transforming microbes reflect climate fluctuations in a glacial lake on the Qinghai-Tibetan Plateau over a millennium timescale

Journal of Great Lakes Research, Journal Year: 2025, Volume and Issue: unknown, P. 102579 - 102579

Published: April 1, 2025

Language: Английский

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The distribution of functional nitrogen cycle gene in river and their response to nitrogen concentrations

Journal of environmental chemical engineering, Journal Year: 2025, Volume and Issue: unknown, P. 116637 - 116637

Published: April 1, 2025

Language: Английский

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Metal concentration in freshwater sediments is linked to microbial biodiversity and community composition

Environment International, Journal Year: 2025, Volume and Issue: unknown, P. 109465 - 109465

Published: April 1, 2025

The effect of metals on freshwater microbiomes is poorly understood compared to other factors, such as nutrients or climate. While deleterious effects plant and animal biodiversity are well documented, the role in shaping biodiversity, composition functional potential sediment microbial communities remains unknown. Therefore, we explored if metal concentrations can be linked alterations communities. We collected sediments from 34 streams lakes Switzerland grouped them based their content. Microbial diversity community were determined using 16S rRNA gene amplicon sequencing. Most not contaminated with according Sediment Environmental Quality Criteria, although some stations exceeded limits for Cu, Zn, Pb. Nevertheless, correlational analysis indicated links various aspects biodiversity. Al significantly (p < 0.05) correlated richness. further observed a predominantly negative correlation between abundances dominant taxa. Predicted that different types have potential. For example, Mn exhibited significant positive nitrogen fixation potential, whereas Pb, Zn displayed correlation. Overall, our findings indicate may alter even at ambient concentrations. Further research into drivers factors loss warranted.

Language: Английский

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Remote estimates of total suspended matter in China’s main estuaries using Landsat images and a weight random forest model

ISPRS Journal of Photogrammetry and Remote Sensing, Journal Year: 2021, Volume and Issue: 183, P. 94 - 110

Published: Nov. 13, 2021

Language: Английский

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