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Dai M, Xu Y, Genjebay Y, Lu L, Wang C, Yang H, Huang C, Huang T. Urbanization significantly increases greenhouse gas emissions from a subtropical headwater stream in Southeast China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:173508. [PMID: 38851353 DOI: 10.1016/j.scitotenv.2024.173508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 05/09/2024] [Accepted: 05/23/2024] [Indexed: 06/10/2024]
Abstract
Streams are disproportionately significant contributors to increases in greenhouse gas (GHG) effluxes in river networks. In the context of global urbanization, a growing number of streams are affected by urbanization, which has been suggested to stimulate the water-air GHG emissions from fluvial systems. This study investigated the seasonal and longitudinal profiles of GHG (N2O, CH4, and CO2) concentrations of Jiuxianghe Stream, a headwater stream undergoing urbanization, and estimated its GHG diffusive fluxes and global warming potentials (GWPs) using the boundary layer method. The results showed that N2O, CH4, and CO2 concentrations in Jiuxianghe Stream were 0.45-7.19 μg L-1, 0.31-586.85 μg L-1, and 0.16-11.60 mg L-1, respectively. N2O, CH4, and CO2 concentrations in the stream showed 4.55-, 23.70-, and 7.68-fold increases from headwaters to downstream, respectively, corresponding to the forest-urban transition within the watershed. Multiple linear regression indicated that NO3--N, NH4+-N, and DOC:NO3--N accurately predicted N2O and CO2 concentrations, indicating that N nutrients were the driving factors. The Jiuxianghe Stream was a source of atmospheric GHGs with a daily GWP of 7.31 g CO2-eq m-2 d-1 on average and was significantly positively correlated with the ratio of construction land and forest in the sub-watershed. This study highlights the critical role of urbanization in amplifying GHG emissions from streams, thereby augmenting our understanding of GHG emissions from river networks. With global urbanization on the rise, streams experiencing urbanization are expected to make an unprecedentedly significant contribution to riverine GHG budgets in the future.
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Affiliation(s)
- Mutan Dai
- School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023, China
| | - Yuanhui Xu
- School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023, China
| | | | - Lingfeng Lu
- School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023, China
| | - Chuan Wang
- School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023, China
| | - Hao Yang
- School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023, China
| | - Changchun Huang
- School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023, China
| | - Tao Huang
- School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023, China.
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Cao M, Wang F, Ma S, Geng H, Sun K. Recent advances on greenhouse gas emissions from wetlands: Mechanism, global warming potential, and environmental drivers. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 355:124204. [PMID: 38788989 DOI: 10.1016/j.envpol.2024.124204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 05/06/2024] [Accepted: 05/21/2024] [Indexed: 05/26/2024]
Abstract
Greenhouse gas (GHG) emissions from wetlands have exacerbated global warming, attracting worldwide attention. However, the research process and development trends in this field remain unknown. Herein, 1865 papers related to wetlands GHG emissions published from January 2000 to December 2023 were selected, and CiteSpace and VOSviewer were used for bibliometric analysis to visually analyze the publications distribution, research authors, organizations and countries, core journal and keywords, and discussed the research progress, trends and hotspots in the fields. Over the past 24 years, the research has gone through three phases: the "embryonic" stage (2000-2006), the accumulation stage (2007-2014), and the acceleration stage (2015-2023). China has played a pivotal role in this domain, publishing the most papers and working closely with the United States, United Kingdom, Canada, Germany, and Australia. In addition, this study synthesized 311 field observations from 123 publications to analyze the variability in GHG emissions and their driving factors in four different types of natural wetlands. The results suggested that the average carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes in different wetlands were significantly different. River wetlands exhibited the highest GHG fluxes, while marsh wetlands demonstrated greater global warming potential (GWP). The average CO2, CH4 and N2O fluxes were 60.41 mg m-2·h-1, 2.52 mg m-2·h-1 and 0.05 mg m-2·h-1, respectively. The GWP of Chinese natural wetlands was estimated as 648.72 Tg·CO2-eq·yr-1, and CH4 contributed the largest warming effect, accounting for 57.43%. Correlation analysis showed that geographical location, climate factors, and soil conditions collectively regulated GHG emissions from wetlands. The findings provide a new perspective on sustainable wetland management and reducing GHG emissions.
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Affiliation(s)
- Manman Cao
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875, Beijing, China
| | - Fei Wang
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875, Beijing, China.
| | - Shuai Ma
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875, Beijing, China
| | - Huanhuan Geng
- School of Energy & Environmental Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, 100083, Beijing, China
| | - Ke Sun
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875, Beijing, China
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3
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Qu Q, Hu X, Feng R. Using the Potential Transformation of Dissolved Organic Matter to Understand Carbon Emissions from Inland Rivers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 39078620 DOI: 10.1021/acs.est.4c00506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/31/2024]
Abstract
Understanding the transformation of river dissolved organic matter (DOM) is important for assessing the emissions of greenhouse gases (GHGs) in inland waters. However, the relationships between the variations in DOM components and GHGs remain largely unknown. Here, parallel factor analysis (PARAFAC) was applied to investigate the DOM components in 46 inland rivers in China. We found that the GHG emissions in peri-urban rivers were 1.10-2.15 times greater than those in urban rivers. Microbial and environmental factors (e.g., living cell numbers, microbial activity and pH) explained more than 70% of the total variance in GHG emissions in rivers. DOM variations relationships between different components ware revealed based on compositional data principal component analysis (CoDA-PCA). Microbial-mediated DOM production and degradation were quantified, and the degradation levels in peri-urban rivers were 11.8-25.2% greater than those in urban rivers. Differences in carbon emission potential between urban and peri-urban rivers were related to DOM variances and transformations and were affected by water chemistry (e.g., NH4-N and As). This study clarifies the regulatory effects of DOM composition variations and transformations on GHG emissions, and enhances the understanding of the DOM biogeochemical cycle.
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Affiliation(s)
- Qian Qu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Carbon Neutrality Interdisciplinary Science Centre, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Xiangang Hu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Carbon Neutrality Interdisciplinary Science Centre, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Ruihong Feng
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Carbon Neutrality Interdisciplinary Science Centre, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
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Yang F, Zheng X, Wang D, Yao E, Li Y, Huang W, Zhang L, Wang J, Zhong J. Significant diurnal variations in nitrous oxide (N 2O) emissions from two contrasting habitats in a large eutrophic lake (Lake Taihu, China). ENVIRONMENTAL RESEARCH 2024; 261:119691. [PMID: 39074775 DOI: 10.1016/j.envres.2024.119691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 06/27/2024] [Accepted: 07/25/2024] [Indexed: 07/31/2024]
Abstract
Algae and macrophytes in lake ecosystems regulate nitrous oxide (N2O) emissions from eutrophic lakes. However, knowledge of diurnal N2O emission patterns from different habitats remains limited. To understand the diurnal patterns and driving mechanisms of N2O emissions from contrasting habitats, continuous in situ observations (72 h) of N2O fluxes from an algae-dominated zone (ADZ) and reed-dominated zone (RDZ) in Lake Taihu were conducted using the Floating Chamber method. The results showed average N2O emission fluxes of 0.15 ± 0.06 and 0.02 ± 0.04 μmol m-2 h-1 in the ADZ and RDZ in autumn, respectively. The significantly higher (p < 0.05) N2O fluxes in the ADZ were mainly attributed to differences in nitrogen (N) levels. The results also showed significant diurnal differences (p < 0.05) in the N2O emission fluxes within the ADZ and RDZ, and daytime fluxes were significantly higher (p < 0.05) than nighttime fluxes. The statistical results indicated that N2O emissions from the ADZ were mainly driven by diurnal variations in N loading and the dissolved oxygen (DO) concentration, and those from the RDZ were more influenced by DO, redox potential, and pH. Finally, we determined the proper time for routine monitoring of N2O flux in the two habitats. Our results highlight the importance of considering diverse habitats and diurnal variations when estimating N2O budgets at a whole-lake scale.
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Affiliation(s)
- Fanyan Yang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, PR China; School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, PR China
| | - Xiaolan Zheng
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, PR China
| | - Dongqi Wang
- School of Geographical Sciences, Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, PR China
| | - Enqin Yao
- Huzhou Ecological and Environmental Monitoring Center, Zhejiang Province, Huzhou, 313000, PR China
| | - Yunchuang Li
- China Construction First Group Corporation Limited, Beijing, 100161, PR China
| | - Wei Huang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, PR China
| | - Lei Zhang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, PR China
| | - Jianjun Wang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, PR China
| | - Jicheng Zhong
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, PR China.
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Song K, Wang S, Xu X, Ma J, Yang Y, Zeng Y, Li J, Zhou X, Zhou Y. Benthic clade II-type nitrous oxide reducers suppress nitrous oxide emissions in shallow lakes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 931:172908. [PMID: 38697552 DOI: 10.1016/j.scitotenv.2024.172908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/07/2024] [Accepted: 04/29/2024] [Indexed: 05/05/2024]
Abstract
Shallow lakes, recognized as hotspots for nitrogen cycling, contribute to the emission of the potent greenhouse gas nitrous oxide (N2O), but the current emission estimates for this gas have a high degree of uncertainty. However, the role of N2O-reducing bacteria (N2ORB) as N2O sinks and their contribution to N2O reduction in aquatic ecosystems in response to N2O dynamics have not been determined. Here, we investigated the N2O dynamics and microbial processes in the nitrogen cycle, which included both N2O production and consumption, in five shallow lakes spanning approximately 500 km. The investigated sites exhibited N2O oversaturation, with excess dissolved N2O concentrations (ΔN2O) ranging from 0.55 ± 0.61 to 53.17 ± 15.75 nM. Sediment-bound N2O (sN2O) was significantly positively correlated with the nitrate concentration in the overlying water (p < 0.05), suggesting that nitrate accumulation contributes to benthic N2O generation. High N2O consumption activity (RN2O) corresponded to low ΔN2O. In addition, a significant negative correlation was found between RN2O and nir/nosZ, showing that bacteria encoding nosZ contributed to N2O consumption in the benthic sediments. Redundancy analysis indicated that benthic functional genes effectively reflected the variations in RN2O and ∆N2O. qPCR analysis revealed that the clade II nosZ gene was more sensitive to ΔN2O than the clade I nosZ gene. Furthermore, four novel genera of potential nondenitrifying N2ORB were identified based on metagenome-assembled genome analysis. These genera, which are affiliated with clade II, lack genes responsible for N2O production. Collectively, benthic N2ORB, especially for clade II-type N2ORB, harnesses N2O consumption activity leading to low N2O emissions from shallow lakes. This study advances our knowledge of the role of benthic clade II-type N2ORB in regulating N2O emissions in shallow lakes.
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Affiliation(s)
- Kang Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Siyu Wang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China; School of Environmental Studies, China University of Geosciences, Wuhan 430074, China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Xiaoguang Xu
- School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Jie Ma
- Ministry of Ecology and Environment, Nanjing Institute of Environment Sciences, Nanjing 210042, China
| | - Yuxuan Yang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China; School of Environment, Nanjing Normal University, Nanjing 210023, China
| | - Yuli Zeng
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Jining Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Xiaohong Zhou
- School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Yiwen Zhou
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China.
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Wang S, Li S, Ji M, Li J, Huang J, Dang Z, Jiang Z, Zhang S, Zhu X, Ji G. Long-neglected contribution of nitrification to N 2O emissions in the Yellow River. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 351:124099. [PMID: 38703980 DOI: 10.1016/j.envpol.2024.124099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 04/28/2024] [Accepted: 05/01/2024] [Indexed: 05/06/2024]
Abstract
Rivers play a significant role in the global nitrous oxide (N2O) budget. However, the microbial sources and sinks of N2O in river systems are not well understood or quantified, resulting in the prolonged neglect of nitrification. This study investigated the isotopic signatures of N2O, thereby quantifying the microbial source of N2O production and the degree of N2O reduction in the Yellow River. Although denitrification has long been considered to be the dominant pathway of N2O production in rivers, our findings indicated that denitrification only accounted for 18.3% (8.2%-43.0%) of the total contribution to N2O production in the Yellow River, with 50.2%-80.2% being concurrently reduced. The denitrification contribution to N2O production (R2 = 0.44, p < 0.01) and N2O reduction degree (R2 = 0.70, p < 0.01) were positively related to the dissolved organic carbon (DOC) content. Similar to urban rivers and eutrophic lakes, denitrification was the primary process responsible for N2O production (43.0%) in certain reaches with high organic content (DOC = 5.29 mg/L). Nevertheless, the denitrification activity was generally constrained by the availability of electron donors (average DOC = 2.51 mg/L) throughout the Yellow River basin. Consequently, nitrification emerged as the primary contributor in the well-oxygenated Yellow River. Additionally, our findings further distinguished the respective contribution of ammonia-oxidizing bacteria (AOB) and archaea (AOA) to N2O emissions. Although AOB dominated the N2O production in the Yellow River, the AOA specie abundance (AOA/(AOA + AOB)) contributed up to 32.6%, which resulted in 25.6% of the total nitrifier-produced N2O, suggesting a significant occurrence of AOA in the oligotrophic Yellow River. Overall, this study provided a non-invasive approach for quantifying the microbial sources and sinks to N2O emissions, and demonstrated the substantial role of nitrification in the large oligotrophic rivers.
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Affiliation(s)
- Shuo Wang
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China
| | - Shengjie Li
- Department of Biogeochemistry, Max Planck Institute for Marine Microbiology, 28359, Bremen, Germany
| | - Mingfei Ji
- Collaborative Innovation Centre of Water Security for the Water Source Region of the Mid-line of the South-to-North Diversion Project of Henan Province, College of Life Sciences and Agricultural Engineering, Nanyang Normal University, Nanyang, 473061, China
| | - Jiarui Li
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China
| | - Jilin Huang
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China
| | - Zhengzhu Dang
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China
| | - Zhuo Jiang
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China
| | - Shuqi Zhang
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China
| | - Xianfang Zhu
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China
| | - Guodong Ji
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing, 100871, China.
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Sun C, Liu N, Song J, Chen L, Zhang Y, Wang X. High-Resolution Estimates of N 2O Emissions from Inland Waters and Wetlands in China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:8736-8747. [PMID: 38723264 DOI: 10.1021/acs.est.4c02229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Inland waters (rivers, lakes, and reservoirs) and wetlands (marshes and coastal wetlands) represent large and continuous sources of nitrous oxide (N2O) emissions, in view of adequate biomass and anaerobic conditions. Considerable uncertainties remain in quantifying spatially explicit N2O emissions from aquatic systems, attributable to the limitations of models and a lack of comprehensive data sets. Herein, we conducted a synthesis of 1659 observations of N2O emission rates to determine the major environmental drivers across five aquatic systems. A framework for spatially explicit estimates of N2O emissions in China was established, employing a data-driven approach that upscaled from site-specific N2O fluxes to robust multiple-regression models. Results revealed the effectiveness of models incorporating soil organic carbon and water content for marshes and coastal wetlands, as well as water nitrate concentration and dissolved organic carbon for lakes, rivers, and reservoirs for predicting emissions. Total national N2O emissions from inland waters and wetlands were 1.02 × 105 t N2O yr-1, with contributions from marshes (36.33%), rivers (27.77%), lakes (25.27%), reservoirs (6.47%), and coastal wetlands (4.16%). Spatially, larger emissions occurred in the Songliao River Basin and Continental River Basin, primarily due to their substantial terrestrial biomass. This study offers a vital national inventory of N2O emissions from inland waters and wetlands in China, providing paradigms for the inventorying work in other countries and insights to formulate effective mitigation strategies for climate change.
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Affiliation(s)
- Cheng Sun
- Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, Jilin 130021, China
- Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun ,Jilin 130021, China
- College of New Energy and Environment, Jilin University, Changchun, Jilin 130021, China
| | - Nuo Liu
- Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, Jilin 130021, China
- Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun ,Jilin 130021, China
- College of New Energy and Environment, Jilin University, Changchun, Jilin 130021, China
| | - Junnian Song
- Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, Jilin 130021, China
- Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun ,Jilin 130021, China
- College of New Energy and Environment, Jilin University, Changchun, Jilin 130021, China
- The Bartlett School of Sustainable Construction, University College London, London WC1E 7HB, U.K
| | - Lei Chen
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Ying Zhang
- Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, Jilin 130021, China
- Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun ,Jilin 130021, China
- College of New Energy and Environment, Jilin University, Changchun, Jilin 130021, China
| | - Xian'en Wang
- Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, Jilin 130021, China
- Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun ,Jilin 130021, China
- College of New Energy and Environment, Jilin University, Changchun, Jilin 130021, China
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8
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Deng M, Yeerken S, Wang Y, Li L, Li Z, Oon YS, Oon YL, Xue Y, He X, Zhao X, Song K. Greenhouse gases emissions from aquaculture ponds: Different emission patterns and key microbial processes affected by increased nitrogen loading. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:172108. [PMID: 38556013 DOI: 10.1016/j.scitotenv.2024.172108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/28/2024] [Accepted: 03/28/2024] [Indexed: 04/02/2024]
Abstract
Global aquaculture production is expected to rise to meet the growing demand for food worldwide, potentially leading to increased anthropogenic greenhouse gases (GHG) emissions. As the demand for fish protein increases, so will stocking density, feeding amounts, and nitrogen loading in aquaculture ponds. However, the impact of GHG emissions and the underlying microbial processes remain poorly understood. This study investigated the GHG emission characteristics, key microbial processes, and environmental drivers underlying GHG emissions in low and high nitrogen loading aquaculture ponds (LNP and HNP). The N2O flux in HNP (43.1 ± 11.3 μmol m-2 d-1) was significantly higher than in LNP (-11.3 ± 25.1 μmol m-2 d-1), while the dissolved N2O concentration in HNP (52.8 ± 7.1 nmol L-1) was 150 % higher than in LNP (p < 0.01). However, the methane (CH4) and carbon dioxide (CO2) fluxes and concentrations showed no significant differences (p > 0.05). N2O replaced CH4 as the main source of Global Warming Potential in HNP. Pond sediments acted as a sink for N2O but a source for CH4 and CO2. The △N2O/(△N2O + △N2) in HNP (0.015 ± 0.007 %) was 7.7-fold higher than in LNP (0.002 ± 0.001 %) (p < 0.05). The chemical oxygen demand to NO2-N ratio was the most important environmental factor explaining the variability of N2O fluxes. Ammonia-oxidizing bacteria driven nitrification in water was the predominant N2O source, while comammox-driven nitrification and nosZII-driven N2O reduction in water were key processes for reducing N2O emission in LNP but decreased in HNP. The strong CH4 oxidization by Methylocystis and CO2 assimilation by algae resulted in low CH4 emissions and CO2 sink in the aquaculture pond. The Mantel test indicated that HNP increased N2O fluxes mainly through altering functional genes composition in water and sediment. Our findings suggest that there is a significant underestimation of N2O emissions without considering the significantly increased △N2O/(△N2O + △N2) caused by increased nitrogen loading.
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Affiliation(s)
- Min Deng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Senbati Yeerken
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuren Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lu Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Zhouyang Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yoong-Sin Oon
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yoong-Ling Oon
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yunpeng Xue
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xugang He
- College of Fisheries, Huazhong Agricultural University, Wuhan 430072, China
| | - Xiaoli Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Kang Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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9
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Jia Y, Hu X, Kang W, Dong X. Unveiling Microbial Nitrogen Metabolism in Rivers using a Machine Learning Approach. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6605-6615. [PMID: 38566483 DOI: 10.1021/acs.est.3c09653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Microbial nitrogen metabolism is a complicated and key process in mediating environmental pollution and greenhouse gas emissions in rivers. However, the interactive drivers of microbial nitrogen metabolism in rivers have not been identified. Here, we analyze the microbial nitrogen metabolism patterns in 105 rivers in China driven by 26 environmental and socioeconomic factors using an interpretable causal machine learning (ICML) framework. ICML better recognizes the complex relationships between factors and microbial nitrogen metabolism than traditional linear regression models. Furthermore, tipping points and concentration windows were proposed to precisely regulate microbial nitrogen metabolism. For example, concentrations of dissolved organic carbon (DOC) below tipping points of 6.2 and 4.2 mg/L easily reduce bacterial denitrification and nitrification, respectively. The concentration windows for NO3--N (15.9-18.0 mg/L) and DOC (9.1-10.8 mg/L) enabled the highest abundance of denitrifying bacteria on a national scale. The integration of ICML models and field data clarifies the important drivers of microbial nitrogen metabolism, supporting the precise regulation of nitrogen pollution and river ecological management.
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Affiliation(s)
- Yuying Jia
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Xiangang Hu
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Weilu Kang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Xu Dong
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
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10
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Li J, Liang E, Deng C, Li B, Cai H, Ma R, Xu Q, Liu J, Wang T. Labile dissolved organic matter (DOM) and nitrogen inputs modified greenhouse gas dynamics: A source-to-estuary study of the Yangtze River. WATER RESEARCH 2024; 253:121318. [PMID: 38387270 DOI: 10.1016/j.watres.2024.121318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Revised: 02/07/2024] [Accepted: 02/14/2024] [Indexed: 02/24/2024]
Abstract
Although rivers are increasingly recognized as essential sources of greenhouse gases (GHG) to the atmosphere, few systematic efforts have been made to reveal the drivers of spatiotemporal variations of dissolved GHG (dGHG) in large rivers under increasing anthropogenic stress and intensified hydrological cycling. Here, through a source-to-estuary survey of the Yangtze River in March (spring) and October (autumn) of 2018, we revealed that labile dissolved organic matter (DOM) and nitrogen inputs remarkably modified the spatiotemporal distribution of dGHG. The average partial pressure of CO2 (pCO2), CH4 and N2O concentrations of all sampling sites in the Yangtze River were 1015 ± 225 μatm, and 87.5± 36.5 nmol L-1, and 20.3 ± 6.6 nmol L-1, respectively, significantly lower than the global average. In terms of longitudinal and seasonal variations, higher GHG concentrations were observed in the middle-lower reach in spring. The dominant drivers of spatiotemporal variations in dGHG were labile, protein-like DOM components and nitrogen level. Compared with the historical data of dGHG from published literature, we found a significant increase in N2O concentrations in the Yangtze River during 2004-2018, and the increasing trend was consistent with the rising riverine nitrogen concentrations. Our study emphasized the critical roles of labile DOM and nitrogen inputs in driving the spatial hotspots, seasonal variations and annual trends of dGHG. These findings can contribute to constraining the global GHG budget estimations and controls of GHG emission in large rivers in response to global change.
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Affiliation(s)
- Jiarui Li
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Enhang Liang
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Chunfang Deng
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Bin Li
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Hetong Cai
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China
| | - Ruoqi Ma
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China; General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Resources, Beijing 100120, PR China
| | - Qiang Xu
- School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin 15030, PR China
| | - Jiaju Liu
- Research Center for Integrated Control of Watershed Water Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China.
| | - Ting Wang
- College of Environmental Sciences and Engineering, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Peking University, Beijing 100871, PR China; State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems, Beijing 100871, PR China.
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11
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Xie R, Lin L, Shi C, Zhang P, Rao P, Li J, Izabel-Shen D. Elucidating the links between N 2O dynamics and changes in microbial communities following saltwater intrusions. ENVIRONMENTAL RESEARCH 2024; 245:118021. [PMID: 38147917 DOI: 10.1016/j.envres.2023.118021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/18/2023] [Accepted: 12/22/2023] [Indexed: 12/28/2023]
Abstract
Saltwater intrusion in estuarine ecosystems alters microbial communities as well as biogeochemical cycling processes and has become a worldwide problem. However, the impact of salinity intrusion on the dynamics of nitrous oxide (N2O) and associated microbial community are understudied. Here, we conducted field microcosms in a tidal estuary during different months (December, April and August) using dialysis bags, and microbes inside the bags encountered a change in salinity in natural setting. We then compared N2O dynamics in the microcosms with that in natural water. Regardless of incubation environment, saltwater intrusion altered the dissolved N2O depending on the initial saturation rates of N2O. While the impact of saltwater intrusion on N2O dynamics was consistent across months, the dissolved N2O was higher in summer than in winter. The N-related microbial communities following saltwater intrusion were dominated by denitrifers, with fewer nitrifiers and bacterial taxa involved in dissimilatory nitrate reduction to ammonium. While denitrification was a significant driver of N2O dynamics in the studied estuary, nitrifier-involved denitrification contributed to the additional production of N2O, evidenced by the strong associations with amoA genes and the abundance of Nitrospira. Higher N2O concentrations in the field microcosms than in natural water limited N2O consumption in the former, given the lack of an association with nosZ gene abundance. The differences in the N2O dynamics observed between the microcosms and natural water could be that the latter comprised not only indigenous microbes but also those accompanied with saltwater intrusion, and that immigrants might be functionally rich individuals and able to perform N transformation in multiple pathways. Our work provides the first quantitative assessment of in situ N2O concentrations in an estuary subjected to a saltwater intrusion. The results highlight the importance of ecosystem size and microbial connectivity in the source-sink dynamics of N2O in changing environments.
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Affiliation(s)
- Rongrong Xie
- College of Environmental and Resource Science, Fujian Normal University, Fuzhou, 350117, China; Key Laboratory of Pollution Control and Resource Recycling of Fujian Province, Fujian Normal University, Fuzhou, 350117, China; Leibniz Institute for Baltic Sea Research, Warnemünde, Rostock, 18119, Germany.
| | - Laichang Lin
- College of Environmental and Resource Science, Fujian Normal University, Fuzhou, 350117, China
| | - Chengchun Shi
- Fujian Research Academy of Environmental Sciences, Fuzhou, 350013, China
| | - Peng Zhang
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China
| | - Peiyuan Rao
- College of Environmental and Resource Science, Fujian Normal University, Fuzhou, 350117, China
| | - Jiabing Li
- College of Environmental and Resource Science, Fujian Normal University, Fuzhou, 350117, China; Key Laboratory of Pollution Control and Resource Recycling of Fujian Province, Fujian Normal University, Fuzhou, 350117, China
| | - Dandan Izabel-Shen
- Helmholtz Institute for Functional Marine Biodiversity at the University of Oldenburg (HIFMB), Oldenburg, 26129, Germany; Alfred-Wegener-Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, 27570, Germany.
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12
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Abulaiti A, She D, Pan Y, Shi Z, Hu L, Huang X, Shan J, Xia Y. Drainage ditches are significant sources of indirect N 2O emissions regulated by available carbon to nitrogen substrates in salt-affected farmlands. WATER RESEARCH 2024; 251:121164. [PMID: 38246078 DOI: 10.1016/j.watres.2024.121164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 01/23/2024]
Abstract
Agriculture is a main source of nitrous oxide (N2O) emissions. In agricultural systems, direct N2O emissions from nitrogen (N) addition to soils have been widely investigated, whereas indirect emissions from aquatic ecosystems such as ditches are poorly known, with insufficient data available to refine the IPCC emission factor. In this contribution, in situ N2O emissions from two ditch water‒air interfaces based on a diffusion model were investigated (almost once per month) from June 2021 to December 2022 in an intensive arable catchment with high N inputs and salt-affected conditions in the Qingtongxia Irrigation District, northwestern China. Our results implied that agricultural ditches (mean 148 μg N m-2 h-1) were significant sources for N2O emissions, and were approximately 2.1 times greater than those of the Yellow River directly connected to ditches. Agronomic management strategies increased N2O fluxes in summer, while precipitation events decreased N2O fluxes. Agronomic management strategies, including fertilization (294--540 kg N hm-2) and irrigation on farmland, resulted in enhanced diffuse N loads in drain water, whereas precipitation diluted the dissolved N2O concentration in ditches and accelerated the ditch flow rate, leading to changes in the residence time of N-containing substances in water. The spatial analysis showed that N2O fluxes (202-233 μg N m-2 h-1) in the headstream and upstream regions of ditches due to livestock and aquaculture pollution sources were relatively high compared to those in the midstream and downstream regions (100-114 μg N m-2 h-1). Furthermore, high available carbon (C) relative to N reduced N2O fluxes at low DOC:DIN ratio levels by inhibiting nitrification. Spatiotemporal variations in the N2O emission factor (EF5) across ditches with higher N resulted in lower EF5 and a large coefficient of variation (CV) range. EF5 was 0.0011 for the ditches in this region, while the EF5 (0.0025) currently adopted by the IPCC is relatively high. The EF5 variation was strongly controlled by the DOC:DIN ratio, TN, and NO3--N, while salinity was also a nonnegligible factor regulating the EF5 variation. The regression model incorporating NO3--N and the DOC:DIN ratio could greatly enhance the predictions of EF5 for agricultural ditches. Our study filled a key knowledge gap regarding EF5 from agricultural ditches in salt-affected farmland and offered a field investigation for refining the EF5 currently used by the IPCC.
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Affiliation(s)
- Alimu Abulaiti
- College of Agricultural Science and Engineering, Hohai University, Nanjing 211100, China; Jiangsu Province Engineering Research Center for Agricultural Soil‒Water Efficient Utilization, Carbon Sequestration and Emission Reduction, Nanjing 211100, China
| | - Dongli She
- College of Agricultural Science and Engineering, Hohai University, Nanjing 211100, China; College of Soil and Water Conservation, Hohai University, Changzhou 213200, China.
| | - Yongchun Pan
- College of Agricultural Science and Engineering, Hohai University, Nanjing 211100, China; Jiangsu Province Engineering Research Center for Agricultural Soil‒Water Efficient Utilization, Carbon Sequestration and Emission Reduction, Nanjing 211100, China
| | - Zhenqi Shi
- College of Agricultural Science and Engineering, Hohai University, Nanjing 211100, China; Jiangsu Province Engineering Research Center for Agricultural Soil‒Water Efficient Utilization, Carbon Sequestration and Emission Reduction, Nanjing 211100, China
| | - Lei Hu
- Jiangsu Surveying and Design Institute of Water Resources Co., Ltd., Yangzhou 225002, China
| | - Xuan Huang
- College of Agricultural Science and Engineering, Hohai University, Nanjing 211100, China; Jiangsu Province Engineering Research Center for Agricultural Soil‒Water Efficient Utilization, Carbon Sequestration and Emission Reduction, Nanjing 211100, China
| | - Jun Shan
- Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Yongqiu Xia
- Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
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13
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Wang C, Xv Y, Wu Z, Li X, Li S. Denitrification regulates spatiotemporal pattern of N 2O emission in an interconnected urban river-lake network. WATER RESEARCH 2024; 251:121144. [PMID: 38277822 DOI: 10.1016/j.watres.2024.121144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 01/08/2024] [Accepted: 01/14/2024] [Indexed: 01/28/2024]
Abstract
Urban rivers are hotspots of N2O production and emission. Interconnected river-lake networks are constructed to improve the water quality and hydrodynamic conditions of urban rivers in many cities of China. However, the impact of the river-lake connectivity project on N2O production and emission remains unclear. This study investigated dissolved N2O and emission of the river-lake network in Wuhan City, China from March 2021 to December 2021. The results showed that river-lake connection greatly decreased riverine Nitrogen (N) concentration and increased dissolved oxygen (DO) concentration compare to traditional urban rivers. N2O emissions from the urban river interconnected with lakes (LUR: 67.3 ± 92.6 μmol/m2/d) were much lower than those from the traditional urban rivers (UR: 467.3 ± 1075.7 μmol/m2/d) and agricultural rivers (AR: 20.4 ± 15.3μmol/m2/d). Regression tree analysis suggested that the N2O concentrations were extremely high when hypoxia exists (DO < 1.6 mg/L), and TDN was the primary factor regulating N2O concentrations when hypoxia does not occur. Thus, we ascribe the low N2O emission in the LUR and AR to the lower N contents and higher DO concentrations. The microbial process of N2O production and consumption were quantitatively estimated by isotopic models. The mean proportion of denitrification derived N2O (fbD) was 63.5 %, 55.6 %, 42.3 % and 42.7 % in the UR, LUR, lakes and AR, suggested denitrification dominated N2O production in the urban rivers, but nitrification dominated N2O production in the lakes and AR. The positive correlation between logN2O and fbD suggested that denitrification is the key process to regulate the N2O production and emission. The abundance of denitrification genes (nirS and nirK) was much higher than that of nitrification genes (amoA and amoB), also evidenced that denitrification was the main N2O source. Therefore, river-lake interconnected projects changed the nutrients level and hypoxic condition, leading to the inhibition of denitrification and nitrification, and ultimately resulting in a decrease of N2O production and emission. These results advance the knowledge on the microbial processes that regulate N2O emissions in inland waters and illustrate the integrated management of water quality and N2O emission.
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Affiliation(s)
- Chunlin Wang
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, 206 Guanggu 1st Road, Wuhan 430205, China
| | - Yuhan Xv
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, 206 Guanggu 1st Road, Wuhan 430205, China
| | - Zefeng Wu
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, 206 Guanggu 1st Road, Wuhan 430205, China
| | - Xing Li
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, 206 Guanggu 1st Road, Wuhan 430205, China.
| | - Siyue Li
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, 206 Guanggu 1st Road, Wuhan 430205, China.
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14
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Wang Z, Ruan X, Li R, Zhang Y. Microbial interaction patterns and nitrogen cycling regularities in lake sediments under different trophic conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167926. [PMID: 37863216 DOI: 10.1016/j.scitotenv.2023.167926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 10/05/2023] [Accepted: 10/16/2023] [Indexed: 10/22/2023]
Abstract
Exploring how nitrogen (N) cycling microbes interact in eutrophic lake sediments and how biogenic elements influence the nitrogen cycle is crucial for understanding biogeochemical cycles and nitrogen accumulation mechanisms. In this study, sediment samples were collected from various areas of Taihu Lake with different trophic conditions in all four seasons from 2015 to 2017. Using high-throughput sequencing and molecular ecological network analysis, we investigated the microbial interaction patterns and the role of nitrogen cycling in sediments from lakes with different trophic conditions. The results showed distinct structures of sediment microbial networks between lake areas with different trophic conditions. In the more eutrophic region, network indices indicate higher transfer efficiency of energy, material, and information, more significant competition, and weaker niche differentiation of the microbial community. The sedimentary environment in the moderately eutrophic area exhibited greater potential for denitrification, nitrification, and anammox compared to the mesotrophic area, but the inhibition between N functional microbes and limitations in N removal processes were also more likely to occur. The topological structure of the networks showed that the carbon (C), sulfur (S), and iron (Fe) cycles had a strong influence on the nitrogen cycle in both lake areas. In the moderately eutrophic lake area, C- and S-cycling functional bacteria facilitated a closed cycle of the coupled N fixation-nitrification-DNRA (dissimilatory nitrate reduction to ammonium) process and reduced N removal. In the mesotrophic lake area, C- and S-cycling functional bacteria promoted both N fixation and mineralization, and Fe-cycling functional bacteria coupled with denitrifiers enhanced the nitrogen removal process of products from nitrogen fixation and mineralization. This study improved the understanding of the nitrogen cycling mechanism in lake sediments under different trophic conditions.
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Affiliation(s)
- Ziwei Wang
- Department of Hydrosciences, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China; MOE Key Laboratory of Surficial Geochemistry, Nanjing University, Nanjing 210023, China
| | - Xiaohong Ruan
- Department of Hydrosciences, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China; MOE Key Laboratory of Surficial Geochemistry, Nanjing University, Nanjing 210023, China.
| | - Rongfu Li
- Department of Hydrosciences, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China; MOE Key Laboratory of Surficial Geochemistry, Nanjing University, Nanjing 210023, China
| | - Yaping Zhang
- Department of Hydrosciences, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China; MOE Key Laboratory of Surficial Geochemistry, Nanjing University, Nanjing 210023, China
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15
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Sun H, Tian Y, Zhan W, Zhang H, Meng Y, Li L, Zhou X, Zuo W, Ngo HH. Estimating Yangtze River basin's riverine N 2O emissions through hybrid modeling of land-river-atmosphere nitrogen flows. WATER RESEARCH 2023; 247:120779. [PMID: 37897993 DOI: 10.1016/j.watres.2023.120779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 09/15/2023] [Accepted: 10/22/2023] [Indexed: 10/30/2023]
Abstract
Riverine ecosystems are a significant source of nitrous oxide (N2O) worldwide, but how they respond to human and natural changes remains unknown. In this study, we developed a compound model chain that integrates mechanism-based modeling and machine learning to understand N2O transfer patterns within land, rivers, and the atmosphere. The findings reveal a decrease in N2O emissions in the Yangtze River basin from 4.7 Gg yr-1 in 2000 to 2.8 Gg yr-1 in 2019, with riverine emissions accounting for 0.28% of anthropogenic nitrogen discharges from land. This unexpected reduction is primarily attributed to improved water quality from human-driven nitrogen control, while natural factors contributed to a 0.23 Gg yr-1 increase. Notably, urban rivers exhibited a more rapid N2O efflux ( [Formula: see text] ), with upstream levels nearly 3.1 times higher than rural areas. We also observed nonlinear increases in [Formula: see text] with nitrogen discharge intensity, with urban areas showing a gradual and broader range of increase compared to rural areas, which exhibited a sharper but narrower increase. These nonlinearities imply that nitrogen control measures in urban areas lead to stable reductions in N2O emissions, while rural areas require innovative nitrogen source management solutions for greater benefits. Our assessment offers fresh insights into interpreting riverine N2O emissions and the potential for driving regionally differentiated emission reductions.
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Affiliation(s)
- Huihang Sun
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Yu Tian
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Wei Zhan
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Haoran Zhang
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Yiming Meng
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Lipin Li
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Xue Zhou
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Wei Zuo
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Huu Hao Ngo
- Faculty of Engineering, University of Technology Sydney, P.O. Box 123, Broadway, Sydney, NSW 2007, Australia
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16
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Yeerken S, Li L, Deng M, Song K, Wu F. Effect and microbial mechanism of suspended sediments particle size on nitrous oxide emission in eutrophic lakes. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 334:122180. [PMID: 37442329 DOI: 10.1016/j.envpol.2023.122180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 07/04/2023] [Accepted: 07/10/2023] [Indexed: 07/15/2023]
Abstract
Suspended sediment (SPS) is an important environmental factor in eutrophic lakes, where they may play a significant role in the microbial nitrogen cycle and thus affect the N2O source and sink function. This study investigated the correlation and corresponding microbial mechanisms between N2O emission fluxes and SPS particle sizes. N2O emission characteristics were investigated in four parallel operated lab-scale microcosmic systems, in which different sizes of SPS particles were inoculated (i.e., <75, 75-150, 150-300, and >300 μm). The results show that, N2O emission fluxes in the eutrophic lakes were exponentially correlated with the lake trophic level index (TLI) (R2 = 0.94, p < 0.01) and the specific surface area of the SPS (R2 = 0.38, p < 0.05). In the microcosmic systems, SPS with 75-150 μm particles had the highest N2O emission rate of 5.94 ± 0.007 μg N/L/d, which was 2.6 times that of the <75 μm particle size system. The microcosmic system with particle size >300 μm had the highest N2O reduction rate (Vmax) of 6.776 μmol/L/h, which was 16-50 times that of the other three groups. Larger particle size SPS have a smaller specific surface area, which could affect the microenvironment on SPS surface and thus affect the microbe functions. The microbial community structure results indicated that the dominant microorganisms on the SPS surface were denitrifying bacteria. The maximum (nirS + nirK)/nosZ ratio was 30.2 for the 75-150 μm system, which was nearly 2 times higher than the other systems. The >300 μm system had the highest nosZ abundance, indicating a strong ability to reduce N2O. The co-occurrence networks analysis indicated that the cooperation and competition among nitrifiers and denitrifiers determined N2O emissions. These results provide fundamental insights into the influence of SPS size on N2O emissions in eutrophic lakes.
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Affiliation(s)
- Senbati Yeerken
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-Environmental Science & Technology, Guangdong Academy of Sciences, Guangzhou, 510650, China
| | - Lu Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Min Deng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Kang Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, 430072, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Fengchang Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
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17
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Cheng X, Dong Y, Fan F, Xiao S, Liu J, Wang S, Lin W, Zhou C. Shifts in the high-resolution spatial distribution of dissolved N 2O and the underlying microbial communities and processes in the Pearl River Estuary. WATER RESEARCH 2023; 243:120351. [PMID: 37517146 DOI: 10.1016/j.watres.2023.120351] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 07/05/2023] [Accepted: 07/11/2023] [Indexed: 08/01/2023]
Abstract
Estuaries are significant sources of the ozone-depleting greenhouse gas N2O. However, owing to large spatial heterogeneity and discrete measurements, N2O emissions from estuaries are considerably uncertain. Microbial processes are disputed in terms of the dominant N2O production under severe human disturbance. Herein, combining real-time and high-resolution measurements with bioinformatics analysis, we accurately mapped the consecutive two-dimensional N2O distribution in the Pearl River Estuary (PRE), China, and revealed its underlying microbial mechanisms. Both the horizontal and vertical distributions of N2O concentrations varied greatly at fine scales. Supersaturated N2O concentrations (9.1 to 132.2 nmol/L) in the surface water decreased along the estuarine salinity gradient, with several emission hotspots scattering upstream. The vertical N2O distribution showed marked differences from complete mixing upstream to incomplete mixing downstream, with constant or changeable concentrations with increasing depth. Furthermore, spatially varied denitrifying and nitrifying microorganisms controlled the N2O production and distribution in the PRE, with denitrification playing the dominant role. The nirK-type and nirS-type denitrifying bacteria were the primary producers of N2O in the water and sediment columns, respectively. In addition, substrate concentration (NO3- and DOC) regulated N2O production by affecting key microbial processes, while physical influences (water-mass mixing and salt wedges) reshaped N2O distribution. With these information, a conceptual model of estuarine N2O production and distribution was constructed to generalize the possible biochemical processes under environmental constraints, which could provide insights into the N2O biogeochemical cycle and emission mitigation from a mechanistic perspective.
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Affiliation(s)
- Xiang Cheng
- Guangdong-Hong Kong Joint Laboratory for Water Security, Beijing Normal University, Zhuhai 519087, China; Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Yue Dong
- Guangdong-Hong Kong Joint Laboratory for Water Security, Beijing Normal University, Zhuhai 519087, China; Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China.
| | - Fuqiang Fan
- Guangdong-Hong Kong Joint Laboratory for Water Security, Beijing Normal University, Zhuhai 519087, China; Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China
| | - Shangbin Xiao
- College of Hydraulic and Environment Engineering, China Three Gorges University, Yichang 443002, China; Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir, China Three Gorges University, Yichang 443002, China
| | - Jia Liu
- College of Water Sciences, Beijing Normal University, Beijing 100875, China; Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir, China Three Gorges University, Yichang 443002, China
| | - Shengrui Wang
- Guangdong-Hong Kong Joint Laboratory for Water Security, Beijing Normal University, Zhuhai 519087, China; Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Wei Lin
- Guangdong-Hong Kong Joint Laboratory for Water Security, Beijing Normal University, Zhuhai 519087, China; Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China
| | - Chunyang Zhou
- Guangdong-Hong Kong Joint Laboratory for Water Security, Beijing Normal University, Zhuhai 519087, China; Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China
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18
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Yan R, Wang F, Wang Y, Chen N. Pollution abatement reducing the river N 2O emissions although it is partially offset by a warming climate: Insights from an urbanized watershed study. WATER RESEARCH 2023; 236:119934. [PMID: 37043873 DOI: 10.1016/j.watres.2023.119934] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 03/15/2023] [Accepted: 03/31/2023] [Indexed: 06/19/2023]
Abstract
Global nitrogen (N) pollution has resulted in increased river nitrous oxide (N2O) emissions, which contribute to climate change. However, little is known about how pollution abatement conversely reduces river N2O production in a warming climate. Here, field observations and microcosmic experiments were conducted in a coastal urbanized watershed (S.E. China) to explore the interactive effect of changing nitrate and temperature on river sediment denitrification (DNF) and N2O production. The results showed that urban river reaches (UR) with higher organic carbon content and denitrifying gene abundance in sediments have a greater DNF rate, nitrate removal efficiency (NRE), and N2O concentration than agricultural river reaches (AR). Microcosmic incubation suggested that the DNF rate and associated N2O production decreased under low nitrate addition, wherein the NRE increased. The scenario simulation illustrated a nonlinear response of N2O production to nitrate removal (i.e., ΔN2O/ΔNO3-N) from both UR and AR sediments at a given temperature, and the DNF rate and N2O production increased with increasing temperature. An increase in temperature by 1 degree Celsius would offset 18.75% of the N2O reduction by nitrate removal via DNF. These findings implied that watershed pollution abatement undoubtedly contributes to the reduction in global river N2O emissions although it is partially offset by extra N2O production caused by global warming.
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Affiliation(s)
- Ruifeng Yan
- Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, College of the Environment and Ecology, Xiamen University, Xiamen, 361102, China
| | - Fenfang Wang
- Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, College of the Environment and Ecology, Xiamen University, Xiamen, 361102, China; State Key Laboratory of Marine Environment Science, Xiamen University, Xiamen, 361102, China
| | - Yao Wang
- Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, College of the Environment and Ecology, Xiamen University, Xiamen, 361102, China
| | - Nengwang Chen
- Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, College of the Environment and Ecology, Xiamen University, Xiamen, 361102, China; State Key Laboratory of Marine Environment Science, Xiamen University, Xiamen, 361102, China.
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19
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Zhou Y, Lian Y, Liu T, Jin X, Wang Z, Liu X, Zhou M, Jing D, Yin W, Feng J, Wang H, Zhang D. Impacts of high-quality coal mine drainage recycling for replenishment of aquatic ecosystems in arid regions of China: Bacterial community responses. ENVIRONMENTAL RESEARCH 2023; 223:115083. [PMID: 36529333 DOI: 10.1016/j.envres.2022.115083] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/05/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
Coal mine water is usually recycled as supplementary water for aquatic ecosystems in arid and semiarid mining regions of China. To ensure ecosystem health, the coal mine water is rigorously treated using several processes, including reverse osmosis, to meet surface water quality standards. However, the potential environmental impacts of this management pattern on the ecological function of receiving water bodies are unclear. In this study, we built several microcosm water ecosystems to simulate the receiving water bodies. High-quality treated coal mine drainage was mixed into the model water bodies at different concentrations, and the sediment bacterial community response and functional changes were systematically investigated. The results showed that the high-quality coal mine drainage could still shape bacterial taxonomic diversity, community composition and structure, with a concentration threshold of approximately 50%. Moreover, both the Mantel test and the structural equation model indicated that the salinity fluctuation caused by the receiving of coal mine drainage was the primary factor shaping the bacterial communities. 10 core taxa in the molecular ecological network influenced by coal mine drainage were identified, with the most critical taxa being patescibacteria and g_Geothermobacter. Furthermore, the pathway of carbohydrate metabolism as well as signaling molecules and interactions was up-regulated, whereas amino acid metabolism showed the opposite trend. All results suggested that the complex physical-chemical and biochemical processes in water ecosystems may be affected by the coal mine drainage. The bacterial community response and underlying functional changes may accelerate internal nutrient cycling, which may have a potential impact on algal bloom outbreaks.
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Affiliation(s)
- Yaqian Zhou
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou, Jiangsu, 215009, PR China
| | - Ying Lian
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Tengxiang Liu
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Xian Jin
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Zhigang Wang
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Xin Liu
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Mengling Zhou
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Dan Jing
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Weiwen Yin
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Jiaying Feng
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Heli Wang
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing, 100083, PR China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou, Jiangsu, 215009, PR China.
| | - Daxin Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing, 100083, PR China; School of Soil & Water Conservation, Beijing Forestry University, Beijing, 100083, PR China.
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20
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Li X, Xu YJ, Ni M, Wang C, Li S. Riverine nitrate source and transformation as affected by land use and land cover. ENVIRONMENTAL RESEARCH 2023; 222:115380. [PMID: 36716803 DOI: 10.1016/j.envres.2023.115380] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 01/24/2023] [Accepted: 01/26/2023] [Indexed: 06/18/2023]
Abstract
A mixed land use/land cover (LULC) catchment increases the complexity of sources and transformations of nitrate in rivers. Spatial paucity of sampling particularly low-resolution sampling in tributaries can result in a bias for identifying nitrate sources and transformations. In this study, high spatial resolution sampling campaigns covering mainstream and tributaries in combination with hydro-chemical parameters and dual isotopes of nitrate were performed to reveal spatio-temporal variations of nitrate sources and transformations in a river draining a mixed LULC catchment. This study suggested that point sources dominated the nitrate in the summer and winter, while non-point sources dominated the nitrate in the spring and autumn. A positive correlation was observed between proportions from sewage and land use index (LUI). However, negative correlations between soil nitrogen/nitrogen fertilizer and LUI were observed. With an increase of urban areas, the increased contribution from domestic sewage resulted in an increase of NO3- concentrations in rivers. Both urban and agricultural inputs should be considered in nitrate pollution management in a mixed LULC catchment. We concluded that the seasonal variations of nitrate sources were mainly affected by flow velocity conditions and agricultural activities, while spatial variations were mainly affected by LULC. In addition, we found a novel underestimation of dominated sources from Bayesian model because of mixing effect of isotope values from the tributaries to mainstream, however, high spatial resolution sampling can make up for this shortcoming. δ15N and δ18O values of nitrate indicated that nitrate originated from nitrification in soils. The nitrate concentrations and correlation between δ15N and 1/[NO3-] suggested little contribution of nitrate removal by denitrification. Thus, the nitrate reduction in the Yuehe River basin needs to be strengthened. The study provides new implications for estimation of nitrate sources and transformations and basis for nitrate reduction in the river with mixed LULC catchment.
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Affiliation(s)
- Xing Li
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, Wuhan, 430205, China
| | - Y Jun Xu
- School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, LA, 70803, USA; Coastal Studies Institute, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Maofei Ni
- College of Eco-environmental Engineering, Guizhou Minzu University, Guiyang, China
| | - Chunlin Wang
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, Wuhan, 430205, China
| | - Siyue Li
- Institute of Changjiang Water Environment and Ecological Security, School of Environmental Ecology and Biological Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, Wuhan Institute of Technology, Wuhan, 430205, China.
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21
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Xing CY, Li H, Li Q, Lu LH, Li Z. Shifts in composition and function of bacterial communities reveal the effect of small barriers on nitrous oxide and methane accumulation in fragmented rivers. Front Microbiol 2023; 14:1110025. [PMID: 36896435 PMCID: PMC9990636 DOI: 10.3389/fmicb.2023.1110025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/30/2023] [Indexed: 02/23/2023] Open
Abstract
Rivers are often blocked by barriers to form different habitats, but it is not clear whether this change will affect the accumulation of N2O and CH4 in rivers. Here, low barriers (less than 2 m, LB) increased N2O concentration by 1.13 times and CH4 decreased by 0.118 times, while high barriers (higher than 2 m, less than 5 m high, HB) increased N2O concentration by 1.19 times and CH4 by 2.76 times. Co-occurrence network analysis indicated LB and HB can promote the enrichment of Cyanobium and Chloroflexi, further limiting complete denitrification and increasing N2O accumulation. The LB promotes methanotrophs (Methylocystis, Methylophilus, and Methylotenera) to compete with denitrifiers (Pseudomonas) in water, and reduce CH4 accumulation. While the HB can promote the methanotrophs to compete with nitrifiers (Nitrosospira) in sediment, thus reducing the consumption of CH4. LB and HB reduce river velocity, increase water depth, and reduce dissolved oxygen (DO), leading to enrichment of nirS-type denitrifiers and the increase of N2O concentration in water. Moreover, the HB reduces DO concentration and pmoA gene abundance in water, which can increase the accumulation of CH4. In light of the changes in the microbial community and variation in N2O and CH4 accumulation, the impact of fragmented rivers on global greenhouse gas emissions merits further study.
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Affiliation(s)
- Chong-Yang Xing
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institutes of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.,Chongqing School, University of Chinese Academy of Sciences, Chongqing, China
| | - Hang Li
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institutes of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.,Chongqing School, University of Chinese Academy of Sciences, Chongqing, China
| | - Qi Li
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institutes of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.,Chongqing School, University of Chinese Academy of Sciences, Chongqing, China
| | - Lun-Hui Lu
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institutes of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.,Chongqing School, University of Chinese Academy of Sciences, Chongqing, China
| | - Zhe Li
- Key Laboratory of Reservoir Aquatic Environment, Chongqing Institutes of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.,Chongqing School, University of Chinese Academy of Sciences, Chongqing, China
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22
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Shu W, Wang P, Zhao J, Ding M, Zhang H, Nie M, Huang G. Sources and migration similarly determine nitrate concentrations: Integrating isotopic, landscape, and biological approaches. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 852:158216. [PMID: 36028031 DOI: 10.1016/j.scitotenv.2022.158216] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 08/04/2022] [Accepted: 08/18/2022] [Indexed: 06/15/2023]
Abstract
Rapid land use change has significantly increased nitrate (NO3-) loading to rivers, leading to eutrophication, and posing water security problems. Determining the sources of NO3- to waters and the underlying influential factors is critical for effectively reducing pollution and better managing water resources. Here, we identified the sources and influencing mechanisms of NO3- in a mixed land-use watershed by integrating stable isotopes (δ15N-NO3- and δ18O-NO3-), molecular biology, water chemistry, and landscape metrics measurements. Weak transformation processes of NO3- were identified in the river, as evinced by water chemistry, isotopes, species compositions, and predicted microbial genes related to nitrogen metabolism. NO3- concentrations were primarily influenced by exogenous inputs (i.e., from soil nitrogen (NS), nitrogen fertilizer (NF), and manure & sewage (MS)). The proportions of NO3- sources seasonally varied. In the wet season, the source contributions followed the order of NS (38.6 %) > NF (31.4 %) > atmospheric deposition (ND, 16.2 %) > MS (13.8 %). In the dry season, the contributions were in the order of MS (39.2 %) > NS (29.2 %) > NF (29 %) > ND (2.6 %). Farmland and construction land were the original factors influencing the spatial distribution of NO3- in the wet and dry seasons, respectively, while slope, basin relief (HD), hypsometric integral (HI), and COHESION, HD were the primary indicators associated with NO3- transport in the wet and dry seasons, respectively. Additionally, spatial scale differences were observed for the effects of landscape structure on NO3- concentrations, with the greatest effect at the 1000-m buffer zone scale in the wet season and at the sub-basin scale in the dry season. This study overcomes the limitation of isotopes in identifying nitrate sources by combining multiple approaches and provides new research perspectives for the determination of nitrate sources and migration in other watersheds.
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Affiliation(s)
- Wang Shu
- School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, Jiangxi, China; Sino-Danish College of University of Chinese Academy of Sciences, Beijing 101408, China; Sino-Danish Centre for Education and Research, Beijing 101408, China
| | - Peng Wang
- School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, Jiangxi, China.
| | - Jun Zhao
- School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
| | - Minjun Ding
- School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Hua Zhang
- School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Minghua Nie
- School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
| | - Gaoxiang Huang
- School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, Jiangxi, China
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23
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Liang X, Wang B, Gao D, Han P, Zheng Y, Yin G, Dong H, Tang Y, Hou L. Nitrification Regulates the Spatiotemporal Variability of N 2O Emissions in a Eutrophic Lake. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:17430-17442. [PMID: 36347244 DOI: 10.1021/acs.est.2c03992] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Nitrous oxide (N2O) emissions from lakes exhibit significant spatiotemporal heterogeneity, and quantitative identification of the different N2O production processes is greatly limited, causing the role of nitrification to be undervalued or ignored in models of a lake's N2O emissions. Here, the contributions of nitrification and denitrification to N2O production were quantitatively assessed in the eutrophic Lake Taihu using molecular biology and isotope mapping techniques. The N2O fluxes ranged from -41.48 to 28.84 μmol m-2 d-1 in the lake, with lower N2O concentrations being observed in spring and summer and significantly higher N2O emissions being observed in autumn and winter. The 15N site preference and relevant isotopic evidence demonstrated that denitrification contributed approximately 90% of the lake's gross N2O production during summer and autumn, 27-83% of which was simultaneously eliminated via N2O reduction. Surprisingly, nitrification seemed to act as a key process promoting N2O production and contributing to the lake as a source of N2O emissions. A combination of N2O isotopocule-based approaches and molecular techniques can be used to determine the precise characteristics of microbial N2O production and consumption in eutrophic lakes. The results of this study provide a basis for accurately assessing N2O emissions from lakes at the regional and global scales.
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Affiliation(s)
- Xia Liang
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai200241, People's Republic of China
| | - Baoli Wang
- Institute of Surface-Earth System Science, Tianjin University, Tianjin300072, People's Republic of China
| | - Dengzhou Gao
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai200241, People's Republic of China
| | - Ping Han
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai200241, People's Republic of China
- School of Geographic Sciences, East China Normal University, Shanghai200241, People's Republic of China
| | - Yanling Zheng
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai200241, People's Republic of China
- School of Geographic Sciences, East China Normal University, Shanghai200241, People's Republic of China
| | - Guoyu Yin
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai200241, People's Republic of China
- School of Geographic Sciences, East China Normal University, Shanghai200241, People's Republic of China
| | - Hongpo Dong
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai200241, People's Republic of China
| | - Yali Tang
- Engineering Research Center for Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou510632, People's Republic of China
| | - Lijun Hou
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai200241, People's Republic of China
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24
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Wang J, Wang G, Zhang S, Xin Y, Jiang C, Liu S, He X, McDowell WH, Xia X. Indirect nitrous oxide emission factors of fluvial networks can be predicted by dissolved organic carbon and nitrate from local to global scales. GLOBAL CHANGE BIOLOGY 2022; 28:7270-7285. [PMID: 36176238 DOI: 10.1111/gcb.16458] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 09/23/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Streams and rivers are important sources of nitrous oxide (N2 O), a powerful greenhouse gas. Estimating global riverine N2 O emissions is critical for the assessment of anthropogenic N2 O emission inventories. The indirect N2 O emission factor (EF5r ) model, one of the bottom-up approaches, adopts a fixed EF5r value to estimate riverine N2 O emissions based on IPCC methodology. However, the estimates have considerable uncertainty due to the large spatiotemporal variations in EF5r values. Factors regulating EF5r are poorly understood at the global scale. Here, we combine 4-year in situ observations across rivers of different land use types in China, with a global meta-analysis over six continents, to explore the spatiotemporal variations and controls on EF5r values. Our results show that the EF5r values in China and other regions with high N loads are lower than those for regions with lower N loads. Although the global mean EF5r value is comparable to the IPCC default value, the global EF5r values are highly skewed with large variations, indicating that adopting region-specific EF5r values rather than revising the fixed default value is more appropriate for the estimation of regional and global riverine N2 O emissions. The ratio of dissolved organic carbon to nitrate (DOC/NO3 - ) and NO3 - concentration are identified as the dominant predictors of region-specific EF5r values at both regional and global scales because stoichiometry and nutrients strictly regulate denitrification and N2 O production efficiency in rivers. A multiple linear regression model using DOC/NO3 - and NO3 - is proposed to predict region-specific EF5r values. The good fit of the model associated with easily obtained water quality variables allows its widespread application. This study fills a key knowledge gap in predicting region-specific EF5r values at the global scale and provides a pathway to estimate global riverine N2 O emissions more accurately based on IPCC methodology.
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Affiliation(s)
- Junfeng Wang
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
| | - Gongqin Wang
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
- Hebei Key Laboratory of Close-to-Nature Restoration Technology of Wetlands, School of Eco-Environment, Hebei University, Baoding, Hebei, China
| | - Sibo Zhang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou, China
| | - Yuan Xin
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
| | - Chenrun Jiang
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
| | - Shaoda Liu
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
| | - Xiaojia He
- The Administrative Center for China's Agenda 21, Beijing, China
| | - William H McDowell
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire, USA
| | - Xinghui Xia
- Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, China
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25
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Li L, Li F, Deng M, Wu C, Zhao X, Song K, Wu F. Microplastics distribution characteristics in typical inflow rivers of Taihu lake: Linking to nitrous oxide emission and microbial analysis. WATER RESEARCH 2022; 225:119117. [PMID: 36126427 DOI: 10.1016/j.watres.2022.119117] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 09/06/2022] [Accepted: 09/12/2022] [Indexed: 06/15/2023]
Abstract
The microplastics in nature water are important for the environmental fate of nitrous oxide (N2O). This study investigated the influence and microbial mechanism of microplastic abundance to the N2O flux in typical inflow rivers of Taihu lake. The microplastic abundance were in a range of 160-700 particles/m3 surface water, and 514-3018 particles/kg dry sediment. The highest percentage of microplastic color was transparent, significantly higher than other color (p<0.0001) in both surface water and sediment. The dominant microplastic size was 500-5000 μm in surface water, while size lower than 1000 μm was dominant in sediment. The microplastic abundance in sediment was negatively correlated with the concentration of suspended sediments (SPS) (p<0.05), Chl-a (p<0.05), NH4+-N (p<0.05) and TP (p<0.01) in inflow river surface water. The dissolved N2O concentration were 45.71-132.42 nmol/L, and the N2O fluxes were 29.85-276.60 μmol/m2/d. The dissolved N2O concentration was significantly correlated with the nirK abundance and nirK/nosZI ratio negatively (p<0.05), revealed that sediment nirK-type denitrification was the main driver of dissolved N2O. Meanwhile, the N2O flux (water-air interface) was significantly correlated with nosZI, napA, narG and nirS negatively, implied that nitrification and denitrification interaction in sediment is the main influence factor. The denitrification process in sediment was the main driven factor of N2O releasing. Mantel-test shows that microplastic abundance in surface water was significantly correlated with nitrification (p = 0.001∼0.01) and denitrification (p = 0.01∼0.05) genera in water. The dominant denitrification microorganism was Dechloromonas in sediment and Flavobacterium in surface water. These results provided new insight into the fact that plastisphere which comprises microbial community on microplastic could affect the N2O emission in aquatic system.
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Affiliation(s)
- Lu Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Fangbai Li
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Guangdong Institute of Eco-Environmental Science & Technology, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Min Deng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Chenxi Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaoli Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Kang Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Fengchang Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
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Li H, Wei Z, Song C, Chen X, Zhang R, Liu Y. Functional keystone drive nitrogen conversion during different animal manures composting. BIORESOURCE TECHNOLOGY 2022; 361:127721. [PMID: 35914672 DOI: 10.1016/j.biortech.2022.127721] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/26/2022] [Accepted: 07/27/2022] [Indexed: 06/15/2023]
Abstract
In this study, nitrogen transformation of chicken manure (CM) and cattle dung (CD) during composting was analyzed and its related functional keystones were identified. The results showed that chicken manure showed more severe nitrogen conversion during composting. The main N conversion factors in cattle dung were nitrite nitrogen (NO2--N) and ammonium nitrogen (NH4+-N), while the main N conversion factors in chicken manure were NH4+-N and nitrate nitrogen (NO3--N). The nitrogen-transforming bacterial community in chicken manure was more diverse. Variations in functional keystone abundances in cattle dung tended to be confined to the cooling and maturation periods, whereas changes in chicken manure persisted throughout the composting process. Environmental factors affected the functional keystones of nitrogen transformation. This study may provide directions for regulating nitrogen conversion in animal manure composting.
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Affiliation(s)
- Huiying Li
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Zimin Wei
- College of Life Science, Northeast Agricultural University, Harbin 150030, China.
| | - Caihong Song
- College of Life Science, Liaocheng University, Liaocheng 252000, China
| | - Xiaomeng Chen
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Ruju Zhang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Yumeng Liu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
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27
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Xuan Y, Mai Y, Xu Y, Zheng J, He Z, Shu L, Cao Y. Enhanced microbial nitrification-denitrification processes in a subtropical metropolitan river network. WATER RESEARCH 2022; 222:118857. [PMID: 35868099 DOI: 10.1016/j.watres.2022.118857] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 07/09/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Urban rivers are hotspots of regional nitrogen (N) pollution and N transformations. Previous studies have reported that the microbial community of urban rivers was different from that of natural rivers. However, how microbial community affects N transformations in the urban rivers is still unclear. In this study, we employed N nutrients-related isotope technology (includes natural-abundance isotopes survey and isotope-labeling method) and bioinformatics methods (includes 16S rRNA high-throughput sequencing and quantitative PCR analysis) to investigate the major N transformations, microbial communities as well as functional gene abundances in a metropolitan river network. Our results suggested that the bacterial community structure in the highly urbanized rivers was characterized by higher richness, less complexity and increased abundances of nitrification and denitrifying bacterium compared to those in the suburban rivers. These differences were mainly caused by high sewage discharge and N loadings. In addition, the abundances of nitrifier gene (amoA) and denitrifier genes (nirK and nirS) were significantly higher in the highly urbanized rivers (2.36 × 103, 7.43 × 107 and 2.28 × 107 copies·mL-1) than that in the suburban rivers (0.43 × 103, 2.18 × 107 and 0.99 × 107 copies·mL-1). These changes in microbes have accelerated nitrification-denitrification processes in the highly urbanized rivers as compared to those in the suburban rivers, which was evidenced by environmental isotopes and the rates of nitrification (10.52 vs. 0.03 nmol·L-1·h-1) and denitrification (83.31 vs. 22.49 nmol·g-1·h-1). Overall, this study concluded that the excess exogenous N has significantly shaped the specific aquatic bacterial communities, which had a potential for enhancing nitrification-denitrification processes in the highly urbanized river network. This study provides a further understanding of microbial N cycling in urban river ecosystems and expands the combined application of isotopic technology and bioinformatics methods in studying biogeochemical cycling.
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Affiliation(s)
- Yingxue Xuan
- School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510006, China
| | - Yingwen Mai
- School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, China
| | - Yunqiu Xu
- School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, China
| | - Jianyi Zheng
- School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, China
| | - Zhili He
- School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510006, China
| | - Longfei Shu
- School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510006, China.
| | - Yingjie Cao
- School of Environmental Science and Engineering, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Guangzhou 510006, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510006, China.
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