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Chen ZL, Yi Y, Fu W, Liang W, Li P, Wang K, Zhang L, Dong K, Li SL, Xu S, He D. Severe flood modulates the sources and age of dissolved organic carbon in the Yangtze River Estuary. ENVIRONMENTAL RESEARCH 2024; 252:119040. [PMID: 38692424 DOI: 10.1016/j.envres.2024.119040] [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: 03/25/2024] [Accepted: 04/27/2024] [Indexed: 05/03/2024]
Abstract
Floods in global large rivers modulate the transport of dissolved organic carbon (DOC) and estuarine hydrological characteristics significantly. This study investigated the impact of a severe flood on the sources and age of DOC in the Yangtze River Estuary (YRE) in 2020. Comparing the flood period in 2020 to the non-flood period in 2017, we found that the flood enhanced the transport of young DOC to the East China Sea (ECS), resulting in significantly enriched Δ14C-DOC values. During the flood period, the proportion of modern terrestrial organic carbon (OC) was significantly higher compared to the non-flood period. Conversely, the proportion of pre-aged sediment OC was significantly lower during the flood period. The high turbidity associated with the flood facilitated rapid transformation and mineralization of sedimentary and fresh terrestrial OC, modifying the sources of DOC. The flux of modern terrestrial OC transported to the ECS during the flood period was 1.58 times higher than that of the non-flood period. These findings suggest that floods can modulate the sources and decrease the age of DOC, potentially leading to increased greenhouse gas emissions. Further research is needed to understand the long-term impacts of floods on DOC dynamics in global estuaries.
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Affiliation(s)
- Zhao Liang Chen
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories, 999077, Hong Kong, China
| | - Yuanbi Yi
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories, 999077, Hong Kong, China.
| | - Wenjing Fu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ocean University of China, Qingdao, 266100, China
| | - Wenzhao Liang
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories, 999077, Hong Kong, China
| | - Penghui Li
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519080, China
| | - Kai Wang
- Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Lixin Zhang
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Kejun Dong
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Si-Liang Li
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Sheng Xu
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Ding He
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories, 999077, Hong Kong, China; State Key Laboratory of Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, 999077, Hong Kong, China.
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2
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Liu X, Lan C, Zhu L, Yan C, Wang N, Chen H, Zheng G, Che Y, Yang Z, Bao R. Sediment resuspension as a driving force for organic carbon transference and rebalance in marginal seas. WATER RESEARCH 2024; 257:121672. [PMID: 38705064 DOI: 10.1016/j.watres.2024.121672] [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: 03/09/2024] [Revised: 04/22/2024] [Accepted: 04/23/2024] [Indexed: 05/07/2024]
Abstract
The transfer of particulate organic carbon (POC) to dissolved organic carbon (DOC; OC transferP-D) is crucial for the marine carbon cycle. Sediment resuspension driven by hydrodynamic forcing can affect the burial of sedimentary POC and benthic biological processes in marginal sea. However, the role of sediment grain size fraction on OC transferP-D and the subsequent impact on OC cycling remain unknown. Here, we conduct sediment resuspension simulations by resuspending grain-size fractionated sediments (< 20, 20-63, and > 63 μm) into filtered seawater, combined with analyses of OC content, optical characteristics, 13C and 14C isotope compositions, and molecular dynamics simulations to investigate OC transferP-D and its regulations on OC bioavailability under sediment resuspension. Our results show that the relative intensities of terrestrial humic-like OC (refractory DOC) increase in resuspension experiments of < 20, 20-63, and > 63 μm sediments by 0.14, 0.01, and 0.03, respectively, likely suggesting that sediment resuspension drives refractory DOC transfer into seawater. The variations in the relative intensities of microbial protein-like DOC are linked to the change of terrestrial humic-like OC, accompanied by higher DOC content and reactivity in seawater, particularly in finer sediments resuspension experiments. This implies that transferred DOC likely fuels microbial growth, contributing to the subsequent enhancement of DOC bioavailability in seawater. Our results also show that the POC contents increase by 0.35 %, 0.66 %, and 0.93 % in < 20, 20-63, and > 63 μm resuspension experiments at the end of incubation, respectively. This suggests that the re-absorption of OC on particles may be a significant process, but previously unrecognized during sediment resuspension. Overall, our findings suggest that sediment resuspension promotes the OC transferP-D, and the magnitudes of OC transferP-D further influence the DOC and POC properties by inducing microbial production and respiration. These processes significantly affect the dynamics and recycling of biological carbon pump in shallow marginal seas.
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Affiliation(s)
- Xiaoqing Liu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Geology, Qingdao Marine Science and Technology Center, Qingdao 266237, China
| | - Chunyuan Lan
- School of Earth and Space Sciences, Peking University, Beijing 100871, China
| | - Longhai Zhu
- College of Marine Geo-Science, Ocean University of China, Qingdao 266100, China; Key Lab of Submarine Geosciences and Prospecting Techniques, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Caiqing Yan
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Nan Wang
- Key Lab of Submarine Geosciences and Prospecting Techniques, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Haibiao Chen
- Environment Research Institute, Shandong University, Qingdao 266237, China
| | - Guangjin Zheng
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Geology, Qingdao Marine Science and Technology Center, Qingdao 266237, China
| | - Yangli Che
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Geology, Qingdao Marine Science and Technology Center, Qingdao 266237, China
| | - Zuosheng Yang
- College of Marine Geo-Science, Ocean University of China, Qingdao 266100, China; Key Lab of Submarine Geosciences and Prospecting Techniques, Ministry of Education, Ocean University of China, Qingdao 266100, China
| | - Rui Bao
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Geology, Qingdao Marine Science and Technology Center, Qingdao 266237, China.
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3
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Yan Z, Lv J, Yi Y, Ma X, Zhang G, Wang S, Zeng X, Jia Y. Molecular composition and characteristics of Sediment-adsorbed Dissolved Organic Matter (SDOM) along the coast of China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 928:172134. [PMID: 38583612 DOI: 10.1016/j.scitotenv.2024.172134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/14/2024] [Accepted: 03/29/2024] [Indexed: 04/09/2024]
Abstract
Sediment-adsorbed Dissolved Organic Matter (SDOM) in coast plays a crucial role in the terrestrial and marine carbon cycle processes of the global environment. However, understanding the transport dynamics of SDOM along the coast of China, particularly its interactions with sediments, remains elusive. In this study, we analyzed the δ13C and δ15N stable isotopic compositions, as well as the molecular characteristics of SDOM collected from coastal areas spanning the Bohai Sea (BS), Yellow Sea (YS), East China Sea (ECS), and South China Sea (SCS), by using isotope ratio mass spectrometry and Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS). We identified the predominant sources of carbon and nitrogen in coastal sediments, revealing terrigenous origins for most C and N, while anthropogenic sources dominated in the SCS. Spatial variations in SDOM chemodiversity were observed, with diverse molecular components influenced by distinct environmental factors and sediment sources. Notably, lignins and saturated compounds (such as proteins/amino sugars) were the predominant molecular compounds detected in coastal SDOM. Through Mantel tests and Spearman's correlation analysis, we elucidated the significant influence of spatial environmental factors (temperature, DO, salinity, and depth) and sediment sources on SDOM molecular chemodiversity. These findings contribute to a more comprehensive understanding of the carbon cycle dynamics along the Chinese coast.
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Affiliation(s)
- Zelong Yan
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jitao Lv
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuanbi Yi
- Department of Ocean Science and the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong, Hong Kong SAR 00852, China
| | - Xu Ma
- College of Environment and Resources, Dalian Minzu University, Dalian, Liaoning 116600, China
| | - Guoqing Zhang
- Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control, Ministry of Education, School of Environment, Henan Normal University, Xinxiang 453007, China
| | - Shaofeng Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
| | - Xiangfeng Zeng
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
| | - Yongfeng Jia
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
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4
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Liu Y, Li M, Ren D, Li Y. Spatial distribution of sediment dissolved organic matter in oligotrophic lakes and its binding characteristics with Pb(II) and Cu(II). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:43369-43380. [PMID: 38902445 DOI: 10.1007/s11356-024-34043-w] [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: 03/21/2024] [Accepted: 06/16/2024] [Indexed: 06/22/2024]
Abstract
Dissolved organic matter (DOM), the most active component in interstitial waters, determines the stability of heavy metals and secondary release in sediments. However, little is known about the composition and metal-binding patterns of DOM in interstitial water from oligotrophic lakes affected by different anthropogenic perturbations. Here, 18 interstitial water samples were prepared from sediments in agricultural, residential, tourist, and forest regions in an oligotrophic lake (Shengzhong Lake in Sichuan Province, China) watershed. Interstitial water quality and DOM composition, properties, and Cu(II)- and Pb(II)-binding characteristics were measured via physicochemical analysis, UV-vis spectroscopic, fluorescence excitation-emission matrix-parallel factor analysis (EEM-PARAFAC), and fluorescence titration methods. The DOM, which was produced mainly by microbial activities, had low molecular weights, humification degrees, and aromaticity. Based on EEM-PARAFAC results, the DOM was generally composed of tryptophan- (57.7%), terrestrial humic- (18.7%), microbial humic- (15.6%), and tyrosine-like (8.0%) substances. The DOM in the metal complexes was primarily composed of tryptophan-like substances, which accounted for ~42.6% of the DOM-Cu(II) complexes and ~72.0% of the DOM-Pb(II) complexes; however, microbial humic-like substances primarily contributed to the stability of DOM-Cu(II) (logKCu = 3.7-4.6) and DOM-Pb(II) (logKPb = 4.3-4.8). Water quality parameters did not significantly affect the stability of DOM-metal complexes. We demonstrated that the metal-binding patterns of DOM in interstitial water from oligotrophic lakes are highly dependent on microbial DOM composition and are affected by anthropogenic perturbations to a lesser extent.
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Affiliation(s)
- Yanmei Liu
- College of Environmental Science and Engineering, China West Normal University, Nanchong, 637009, China
| | - Mengyuan Li
- College of Environmental Science and Engineering, China West Normal University, Nanchong, 637009, China
| | - Dong Ren
- College of Environmental Science and Engineering, China West Normal University, Nanchong, 637009, China
- Nanchong Key Laboratory of Eco-Environmental Protection and Pollution Prevention in Jialing River Basin, Nanchong, 637000, China
| | - Yunxiang Li
- College of Environmental Science and Engineering, China West Normal University, Nanchong, 637009, China.
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5
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Mu L, Dong R, Wang J, Yue J, Pan L, Song C, Wei Z. The positive effect of the enzyme inducer (MnSO 4) on the formation of humic substance in rice straw composting by stimulating key microorganisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 923:171460. [PMID: 38442764 DOI: 10.1016/j.scitotenv.2024.171460] [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: 12/19/2023] [Revised: 03/01/2024] [Accepted: 03/01/2024] [Indexed: 03/07/2024]
Abstract
This study investigated the impact of adding enzyme inducer (MnSO4) on humic substance (HS) formation during straw composting. The results demonstrated that both enzyme inducer treatment group (Mn) and functional microorganism treatment group (F) led to an increase in the content of HS compared to the treatment group without enzyme inducer and functional microorganism (CK). Interestingly, the enzyme inducer exhibited a higher promoting effect on HS (57.80 % ~ 58.58 %) than functional microbial (46.54 %). This was because enzyme inducer stimulated the growth of key microorganisms and changed the interaction relationship between microorganisms. The structural equation model suggested that the enzyme inducer promoted the utilization of amino acids by the fungus and facilitated the conversion of precursors to humic substance components. These findings provided a direction for improving the quality of composting products from agricultural straw waste. It also provided theoretical support for adding MnSO4 to compost.
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Affiliation(s)
- Linying Mu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Runshi Dong
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Jiaqi Wang
- College of Life Science, Northeast Agricultural University, Harbin 150030, China
| | - Jieyu Yue
- College of Life Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Lina Pan
- College of Life Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Caihong Song
- School of Life Science, Liaocheng University, Liaocheng 252000, China
| | - Zimin Wei
- College of Life Science, Northeast Agricultural University, Harbin 150030, China; College of Life Sciences, Tianjin Normal University, Tianjin 300387, China.
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6
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Huang H, Zan S, Shao K, Chen H, Fan J. Spatial distribution characteristics and interaction effects of DOM and microbial communities in kelp cultivation areas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 920:170511. [PMID: 38309352 DOI: 10.1016/j.scitotenv.2024.170511] [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: 08/30/2023] [Revised: 01/17/2024] [Accepted: 01/26/2024] [Indexed: 02/05/2024]
Abstract
The influence of macroalgae cultivation on aquaculture carbon sinks is significant, with microbial carbon (C) pumps contributing to a stable inert dissolved carbon pool in this context. Concurrently, dissolved organic matter (DOM) exchange at the marine sediment-water interface profoundly affects global ecosystem element cycling. However, the interactions between DOM and bacterial communities at the sediment-water interface in kelp cultivation areas, especially regarding microbial function prediction, have not been fully explored. This study analyzed the DOM characteristics, environmental factors, and bacterial community structure in the Tahewan kelp--Saccharina japonica cultivated area and compared them with those in non-cultivated areas. The results indicated significantly higher dissolved organic carbon (DOC) concentrations in the kelp culture area, particularly in surface seawater and overlying water. The dominant bacterial phyla in both regions included Pseudomonadota, Actinomycetota, and Bacteroidota in both regions, while Desulfobacterota was more prevalent in the sediment environment of the cultivated region. Parallel factor analysis (EEM-PARAFAC) was used to identify DOM components, among which component C2 (a microbial humic-like substance DOM) was highly resistant to microbial degradation. We infer that C2 has similar properties to recalcitrant dissolved organic matter (RDOM). Analysis of the predicted functional genes based on 16S rRNA gene data showed that methanol oxidation, methylotrophy, and methanotrophy were significant in the bottom seawater of the cultivation area. The carbon (C), nitrogen (N), and sulfur (S) cycle functional genes in the sediment environment of the kelp cultivation area were more active than those in other areas, especially in which sulfate reduction and denitrification were the two main processes. Furthermore, a DOM priming effect was identified in the cultivated sediment environment, where kelp-released labile dissolved organic matter (LDOM) stimulates rapid degradation of the original RDOM, potentially enhancing C sequestration.
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Affiliation(s)
- Huiling Huang
- College of Oceanography and Ecological Science, Shanghai Ocean University, Shanghai, China; State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, China
| | - Shuaijun Zan
- Groundwater Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Shenzhen International Graduate School, Tsinghua University, Shenzhen, China
| | - Kuishuang Shao
- State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, China
| | - Hanjun Chen
- State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, China; College of Marine Technology and Environment, Dalian Ocean University, Dalian, China
| | - Jingfeng Fan
- College of Oceanography and Ecological Science, Shanghai Ocean University, Shanghai, China; State Environmental Protection Key Laboratory of Coastal Ecosystem, National Marine Environmental Monitoring Center, Dalian, China; College of Marine Technology and Environment, Dalian Ocean University, Dalian, China.
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Wang Y, Su N, Lian E, Wang R. Spatial heterogeneity of sedimentary organic matter sources in the Yangtze River estuary: Implications from fatty acid biomarkers. MARINE POLLUTION BULLETIN 2024; 201:116249. [PMID: 38484535 DOI: 10.1016/j.marpolbul.2024.116249] [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: 11/23/2023] [Revised: 02/26/2024] [Accepted: 03/07/2024] [Indexed: 04/07/2024]
Abstract
This study investigated the sources of sedimentary organic matter (OM) in the Yangtze River estuary (YRE), using multiple biomarkers. The results of stable carbon isotope (δ13C) and total organic carbon to nitrogen ratio (TOC/TN) suggests the contribution of marine-derived OM significantly increased seawards, while fatty acid (FA) composition provides more specific information on OM sources. In total, 30 components of FAs were identified at the studied 17 sites, which mainly composed of phytoplankton FA, followed by ubiquitous FA and bacterial FA, while terrestrial FA contributed less to the total FAs. Under the strong impacts of the large physicochemical gradients in the YRE, TOC, TN and FA components showed higher concentrations in the estuary mixing zone (especially within the turbidity maximum zone), attributing to their strong binding with OM-enriched fine particles. The spatial heterogeneity of sedimentary OM sources was highly impacted by salinity and Chl-a, as well as bacteria-mediated OM degradation.
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Affiliation(s)
- Yunhui Wang
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Ni Su
- State Key Laboratory of Marine Geology, School of Ocean and Earth Science, Tongji University, Shanghai 200092, PR China
| | - Ergang Lian
- State Key Laboratory of Marine Geology, School of Ocean and Earth Science, Tongji University, Shanghai 200092, PR China; Research Center for Monitoring and Environmental Sciences, Taihu Basin & East China Sea Ecological Environment Supervision and Administration Authority, Ministry of Ecology and Environment, Shanghai 200120, PR China
| | - Rui Wang
- Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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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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9
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Zhao B, Yao P, Wei Q, Bianchi TS, Watts EG, Wang B, Yu Z. Effects of seasonal deposition-erosion cycle on sedimentary organic carbon remineralization and oxygen consumption in a large-river delta-front estuary. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170377. [PMID: 38280579 DOI: 10.1016/j.scitotenv.2024.170377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 01/20/2024] [Accepted: 01/21/2024] [Indexed: 01/29/2024]
Abstract
Seasonal sediment deposition-erosion events are dominant drivers of particle-solute dynamics in large-river delta-front estuaries (LDEs), but their influence on elemental cycles is not yet fully understood. To better constrain the role of deposition-erosion events on elemental cycling in LDEs, benthic fluxes of dissolved inorganic carbon (DIC), oxygen, and pore-water solute profiles were measured over different seasons in the Changjiang LDE. Benthic DIC efflux (23.4 ± 6.0 mmol C m-2 d-1) was greater than oxygen influx (7.5 ± 2.0 mmol O2 m-2 d-1) in summer but less in winter (7.7 ± 1.2 mmol C m-2 d-1 and 10.1 ± 1.5 mmol O2 m-2 d-1, respectively). The additional oxygen consumption in sediments in winter was likely due to the oxidation of inorganic diagenetic reductive products (IDRP) (e.g., NH4+, Fe2+, and Mn2+) in deeper sediments exposed by erosion, which resulted in the development of an "oxygen debt". Sedimentary oxygen respiration accounted for at least 48 % of total oxygen consumption (oxygen consumption in both water column and sediment) in winter and was significantly greater than in summer (∼15 %); this highlighted the importance of winter sediment erosion in oxygen depletion. In addition to IDRP oxidation, the remineralization of resuspended sedimentary organic carbon in water column also contributed to the oxygen consumption. The global dataset on benthic DIC and oxygen fluxes provides evidence that the "oxygen debt" is likely to be widespread in LDEs, exerting a significant impact on global carbon and oxygen cycling.
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Affiliation(s)
- Bin Zhao
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China; Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Laoshan Laboratory, Qingdao 266237, China
| | - Peng Yao
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Laoshan Laboratory, Qingdao 266237, China.
| | - Qinsheng Wei
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China; Laboratory for Marine Ecology and Environmental Science, Laoshan Laboratory, Qingdao 266237, China
| | - Thomas S Bianchi
- Department of Geological Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Emily G Watts
- Department of Geological Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Baodong Wang
- Key Laboratory of Marine Eco-Environmental Science and Technology, First Institute of Oceanography, Ministry of Natural Resources, Qingdao 266061, China; Laboratory for Marine Ecology and Environmental Science, Laoshan Laboratory, Qingdao 266237, China
| | - Zhigang Yu
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Laoshan Laboratory, Qingdao 266237, China
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10
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Yu W, Yang H, Chen J, Liao P, Wu J, Jiang L, Guo W. Molecular insights into the microbial degradation of sediment-derived DOM in a macrophyte-dominated lake under aerobic and hypoxic conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 916:170257. [PMID: 38253098 DOI: 10.1016/j.scitotenv.2024.170257] [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: 06/12/2023] [Revised: 12/21/2023] [Accepted: 01/16/2024] [Indexed: 01/24/2024]
Abstract
The mineralization of dissolved organic matter (DOM) in sediments is an important factor leading to the eutrophication of macrophyte-dominated lakes. However, the changes in the molecular characteristics of sediment-derived DOM during microbial degradation in macrophyte-dominated lakes are not well understood. In this study, the microbial degradation process of sediment-derived DOM in Lake Caohai under aerobic and hypoxic conditions was investigated using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and metagenomics. The results revealed that the microbial degradation of sediment-derived DOM in macrophyte-dominated lakes was more intense under aerobic conditions. The microorganisms mainly metabolized the protein-like substances in the macrophyte-dominated lakes, and the carbohydrate-active enzyme genes and protein/lipid-like degradation genes played key roles in sediment-derived DOM degradation. Organic compounds with high H/C ratios such as lipids, carbohydrates, and protein/lipid-like compounds were preferentially removed by microorganisms during microbial degradation. Meanwhile, there was an increase in the abundance of organic molecular formula with a high aromaticity such as tannins and unsaturated hydrocarbons with low molecular weight and low double bond equivalent. In addition, aerobic/hypoxic environments can alter microbial metabolic pathways of sediment-derived DOM by affecting the relative abundance of microbial communities (e.g., Gemmatimonadetes and Acidobacteria) and functional genes (e.g., ABC.PE.P1 and ABC.PE.P) in macrophyte-dominated lakes. The abundances of lipids, unsaturated hydrocarbons, and protein compounds in aerobic environments decreased by 58 %, 50 %, and 44 %, respectively, compared to in hypoxic environments under microbial degradation. The results of this study deepen our understanding of DOM biodegradation in macrophyte-dominated lakes under different redox environments and provide new insights into nutrients releases from sediment and continuing eutrophication in macrophyte-dominated lakes.
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Affiliation(s)
- Wei Yu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China; School of Resources and Environment, Anhui Agricultural University, Hefei 230036, PR China
| | - Haiquan Yang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China.
| | - Jingan Chen
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
| | - Peng Liao
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
| | - Jiaxi Wu
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
| | - Lujia Jiang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China; College of Biological and Environmental Engineering, Guiyang University, Guiyang 550005, PR China
| | - Wen Guo
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, PR China
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11
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Chen ZL, Zhang H, Yi Y, He Y, Li P, Wang Y, Wang K, Yan Z, He C, Shi Q, He D. Dissolved organic matter composition and characteristics during extreme flood events in the Yangtze River Estuary. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 914:169827. [PMID: 38190911 DOI: 10.1016/j.scitotenv.2023.169827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 12/19/2023] [Accepted: 12/30/2023] [Indexed: 01/10/2024]
Abstract
Understanding the molecular composition and fate of dissolved organic matter (DOM) during transport in estuaries is essential for gaining a comprehensive understanding of its role within the global biogeochemical cycle. In 2020, a catastrophic flood occurred in the Yangtze River basin. It is currently unknown whether differences in hydrologic conditions due to extreme flooding will significantly impact the estuarine to oceanic DOM cycle. We determined the DOM composition in the Yangtze River estuary (YRE) to the East China Sea by using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) during the high discharge and the flood period (monthly average discharge was 1.2 times higher) on the same trajectory. Our study found that the composition of DOM is more diverse, and more DOM molecules were introduced to the YRE during the flood, especially in the freshwater end member. The result revealed that the DOM was significantly labile and unstable during the flood period. A total of 1840 unique molecular formulas were identified during the flood period, most of which were CHON, CHONS, and CHOS compounds, most likely resulting from anthropogenic inputs from upstream. Only 194 of these molecules were detected in the seawater end member after transporting to the sea, suggesting that the YRE served as a 'filter' of DOM. However, the flood enhances the transport of a group of terrigenous DOM, that is resistant to photodegradation and biodegradation. As a result, YRE experienced ~1.6 times higher terrigenous DOC flux than high discharge period. Considering the increased frequency of future floods, our study provides a preliminary basis for further research on how floods affect the composition and characteristics of estuarine DOM. With the help of the FT-ICR MS technique, we can now better understand the dynamic of DOM composition and characteristics in large river estuaries.
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Affiliation(s)
- Zhao Liang Chen
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories, 999077, Hong Kong
| | - Haibo Zhang
- National Marine Environmental Monitoring Center, Dalian, Liaoning 116023, China.
| | - Yuanbi Yi
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories, 999077, Hong Kong
| | - Yuhe He
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, 999077, Hong Kong
| | - Penghui Li
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai, Guangdong 519082, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong 519080, China
| | - Yuntao Wang
- State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, Zhejiang 310012, China
| | - Kai Wang
- Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Zhenwei Yan
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories, 999077, Hong Kong
| | - Chen He
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Changping, Beijing 102249, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Changping, Beijing 102249, China
| | - Ding He
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories, 999077, Hong Kong; State Key Laboratory of Marine Pollution, City University of Hong Kong, Tat Chee Avenue, Kowloon, 999077, Hong Kong; State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, Zhejiang 310012, China.
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12
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Ni Z, Wu Y, Ma Y, Li Y, Li D, Lin W, Wang S, Zhou C. Spatial gradients and molecular transformations of DOM, DON and DOS in human-impacted estuarine sediments. ENVIRONMENT INTERNATIONAL 2024; 185:108518. [PMID: 38430584 DOI: 10.1016/j.envint.2024.108518] [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: 09/02/2023] [Revised: 01/11/2024] [Accepted: 02/18/2024] [Indexed: 03/04/2024]
Abstract
Dissolved organic matter (DOM) constitutes the most active fraction in global carbon pools, with estuarine sediments serving as significant repositories, where DOM is susceptible to dynamic transformations. Anthropogenic nitrogen (N) and sulfur (S) inputs further complicate DOM by creating N-bearing DOM (DON) and S-bearing DOM (DOS). This study delves into the spatial gradients and transformation mechanisms of DOM, DON, and DOS in Pearl River Estuary (PRE) sediments, China, using combined techniques of UV-visible spectroscopy, Excitation-emission matrix (EEM) fluorescence spectroscopy, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), and microbial high-throughput sequencing. Results uncovered a distinct spatial gradient in DOM concentration, aromaticity (SUVA254), hydrophobicity (SUVA260), the content of substituent groups including carboxyl, carbonyl, hydroxyl and ester groups (A253/A203) of chromophoric DOM (CDOM), and the abundances of tyrosine/tryptophan-like protein and humic-like substances in fluorophoric DOM (FDOM). These all decreased from upper to lower PRE, accompanied by a decrease in O3S and O5S components, indicating seaward reduction in the contribution of terrestrial OM, especially anthropogenic inputs. Additionally, sediments exhibited a reduction in molecular diversity (number of formulas) of DOM, DON, and DOS from upper to lower PRE, with molecules tending towards a lower nominal oxidation state of carbon (NOSC) and higher bio-reactivity (MLBL), molecular weight (m/z) and saturation (H/C). While molecular composition of DOM remained similar in PRE sediments, the relative abundance of lignin-like substances decreased, with a concurrent increase in protein-like and lipid-like substances in DON and DOS from upper to lower PRE. Mechanistic analysis identified the joint influence of terrestrial OM, anthropogenic N/S inputs, and microbial processes in shaping the spatial gradients of DOM, DON, and DOS in PRE estuarine sediments. This study contributes valuable insights into the intricate spatial gradients and transformations of DOM, DON, and DOS within human-impacted estuarine sediments.
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Affiliation(s)
- Zhaokui Ni
- Guangdong-Hong Kong Joint Laboratory for Water Security, Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China; Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed, Kunming 650034, China
| | - Yue Wu
- National Engineering Laboratory for Lake Pollution Control and Ecological Restoration, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yu Ma
- Guangdong-Hong Kong Joint Laboratory for Water Security, 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
| | - Yu Li
- Guangdong-Hong Kong Joint Laboratory for Water Security, Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China
| | - Dan Li
- College of Urban Construction, Nanjing Tech University, Nanjing 211816, China
| | - Wei Lin
- Guangdong-Hong Kong Joint Laboratory for Water Security, Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China
| | - Shengrui Wang
- Guangdong-Hong Kong Joint Laboratory for Water Security, 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
| | - Chunyang Zhou
- Guangdong-Hong Kong Joint Laboratory for Water Security, Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai 519087, China.
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13
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Chen ZL, Yi Y, Zhang H, Li P, Wang Y, Yan Z, Wang K, He C, Shi Q, He D. Differences in Dissolved Organic Matter Molecular Composition along Two Plume Trajectories from the Yangtze River Estuary to the East China Sea. ACS ENVIRONMENTAL AU 2024; 4:31-41. [PMID: 38250340 PMCID: PMC10797684 DOI: 10.1021/acsenvironau.3c00030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 11/08/2023] [Accepted: 11/14/2023] [Indexed: 01/23/2024]
Abstract
Analyzing the molecular composition change of dissolved organic matter (DOM) during transportation in estuaries can enhance our understanding of the fate of DOM. However, the impact of hydrologic conditions resulting from large river plumes on the DOM cycle are less explored, and previous studies were insufficient to capture the molecular fate that occur during the transportation process. In this study, we used a range of bulk and optical techniques, as well as Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), to determine the concentration and characteristics of DOM along two trajectories of downstream plumes of diluted water of the Yangtze (Changjiang) River estuary (YRE) during the high discharge season. These two plumes situated along the route of the summer Changjiang diluted water (CDW) have been identified and named CDW-North (CDW-N) and CDW-South (CDW-S), respectively. Despite having the same riverine end-member origin, the turbidity zone in YRE significantly modifies the molecular characteristics and composition of DOM. The results of FT-ICR MS indicated a spatial variation of DOM composition in the coastal zone of the two plumes. The relative intensities of the CHO, CHOS, and CHONS compounds are negatively correlated with salinity. In addition, the coastal zones of both CDW-N and CDW-S are characterized by more autochthonous DOM sources. More CHON compounds in CDW-N are probably due to the production of autochthonous DOM in offshore waters. The activity of phytoplankton increased the surface dissolved oxygen level of CDW-N in the coastal zone. However, the hypoxic zone formed at the bottom of the CDW-N due to microbial degradation of organic matter and may further benefit the preservation of CHON compounds. Our study emphasizes that the characteristics and composition of the estuarine DOM can be significantly shaped by distinct large river plumes. Furthermore, using FT-ICR MS in combination with complementary techniques can better assist in identifying the sources and transformation mechanisms of estuarine DOM in large river plume-affected systems and provide more valuable insights into the role of DOM in the estuarine biogeochemical cycle.
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Affiliation(s)
- Zhao Liang Chen
- Department
of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories 999077, Hong Kong, China
| | - Yuanbi Yi
- Department
of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories 999077, Hong Kong, China
| | - Haibo Zhang
- National
Marine Environmental Monitoring Center, Dalian, Liaoning 116023, China
| | - Penghui Li
- School
of Marine Sciences, Sun Yat-Sen University, Zhuhai, Guangdong 519082, China
- Southern
Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, Guangdong 519080, China
| | - Yuntao Wang
- State
Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural
Resources, Hangzhou, Zhejiang 310012, China
| | - Zhenwei Yan
- Department
of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories 999077, Hong Kong, China
| | - Kai Wang
- Department
of Ocean Science and Engineering, Southern
University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Chen He
- State
Key Laboratory of Heavy Oil Processing, China University of Petroleum, Changping, Beijing 102249, China
| | - Quan Shi
- State
Key Laboratory of Heavy Oil Processing, China University of Petroleum, Changping, Beijing 102249, China
| | - Ding He
- Department
of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Clear Water Bay, New Territories 999077, Hong Kong, China
- State
Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural
Resources, Hangzhou, Zhejiang 310012, China
- School
of Earth Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
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14
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Wu K, Cui K, Huang Y, Yu K, Chen X, Li CX, Chen Y. Degree of human activity exert differentiated influence on conventional and emerging pollutants in drinking water source. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:7214-7226. [PMID: 38157162 DOI: 10.1007/s11356-023-31440-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 12/05/2023] [Indexed: 01/03/2024]
Abstract
Anthropogenic pollution poses a significant threat to drinking water sources worldwide. Previous studies have focused on the occurrence of pollutants in drinking water sources, but the impact of human activities on different types of pollutants in drinking water sources is still unclear. In this study, we chose the upper reaches of the Dongjiang River (URDR) as a case study to investigate the distribution characteristics of conventional pollutants, pesticides, and antibiotics along the gradient of human intervention. Our findings reveal that human activities can effect both conventional pollutants and emerging pollutants in the URDR to varying degrees. The escalation of human activities correlates with a rising trend in conventional pollutants, such as nitrogen (N) and phosphorus (P). Notably, only C1 (terrestrial humus) in dissolved organic matter (DOM) exhibits this increasing pattern. Pesticide and antibiotic concentrations are highest in areas with moderate and high levels of human activity, respectively, and the degree of eutrophication of drinking water closely follows the gradient of human activity. Our results also indicate that most pesticides pose a significant risk in the URDR, particularly pyrethroid pesticides (PYRs). Out of all antibiotics, only Norfloxacin (NFX) and Penicillin G (PENG) are classified as high-risk, with NFX exhibiting significant variation across different degrees of human activity. C1 and TP were the most important factors affecting the distribution of organophosphorus (OPPs) and PYRs, respectively. In conclusion, varying degrees of human activity exert differentiated influences on conventional and emerging pollutants in drinking water sources.
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Affiliation(s)
- Ke Wu
- School of Resources and Environmental Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, 230009, China
| | - Kangping Cui
- School of Resources and Environmental Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, 230009, China
| | - Yuansheng Huang
- College of Ecology and Environment, Xinjiang University, Urumqi, 830017, China
| | - Kaifeng Yu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Xing Chen
- Key Lab of Aerospace Structural Parts Forming Technology and Equipment of Anhui Province, Institute of Industry and Equipment Technology, Hefei University of Technology, Hefei, 230009, China
| | - Chen-Xuan Li
- School of Resources and Environmental Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, 230009, China
| | - Yihan Chen
- School of Resources and Environmental Engineering, Hefei University of Technology, 193 Tunxi Road, Hefei, 230009, China.
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15
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Yi Y, Liu T, Merder J, He C, Bao H, Li P, Li S, Shi Q, He D. Unraveling the Linkages between Molecular Abundance and Stable Carbon Isotope Ratio in Dissolved Organic Matter Using Machine Learning. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:17900-17909. [PMID: 37079797 DOI: 10.1021/acs.est.3c00221] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Dissolved organic matter (DOM) is a complex mixture of molecules that constitutes one of the largest reservoirs of organic matter on Earth. While stable carbon isotope values (δ13C) provide valuable insights into DOM transformations from land to ocean, it remains unclear how individual molecules respond to changes in DOM properties such as δ13C. To address this, we employed Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to characterize the molecular composition of DOM in 510 samples from the China Coastal Environments, with 320 samples having δ13C measurements. Utilizing a machine learning model based on 5199 molecular formulas, we predicted δ13C values with a mean absolute error (MAE) of 0.30‰ on the training data set, surpassing traditional linear regression methods (MAE 0.85‰). Our findings suggest that degradation processes, microbial activities, and primary production regulate DOM from rivers to the ocean continuum. Additionally, the machine learning model accurately predicted δ13C values in samples without known δ13C values and in other published data sets, reflecting the δ13C trend along the land to ocean continuum. This study demonstrates the potential of machine learning to capture the complex relationships between DOM composition and bulk parameters, particularly with larger learning data sets and increasing molecular research in the future.
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Affiliation(s)
- Yuanbi Yi
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong SAR, China
| | - Tongcun Liu
- School of Mathematics and Computer Science, Zhejiang A&F University, Hangzhou 311300, China
| | - Julian Merder
- Department of Global Ecology, Carnegie Institution for Science, Stanford, California 94305, United States
| | - Chen He
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
| | - Hongyan Bao
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China
| | - Penghui Li
- School of Marine Sciences, Sun Yat-Sen University, Zhuhai 519082, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519000, China
| | - Siliang Li
- Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin 300072, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
| | - Ding He
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong, Hong Kong SAR, China
- State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, Hong Kong SAR, China
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16
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Dai T, Li Z, Wang L, Li T, Qiu P, Wang J, Song H. Potential Linkage between Heavy Metal Pollution Risk Assessment and Dissolved Organic Matter Spectra in the WWTPs-River Integrated Area-Case Study from Ashi River. TOXICS 2023; 11:904. [PMID: 37999556 PMCID: PMC10674235 DOI: 10.3390/toxics11110904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 10/30/2023] [Accepted: 11/02/2023] [Indexed: 11/25/2023]
Abstract
Direct sewage discharge can cause severe damage to the water environment of the river. However, the impacts of dissolved organic matter (DOM) in the discharge on the original pattern of DOM and the distribution of heavy metals (HMs) in the river are little known. How to monitor such areas in a long-term and systematic manner also needs to be urgently addressed. In this paper, we characterized the DOM of the sediments in the WWTPs (wastewater treatment plants)-river integrated zone by ultraviolet-visible absorption spectroscopy (UV-vis), three-dimensional excitation-emission matrix (3D-EEM) combined with parallel factor (PARAFAC) method. The effects of WWTP on receiving waters were investigated, and the potential link between DOM and HM pollution was explored. Hg (Igeo: 3.94 ± 0.65; EF: 44.83 ± 31.11), Cd (Igeo: 1.81 ± 0.69; EF: 8.02 ± 2.97), Cu (Igeo: 1.61 ± 0.83; EF: 6.85 ± 2.37), Zn (Igeo: 1.55 ± 0.54; EF: 7.24 ± 3.58), and Ni (Igeo: 1.46 ± 0.56; EF: 6.12 ± 1.99) in rivers were the primary risk sources of HM. The combined pollution risk indicates that the WWTPs-river integrated area is in a high pollution risk state. Moreover, α(254) has a significant correlation with pollution indicators and can be used as a proxy indicator. These results help to understand better the impact of WWTPs on receiving water bodies and the potential connection between DOM and HM pollution and provide new ideas for monitoring the water environment in highly polluted areas.
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Affiliation(s)
- Taoyan Dai
- School of Water Resources and Electricity, Heilongjiang University, Harbin 150080, China
| | - Zhijun Li
- School of Water Resources and Electricity, Heilongjiang University, Harbin 150080, China
| | - Liquan Wang
- School of Water Resources and Electricity, Heilongjiang University, Harbin 150080, China
| | - Tienan Li
- Heilongjiang Province Hydraulic Research Institute, Harbin 150080, China
| | - Pengpeng Qiu
- Heilongjiang Province Hydraulic Research Institute, Harbin 150080, China
| | - Jun Wang
- Heilongjiang Province Hydraulic Research Institute, Harbin 150080, China
| | - Haotian Song
- School of Water Resources and Electricity, Heilongjiang University, Harbin 150080, China
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17
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Jiao K, Deng B, Song P, Ding H, Liu H, Lian B. Difference Analysis of the Composition of Iron (Hydr)Oxides and Dissolved Organic Matter in Pit Mud of Different Pit Ages in Luzhou Laojiao and Its Implications for the Ripening Process of Pit Mud. Foods 2023; 12:3962. [PMID: 37959081 PMCID: PMC10648004 DOI: 10.3390/foods12213962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 10/25/2023] [Accepted: 10/26/2023] [Indexed: 11/15/2023] Open
Abstract
Long-term production practice proves that good liquor comes out of the old cellar, and the aged pit mud is very important to the quality of Luzhou-flavor liquor. X-ray diffraction, Fourier transform ion cyclotron resonance mass spectrometry, and infrared spectroscopy were used to investigate the composition characteristics of iron-bearing minerals and dissolved organic matter (DOM) in 2-year, 40-year, and 100-year pit mud and yellow soil (raw materials for making pit mud) of Luzhou Laojiao distillery. The results showed that the contents of total iron and crystalline iron minerals decreased significantly, while the ratio of Fe(II)/Fe(III) and the content of amorphous iron (hydr)oxides increased significantly with increasing cellar age. DOM richness, unsaturation, and aromaticity, as well as lignin/phenolics, polyphenols, and polycyclic aromatics ratios, were enhanced in pit mud. The results of the principal component analysis indicate that changes in the morphology and content of iron-bearing minerals in pit mud were significantly correlated with the changes in DOM molecular components, which is mainly attributed to the different affinities of amorphous iron (hydr)oxides and crystalline iron minerals for the DOM components. The study is important for understanding the evolution pattern of iron-bearing minerals and DOM and their interactions during the aging of pit mud and provides a new way to further understand the influence of aged pit mud on Luzhou-flavor liquor production.
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Affiliation(s)
- Kairui Jiao
- College of Life Sciences, Nanjing Normal University, Nanjing 210023, China; (K.J.); (H.L.)
| | - Bo Deng
- National Engineering Research Center of Solid State Brewing, Luzhou 646000, China; (B.D.); (H.D.)
| | - Ping Song
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing 210023, China;
| | - Hailong Ding
- National Engineering Research Center of Solid State Brewing, Luzhou 646000, China; (B.D.); (H.D.)
| | - Hailong Liu
- College of Life Sciences, Nanjing Normal University, Nanjing 210023, China; (K.J.); (H.L.)
| | - Bin Lian
- College of Marine Science and Engineering, Nanjing Normal University, Nanjing 210023, China
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18
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Yang G, Pan H, Lei H, Tong W, Shi L, Chen H. Dissolved organic matter evolution and straw decomposition rate characterization under different water and fertilizer conditions based on three-dimensional fluorescence spectrum and deep learning. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118537. [PMID: 37406492 DOI: 10.1016/j.jenvman.2023.118537] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 06/25/2023] [Accepted: 06/26/2023] [Indexed: 07/07/2023]
Abstract
Straw returning is a sustainable way to utilize agricultural solid waste resources. However, incomplete decomposition of straw will cause harm to crop growth and soil quality. Currently, there is a lack of technology to timely monitor the rate of straw decomposition. Dissolved organic matter (DOM) is the most active organic matter in soil and straw is mainly immersed in the soil in the form of DOM. In order to formulate reasonable straw returning management measures , a timely monitoring method of straw decomposition rate was developed in the study. Three water treatment (60%-65%, 70%-75% and 80%-85% maximum field capacity) and two fertilizer (organic fertilizer and chemical fertilizer) were set up in the management of straw returning to the field. Litterbag method was used to monitor the weight loss rate of straw decomposition under different water and fertilizer conditions in strawberry growth stage. The changes of DOM components were determined by three-dimensional fluorescence spectroscopy (3D-EEM). From the faster decomposition period to the slower decomposition period, the main components of DOM changed from protein-like components to humus-like components. At the end of the experiment, the relative content of humus-like components under the treatment of organic fertilizer and moderate water was the highest. Convolutional neural network (CNN) combined with 3D-EEM was used to identify the decomposition speed of straw. The classification precision of neural network validation set and test are 85.7% and 81.2%, respectively. In order to predict the decomposition rate of straw under different water and fertilizer conditions, 3D-EEM data of DOM were used as the input of CNN, parallel factor analysis (PARAFAC) and fluorescence region integral (FRI), and dissolved organic carbon data were used as the input of dissolved organic carbon linear prediction. The prediction model based on CNN had the best effect (R2 = 0.987). The results show that this method can effectively identify the spectral characteristics and predict the decomposition rate of straw under different conditions of water and fertilizer, which is helpful to promote the efficient decomposition of straw.
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Affiliation(s)
- Guang Yang
- College of Water Resources, North China University of Water Resources and Electric Power, Zhengzhou, Henan, 450011, PR China
| | - Hongwei Pan
- College of Water Resources, North China University of Water Resources and Electric Power, Zhengzhou, Henan, 450011, PR China.
| | - Hongjun Lei
- College of Water Resources, North China University of Water Resources and Electric Power, Zhengzhou, Henan, 450011, PR China.
| | - Wenbin Tong
- College of Water Resources, North China University of Water Resources and Electric Power, Zhengzhou, Henan, 450011, PR China
| | - Lili Shi
- College of Water Resources, North China University of Water Resources and Electric Power, Zhengzhou, Henan, 450011, PR China
| | - Huiru Chen
- College of Water Resources, North China University of Water Resources and Electric Power, Zhengzhou, Henan, 450011, PR China
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19
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He C, Yi Y, He D, Cai R, Chen C, Shi Q. Molecular composition of dissolved organic matter across diverse ecosystems: Preliminary implications for biogeochemical cycling. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118559. [PMID: 37418915 DOI: 10.1016/j.jenvman.2023.118559] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 05/28/2023] [Accepted: 06/29/2023] [Indexed: 07/09/2023]
Abstract
Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) has been widely applied to characterize the molecular composition of dissolved organic matter (DOM) in different ecosystems. Most previous studies have explored the molecular composition of DOM focused on one or a few ecosystems, which prevents us from tracing the molecular composition of DOM from different sources and further exploring its biogeochemical cycling across ecosystems. In this study, a total of 67 DOM samples, including soil, lake, river, ocean, and groundwater, were analyzed by negative-ion electrospray ionization FT-ICR MS. Results show that molecular composition of DOM varies dramatically among diverse ecosystems. Specifically, the forest soil DOM exhibited the strongest terrestrial signature of molecules, while the seawater DOM showed the most abundant of biologically recalcitrant components, for example, the carboxyl-rich alicyclic molecules were abundant in the deep-sea waters. Terrigenous organic matter is gradually degraded during its transport along the river-estuary-ocean continuum. The saline lake DOM showed similar DOM characteristics with marine DOM, and sequestrated abundant recalcitrant DOM. By comparing these DOM extracts, we found that human activities likely lead to an increase in the content of S and N-containing heteroatoms in DOM, this phenomenon was commonly found in the paddy soil, polluted river, eutrophic lake, and acid mine drainage DOM samples. Overall, this study compared molecular composition of DOM extracted from various ecosystems, providing a preliminary comparison on the DOM fingerprint and an angle of view into biogeochemical cycling across different ecosystems. We thus advocate for the development of a comprehensive molecular fingerprint database of DOM using FT-ICR MS across a wider range of ecosystems. This will enable us to better understand the generalizability of the distinct features among ecosystems.
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Affiliation(s)
- Chen He
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
| | - Yuanbi Yi
- Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China; Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Ding He
- Department of Ocean Science and Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong SAR, China
| | - Ruanhong Cai
- State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Sciences, Xiamen University, Xiamen, 361005, China
| | - Chunmao Chen
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China.
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20
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Li M, Tuo Y, Wu Q, Lin H, Feng Q, Duan Y, Wei J, Chen Z, Lv J, Li L. One-step synthesis of thiol-functionalized metal coordination polymers: effective and superfast removal of Hg (II) in the different matrices to ppb level. CHEMOSPHERE 2023; 338:139618. [PMID: 37487976 DOI: 10.1016/j.chemosphere.2023.139618] [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: 04/12/2023] [Revised: 07/20/2023] [Accepted: 07/21/2023] [Indexed: 07/26/2023]
Abstract
The mercury in water bodies has posed a great threat to the environment and humans, and removing mercury and purifying wastewater has become a global environmental issue. Adopting Zn(II) coordination polymers (Zn-CPs) emerged as a new approach, however, the kind of Zn-CPs, which solely consisted of amino groups, exhibited unsatisfactory performance in capturing Hg(II) at a low level and causing the subsequent leaching of Zn(II) after adsorption. In this study, we fabricated the thiol-modified Zn-based coordination polymers (Zn-CPs-SH) through a one-step solvothermal reaction to efficiently capture Hg(II) from wastewater. Its preeminent adsorption performance could be maintained across a broad range of pH (2-7), ion strength (Cl-, SO42-, and NO3- at 0-10,000 mg/L), and dissolved organic matter (0-100 mg/L). The impressive properties, including fast kinetics (k2∼1.01 × 10-4 L/min), outstanding adsorption capacity (1278.72 mg/g, 298 K), superior selectivity (Kd∼2.3 × 104 mL/g), and excellent regeneration capability (Re = 93.54% after 5 cycles), were attributed to the ultra-abundance of adsorption sites donating from thiol groups, which was revealed by XPS analysis, DFT calculations, and molecular orbital theory. Noteworthy, the high practical application potential of Zn-CPs-SH was demonstrated by its outstanding Hg(II) removal efficiency (Re ≥ 99.10%) in various Hg(II)-spiked water matrices, e.g., tap water, river water, and industrial wastewater. Importantly, the residual Hg(II) in the treated water declined to the ppb level without any Zn(II) leaching. Overall, it is highly anticipated that the incorporation of Zn-CPs-SH would facilitate the practical implementation of highly efficient Hg(II) removal in wastewater treatment owing to its exhibiting high selective affinity, superior adsorption capacity, and enhanced efficiency.
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Affiliation(s)
- Mingzhi Li
- School of Resources, Environment and Materials, Guangxi University, Nanning, China
| | - Yongjie Tuo
- School of Resources, Environment and Materials, Guangxi University, Nanning, China
| | - Qiuxia Wu
- School of Resources, Environment and Materials, Guangxi University, Nanning, China
| | - Haiying Lin
- School of Resources, Environment and Materials, Guangxi University, Nanning, China; State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, Guangxi University, Nanning, China.
| | - Qingge Feng
- School of Resources, Environment and Materials, Guangxi University, Nanning, China; State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, Guangxi University, Nanning, China
| | - Yu Duan
- School of Resources, Environment and Materials, Guangxi University, Nanning, China
| | - Junqi Wei
- School of Resources, Environment and Materials, Guangxi University, Nanning, China
| | - Zixuan Chen
- School of Resources, Environment and Materials, Guangxi University, Nanning, China
| | - Jiatong Lv
- School of Resources, Environment and Materials, Guangxi University, Nanning, China
| | - Lianghong Li
- School of Resources, Environment and Materials, Guangxi University, Nanning, China
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21
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Chen X, Cai R, Zhuo X, Chen Q, He C, Sun J, Zhang Y, Zheng Q, Shi Q, Jiao N. Niche differentiation of microbial community shapes vertical distribution of recalcitrant dissolved organic matter in deep-sea sediments. ENVIRONMENT INTERNATIONAL 2023; 178:108080. [PMID: 37429058 DOI: 10.1016/j.envint.2023.108080] [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: 03/12/2023] [Revised: 06/29/2023] [Accepted: 06/29/2023] [Indexed: 07/12/2023]
Abstract
Sedimentary organic matter provides carbon substrates and energy sources for microorganisms, which drive benthic biogeochemical processes and in turn modify the quantity and quality of dissolved organic matter (DOM). However, the molecular composition and distribution of DOM and its interactions with microbes in deep-sea sediments remain poorly understood. Here, molecular composition of DOM and its relationship with microbes were analyzed in samples collected from two sediment cores (∼40 cm below the sea floor), at depths of 1157 and 2253 m from the South China Sea. Results show that niche differentiation was observed on a fine scale in different sediment layers, with Proteobacteria and Nitrososphaeria dominating the shallow sediments (0-6 cm) and Chloroflexi and Bathyarchaeia prevailing in deeper sediments (6-40 cm), indicating correspondence of microbial community composition with both geographical isolation and the availability of organic matter. An intimate link between the DOM composition and microbial community further indicates that, microbial mineralization of fresh organic matter in the shallow layer potentially resulted in the accumulation of recalcitrant DOM (RDOM), while relatively low abundance of RDOM was linked to anaerobic microbial utilization in deeper sediment layers. In addition, higher RDOM abundance in the overlying water, as compared to that in the surface sediment, suggests that sediment might be a source of deep-sea RDOM. These results emphasize the close relation between the distribution of sediment DOM and different microbial community, laying a foundation for understanding the complex dynamics of RDOM in deep-sea sediment and water column.
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Affiliation(s)
- Xiaoxia Chen
- College of Ocean and Earth Sciences and State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361005, China
| | - Ruanhong Cai
- College of Ocean and Earth Sciences and State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361005, China.
| | - Xiaocun Zhuo
- State Key Laboratory of Heavy Oil Processing, Research Centre for Geomicrobial Resources and Application, China University of Petroleum, Beijing 102249, China
| | - Quanrui Chen
- College of Ocean and Earth Sciences and State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361005, China
| | - Chen He
- State Key Laboratory of Heavy Oil Processing, Research Centre for Geomicrobial Resources and Application, China University of Petroleum, Beijing 102249, China
| | - Jia Sun
- College of Ocean and Earth Sciences and State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361005, China
| | - Yao Zhang
- College of Ocean and Earth Sciences and State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361005, China
| | - Qiang Zheng
- College of Ocean and Earth Sciences and State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361005, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, Research Centre for Geomicrobial Resources and Application, China University of Petroleum, Beijing 102249, China
| | - Nianzhi Jiao
- College of Ocean and Earth Sciences and State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China; Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen 361005, China; Carbon Neutral Innovation Research Center, Xiamen University, Xiamen 361005, China.
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22
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Ma K, Shen H, Zhou T, Xin H, Wu F, Zhang G. Water quality characteristics and evaluation of Qilian Mountain National Park section in Heihe River Basin based on water quality indices and 3D fluorescence technology. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:4373-4387. [PMID: 36795261 DOI: 10.1007/s10653-023-01492-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 01/15/2023] [Indexed: 06/18/2023]
Abstract
The water quality of the Heihe River Basin affects the life quality and health of tens of thousands of residents along it. However, there are relatively few studies that evaluate its water quality. In this study, we used principal component analysis (PCA), an improved comprehensive water quality index (WQI), and three-dimensional (3D) fluorescence technology to identify pollutants and evaluate water quality at nine monitoring sites in the Qilian Mountain National Park in Heihe River Basin. PCA was applied to concentrate the water quality indices into nine items. The analysis shows that the water quality in the study area is mainly polluted by organic matter, nitrogen, and phosphorus. According to the revised WQI model, the water quality of the study area is from moderate to good, while the water quality of Qinghai section is worse than that of Gansu section. According to the 3D fluorescence spectrum analysis of the monitoring sites, the organic pollution of water comes from vegetation decay, animal feces, and some human activities. This study can not only provide support and basis for water environment protection and management in the Heihe River Basin, but also promote the healthy development of the water environment in the Qilian Mountains.
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Affiliation(s)
- Kai Ma
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
- Key Laboratory of Yellow River Environment of Gansu Province, Lanzhou, 730070, People's Republic of China
| | - Huidong Shen
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
- Key Laboratory of Yellow River Environment of Gansu Province, Lanzhou, 730070, People's Republic of China
| | - Tianhong Zhou
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
- Key Laboratory of Yellow River Environment of Gansu Province, Lanzhou, 730070, People's Republic of China
| | - Huijuan Xin
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
- Key Laboratory of Yellow River Environment of Gansu Province, Lanzhou, 730070, People's Republic of China
| | - Fuping Wu
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
- Key Laboratory of Yellow River Environment of Gansu Province, Lanzhou, 730070, People's Republic of China
| | - Guozhen Zhang
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China.
- Key Laboratory of Yellow River Environment of Gansu Province, Lanzhou, 730070, People's Republic of China.
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23
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Maqbool T, Jiang D. Electrokinetic remediation leads to translocation of dissolved organic matter/nutrients and oxidation of aromatics and polysaccharides. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 876:162703. [PMID: 36906032 DOI: 10.1016/j.scitotenv.2023.162703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/03/2023] [Accepted: 03/03/2023] [Indexed: 06/18/2023]
Abstract
Dissolved organic matter (DOM) in the sediment matrix affects contaminant remediation through consumption of oxidants and binding with contaminants. Yet the change in DOM during remediation processes, particularly during electrokinetic remediation (EKR), remains under-investigated. In this work, we elucidated the fate of sediment DOM in EKR using multiple spectroscopic tools under abiotic and biotic conditions. We found that EKR led to significant electromigration of the alkaline-extractable DOM (AEOM) toward the anode, followed by transformation of the aromatics and mineralization of the polysaccharides. The AEOM remaining in the cathode (largely polysaccharides) was resistant to reductive transformation. Limited difference was noted between abiotic and biotic conditions, indicating the dominance of electrochemical processes when relatively high voltages were applied (1-2 V/cm). The water-extractable organic matter (WEOM), in contrast, showed an increase at both electrodes, which was likely attributable to pH-driven dissociations of humic substances and amino acid-type constituents at the cathode and the anode, respectively. Nitrogen migrated with the AEOM toward the anode, but phosphorus remained immobilized. Understanding the redistribution and transformation of DOM could inform studies on contaminant degradation, carbon and nutrient availability, and sediment structural changes in EKR.
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Affiliation(s)
- Tahir Maqbool
- Department of Civil, Construction, and Environmental Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA
| | - Daqian Jiang
- Department of Civil, Construction, and Environmental Engineering, The University of Alabama, Tuscaloosa, AL 35487, USA.
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24
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Wang X, Wu R, He Y. Field evidences of fluorescent dissolved organic matter (FDOM) as potential fingerprints for agricultural and urban sources in river environment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023:10.1007/s11356-023-27352-z. [PMID: 37155107 DOI: 10.1007/s11356-023-27352-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 04/26/2023] [Indexed: 05/10/2023]
Abstract
Field evidences of the fluorescence differences between agricultural and urban river reaches are still lack. In this study, the middle reaches of Danhe River (DH) and Mihe River (MH) in Shouguang, China, were designed as agricultural and urban river reaches, respectively, to compare the the fluorescence differences in disparate river reaches using excitation-emission matrix coupled with parallel factor analysis (EEM-PARAFAC). Three fluorescence components were identified. C1 (Ex/Em=230,255,295 nm/420 nm) was categorized as humic-like fluorophores, C2 (Ex/Em=230,275 nm/330 nm) was recognized as tryptophan-like substances, and C3 (Ex/Em=215 nm/290 nm) was noted as tyrosine-like and phenylalanine-like compounds. The results showed that the FDOM posed significant differences between agricultural and urban river reaches (P < 0.001). The monitoring sites in DH were rich in C2 (1.90 ± 0.62 Raman Unit (RU), mean ± standard deviation), and the monitoring sites in MH were rich in C3 (1.32 ± 0.51 RU). Redundancy analysis revealed that C2 could be regarded as a fluorescence indicator of agricultural sewage in river environment, while C3 was recognized as a fluorescence indicator of domestic sewage in river environment. In conclusion, this study provided field evidences of FDOM as potential fingerprints for agricultural and urban sources in river environment.
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Affiliation(s)
- Xiangyu Wang
- College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Ruilin Wu
- College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
- Department of Ecology and Environment of Shanxi Province, Taiyuan, 030024, Shanxi, China
| | - Yong He
- College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China.
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25
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Bai L, Bai Y, Hou Y, Zhang S, Wang S, Ding A. Ecological water replenishment to the Yongding River, China: effects of different water sources on inorganic ions and organic matter characteristics. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:39107-39120. [PMID: 36595171 DOI: 10.1007/s11356-022-25017-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023]
Abstract
Ecological water replenishment is considered to be an important project to adjust river ecosystems with water shortages and degradation, and its impact on the water quality of the target river section deserves attention. By investigating the characteristics of inorganic ions and organic components of the Beijing section of the Yongding River (YDR) from upstream to downstream, the sources of inorganic ions and dissolved organic matter (DOM) during an ecological water replenishment event were analysed and discussed. This study illustrated the hydrochemical response to different supplemental water sources in three sections of the YDR (mountain gorge section (MGS), urban plain section (UPS), and suburb plain section (SPS)). The results showed that the total dissolved solids (TDS) and ion concentrations were significantly different (p < 0.001) in the three river sections due to different supplemental water sources. The highest concentration of TDS was found in the UPS (870.92 mg/L) replenished by reclaimed water, while the lowest concentration of TDS was found in the SPS (306.95 mg/L) replenished by the water of the South-to-North Water Diversion Project (SNWD). Despite the differences in the water sources of replenishment, the optical parameters of DOM and fluorescent components showed similar protein-like dominated endogenous source characteristics in the three river sections of the YDR, which was due to the influence of reservoir water (MGS and SPS) and reclaimed water (UPS). Our study emphasizes the importance of understanding the impact of different water sources on the water replenishment process, which provides a scientific reference for the management of ecological water replenishment.
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Affiliation(s)
- Ling Bai
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yijuan Bai
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Ying Hou
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Shurong Zhang
- State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China.
| | - Shengrui Wang
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
- Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, Beijing, 100875, China
| | - Aizhong Ding
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
- Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, Beijing, 100875, China
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26
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Liu D, Hao Y, Gao H, Yu H, Li Q. Applying synchronous fluorescence spectra with Gaussian band fitting and two-dimensional correlation to characterize structural composition of DOM from soils in an aquatic-terrestrial ecotone. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160081. [PMID: 36372163 DOI: 10.1016/j.scitotenv.2022.160081] [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: 09/21/2022] [Revised: 10/21/2022] [Accepted: 11/05/2022] [Indexed: 06/16/2023]
Abstract
Dissolved organic matter (DOM), the primary participant of carbon and nitrogen cycle, has a great impact on the behavior and fate of organic pollutants and heavy metals in eutrophic lakes. The dynamic spectral properties of DOM fractions were revealed in an aquatic-terrestrial ecotone under the different types of land use. Composite soil samples of different depths (0-20, 20-40 and 40-60 cm) were collected from four different land uses along a disturbed-impact gradient in Taihu Lake, China, i.e., grassland (GRL), forest land (FOL), paddy field (PAF), and vegetable field (VEF). DOM mainly consisted of tyrosine-like material (TYLF), tryptophan-like material (TRLF), microbial humic-like material (MHLF), fulvic-like material (FLF) and humic-like material (HLF) within all soil profiles, where TRLF was the dominant component (61.30 %) using synchronous fluorescence spectroscopy (SFS) combined with principal component analysis and Gaussian band fitting. Based on two-dimensional correlation spectroscopy with SFS and Fourier transform infrared, the variation order of DOM fractions was FLF → MHLF → HLF → TRLF → TYLF within the GRL soil profile, and MHLF exhibited an oppositive change with aliphatic OH and amide I in protein. The order of DOM fractions was MHLF → FLF → HLF → TYLF → TRLF within the FOL soil profile, and the change trend of MHLF remained oppositive with aliphatic OH and CO in ester. The order of DOM within the PAF soil profile fractions was TRLF → MHLF → HLF → TYLF → FLF, and changing trends of TYLF were oppositive to aliphatic OH, CH bending vibration, CH bending vibration and CO in ester. The order of DOM fractions was HLF → TYLF → TRLF → FLF → MHLF within the VEF soil profile, where the changing trend TYLF remained oppositive to aliphatic OH, CH deformations in lignin and aliphatic group and amide I in protein. This study may provide important support for alleviating lake water eutrophication or pollution.
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Affiliation(s)
- Dongping Liu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; College of Water Sciences, Beijing Normal University, Beijing 100875, China
| | - Yan Hao
- Ningxia Environmental Science Research Institute Co., Ltd, Yinchuan 750002, China
| | - Hongjie Gao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Huibin Yu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Qingqian Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
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27
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Xu L, Hu Q, Liao L, Duan Z, Liu S, Chen L, Zhu Q, Zhong A. Hydrological isolation affected the chemo-diversity of dissolved organic matter in a large river-connected lake (Poyang Lake, China). THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158047. [PMID: 35985600 DOI: 10.1016/j.scitotenv.2022.158047] [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: 06/02/2022] [Revised: 08/09/2022] [Accepted: 08/11/2022] [Indexed: 06/15/2023]
Abstract
The transportation processes during aquatic systems regulate the ultimate chemistry of dissolved organic matter (DOM), and in recent years, climate changes and human activities have altered the hydrological patterns of many rivers and lakes, which generated some severe issues, such as hydrological isolation. However, how hydrological isolation affects variations of DOM chemistry in large lake systems is still poorly understood. Here, optical properties and molecular compositions of DOM samples derived from a large river-connected lake (Poyang Lake, China) and its nearby seasonal sub-lakes (formed by hydrological isolation) were characterized using Fourier transform ion cyclotron resonance mass spectrometry (FT ICR MS) and ultraviolet-visible (UV-Vis) spectroscopy. The results revealed more abundance of organic matter in sub-lakes than that in the main lake according to high dissolved organic carbon (DOC) concentrations and absorption coefficients (a254 and a280). Large proportions of CHOS formulas were identified by FT ICR MS in sub-lakes DOM, which were produced through Kraft reactions (sulfide/bisulfide + lignin CHO → CHOS) in the interface of sediment/water, and greatly contributed to aliphatic compounds. In addition, obvious variations of compounds (such as polyphenols, highly unsaturated and aliphatic compounds) and lability of DOM were observed between sub-lakes and main lakes, which were mainly caused by the different degradation pathways of DOM (photodegradation in sub-lakes while biodegradation in the main lake). Our results demonstrated that hydrological isolation has significant impacts on DOM chemistry, and provides an improved understanding of the DOM biogeochemistry process in Poyang Lake and supports the management of the large lake systems.
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Affiliation(s)
- Lei Xu
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332900, China.
| | - Qian Hu
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332900, China
| | - Libing Liao
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332900, China
| | - Zhongxin Duan
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332900, China
| | - Songping Liu
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332900, China
| | - Ludan Chen
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332900, China
| | - Qiuping Zhu
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332900, China
| | - Aiwen Zhong
- Lushan Botanical Garden, Chinese Academy of Sciences, Jiujiang 332900, China.
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Qu L, He C, Wu Z, Dahlgren RA, Ren M, Li P, Shi Q, Li Y, Chen N, Guo W. Hypolimnetic deoxygenation enhanced production and export of recalcitrant dissolved organic matter in a large stratified reservoir. WATER RESEARCH 2022; 219:118537. [PMID: 35526431 DOI: 10.1016/j.watres.2022.118537] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 04/29/2022] [Accepted: 04/29/2022] [Indexed: 06/14/2023]
Abstract
Global impoundment of river systems represents a major anthropogenic forcing to carbon cycling in reservoirs with seasonal thermal stratification. Currently, a quantitative and mechanistic understanding of how hypolimnetic deoxygenation in stratified reservoirs alters dissolved organic matter (DOM) cycling and lateral transport along the river continuum remains unresolved. Herein, we used optical and high-resolution mass spectrometric analyses to track seasonal and spatial compositional changes of DOM from a large, subtropical impounded river in southeast China. Aliphatic compounds were contributed by algal blooms to epilimnetic DOM during the spring/summer and by baseflow to the overall DOM pool during low-discharge periods. Deoxygenation-driven hypolimnetic mineralization enhanced in situ production of bio-refractory molecules and humic-like fluorescent DOM (FDOMH) by utilizing bio-labile DOM and settling biogenic particles during periods of stratification. Production efficiency of hypolimnetic FDOMH was 159-444% higher than that of the global dark ocean, and was strongly regulated by temperature and possibly substrate supply. The in situ production rate of hypolimnetic FDOMH was four to five orders-of-magnitude higher than the dark ocean, with much faster turnover rates in dark inland waters versus the dark ocean. Collectively, these findings indicate that the hypolimnion is a hotspot for microbial carbon transformations, and hence an important source and pool of refractory DOM in aquatic systems. The lateral FDOMH flux increased 10.8-32.1% due to hypolimnetic reservoir release during periods of stratification, highlighting the importance of incorporating hypolimnetic carbon transformations into models for carbon cycling of inland waters and the land-sea interface.
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Affiliation(s)
- Liyin Qu
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361012, China; Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen 361012, China
| | - Chen He
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Changping District, Beijing 102249, China
| | - Zetao Wu
- Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen 361012, China
| | - Randy A Dahlgren
- Department of Land, Air and Water Resources, University of California, Davis 95616, USA
| | - Mingxing Ren
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361012, China; Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen 361012, China
| | - Penghui Li
- School of Marine Sciences, Sun Yat-sen University, Zhuhai 519082, China
| | - Quan Shi
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Changping District, Beijing 102249, China
| | - Yan Li
- National Observation and Research Station for the Taiwan Strait Marine Ecosystem, Xiamen University, Xiamen 361012, China
| | - Nengwang Chen
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361012, China; Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen 361012, China; National Observation and Research Station for the Taiwan Strait Marine Ecosystem, Xiamen University, Xiamen 361012, China.
| | - Weidong Guo
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361012, China; Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Xiamen University, Xiamen 361012, China; National Observation and Research Station for the Taiwan Strait Marine Ecosystem, Xiamen University, Xiamen 361012, China.
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29
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Review of Effects of Dam Construction on the Ecosystems of River Estuary and Nearby Marine Areas. SUSTAINABILITY 2022. [DOI: 10.3390/su14105974] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Dams have made great contributions to human society, facilitating flood control, power generation, shipping, agriculture, and industry. However, the construction of dams greatly impacts downstream ecological environments and nearby marine areas. The present manuscript presents a comprehensive review of the influence of human activities on the environment, especially the effect of dam construction on the ecosystems of river estuaries and nearby marine areas, so as to provide a scientific basis for ecological environment protection. To summarize these impacts, this review used recent studies to comprehensively analyze how dam construction has affected river hydrology, geomorphology, and downstream ecosystems globally. Effects of dams on ecosystems occur through reduced river flow, reduced sediment flux, altered water temperature, changed estuary delta, altered composition and distribution of nutrients, altered structure and distribution of phytoplankton populations, habitat fragmentation, and blocked migration routes in river sections and adjacent seas. Effects of dam construction (especially the Three Gorges Dam) on the Yangtze River were also reviewed. Performing community and mitigation planning before dam construction, exploring new reservoir management strategies (including targeted control of dam storage and flushing sediment operations), banning fishing activities, and removing unnecessary dams (obsolete or small dams) are becoming crucial tools for ecosystem restoration.
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