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  1. Article: Multiple biomarkers for indicating changes of the organic matter source over the last decades in the Min-Zhe sediment zone, the East China Sea

    Li, Yan / Lin, Jia / Xu, Xiang-Po / Liu, Jin-Zhong / Zhou, Qian-Zhi / Wang, Jiang-Hai

    Ecological indicators. 2022 June, v. 139

    2022  

    Abstract: The temporal variation of sedimentary organic matters (SOM) in the East China Sea (ECS) is not fully assessed due to the complicated natural and anthropogenic processes. In this study, the compositions and distributions of multi-biomarker indicators (n- ... ...

    Abstract The temporal variation of sedimentary organic matters (SOM) in the East China Sea (ECS) is not fully assessed due to the complicated natural and anthropogenic processes. In this study, the compositions and distributions of multi-biomarker indicators (n-alkanes, n-alkanols and specific sterols) in a long sediment core collected from the Min-Zhe fined-grained sediment zone of the ECS were systematically studied to reveal variations of SOM sources and phytoplankton records over the last decades. The results of n-alkanes and sterols have demonstrated that terrestrial plants are the dominant SOM source, with the mean proportion of 67%. The temporal variation of terrestrial to marine biomarker ratios (TMBR) agree well with that of the dominant n-alkanes and terrigenous/aquatic ratios (TAR), suggesting that the multi-biomarker indicators yield a better assessment of the SOM source input. The regular variations of terrestrial OM and phytoplankton signals during the past decades record the interaction among marine ecological effects, anthropogenic activities and natural processes (i.e., extreme climate events). As a whole, the elevated productivity of marine phytoplankton since 1952 (mainly caused by enhanced nutrient inputs owing to the intensified human activities) and the decline in the period of 2005–2011 (likely influenced by the water impoundment of the Three Gorges Dam in 2003) were well reconstructed on the basis of brassicasterol (B) and dinosterol (D) indicators in this study. The B/(B + D) ratios also reveal the changes of community structure as a result of variations in the nutrient structure controlled by anthropogenic forcing. Notably, the anomalous peak in the abundance of n-alkanes with the even carbon predominance in about 1990 is identified for the first time, which may occur at that time of the first heavy rainfall after a long drought and is probably of the origin of biomass/fossil fuel combustion.
    Keywords alkanes ; biomarkers ; biomass ; carbon ; climate ; community structure ; drought ; fossil fuels ; fuel combustion ; humans ; organic matter ; phytoplankton ; rain ; sediments ; sterols ; temporal variation ; East China Sea
    Language English
    Dates of publication 2022-06
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 2036774-0
    ISSN 1872-7034 ; 1470-160X
    ISSN (online) 1872-7034
    ISSN 1470-160X
    DOI 10.1016/j.ecolind.2022.108917
    Database NAL-Catalogue (AGRICOLA)

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  2. Article ; Online: The majority of microorganisms in gas hydrate-bearing subseafloor sediments ferment macromolecules.

    Zhang, Chuwen / Fang, Yun-Xin / Yin, Xiuran / Lai, Hongfei / Kuang, Zenggui / Zhang, Tianxueyu / Xu, Xiang-Po / Wegener, Gunter / Wang, Jiang-Hai / Dong, Xiyang

    Microbiome

    2023  Volume 11, Issue 1, Page(s) 37

    Abstract: Background: Gas hydrate-bearing subseafloor sediments harbor a large number of microorganisms. Within these sediments, organic matter and upward-migrating methane are important carbon and energy sources fueling a light-independent biosphere. However, ... ...

    Abstract Background: Gas hydrate-bearing subseafloor sediments harbor a large number of microorganisms. Within these sediments, organic matter and upward-migrating methane are important carbon and energy sources fueling a light-independent biosphere. However, the type of metabolism that dominates the deep subseafloor of the gas hydrate zone is poorly constrained. Here we studied the microbial communities in gas hydrate-rich sediments up to 49 m below the seafloor recovered by drilling in the South China Sea. We focused on distinct geochemical conditions and performed metagenomic and metatranscriptomic analyses to characterize microbial communities and their role in carbon mineralization.
    Results: Comparative microbial community analysis revealed that samples above and in sulfate-methane interface (SMI) zones were clearly distinguished from those below the SMI. Chloroflexota were most abundant above the SMI, whereas Caldatribacteriota dominated below the SMI. Verrucomicrobiota, Bathyarchaeia, and Hadarchaeota were similarly present in both types of sediment. The genomic inventory and transcriptional activity suggest an important role in the fermentation of macromolecules. In contrast, sulfate reducers and methanogens that catalyze the consumption or production of commonly observed chemical compounds in sediments are rare. Methanotrophs and alkanotrophs that anaerobically grow on alkanes were also identified to be at low abundances. The ANME-1 group actively thrived in or slightly below the current SMI. Members from Heimdallarchaeia were found to encode the potential for anaerobic oxidation of short-chain hydrocarbons.
    Conclusions: These findings indicate that the fermentation of macromolecules is the predominant energy source for microorganisms in deep subseafloor sediments that are experiencing upward methane fluxes. Video Abstract.
    MeSH term(s) Methane ; Alkanes ; Carbon ; China ; Chloroflexi
    Chemical Substances Methane (OP0UW79H66) ; Alkanes ; Carbon (7440-44-0)
    Language English
    Publishing date 2023-03-02
    Publishing country England
    Document type Video-Audio Media ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2697425-3
    ISSN 2049-2618 ; 2049-2618
    ISSN (online) 2049-2618
    ISSN 2049-2618
    DOI 10.1186/s40168-023-01482-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Source Indication and Geochemical Significance of Sedimentary Organic Matters from the Xisha Area, the South China Sea.

    Li, Yan / Zhou, Qian-Zhi / Xu, Xiang-Po / Fang, Yun-Xin / Liu, Jin-Zhong / Wang, Jiang-Hai

    Molecules (Basel, Switzerland)

    2021  Volume 26, Issue 22

    Abstract: Although various geochemical and geophysical investigations have already indicated a great resource potential in the Xisha area of the South China Sea, the origin of organic matter and molecular evidence for tracing the migration of hydrocarbons from ... ...

    Abstract Although various geochemical and geophysical investigations have already indicated a great resource potential in the Xisha area of the South China Sea, the origin of organic matter and molecular evidence for tracing the migration of hydrocarbons from deep petroleum reservoirs are still lacking. In this study, systematic organic geochemical analyses, including bulk organic matter parameters and lipid biomarkers were performed for deep sediments from two cores. The C/N ratios and δ
    Language English
    Publishing date 2021-11-11
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules26226808
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Multidecadal records of microplastic accumulation in the coastal sediments of the East China Sea

    Lin, Jia / Xu, Xiao-Ming / Yue, Bei-Ying / Xu, Xiang-Po / Liu, Jin-Zhong / Zhu, Qing / Wang, Jiang-Hai

    Chemosphere. 2021 May, v. 270

    2021  

    Abstract: Microplastics are an emerging hazard in the marine environment, and considered to eventually sink into sediments. An investigation into the long-term variation of microplastic accumulation in sediment cores is essential for understanding the historical ... ...

    Abstract Microplastics are an emerging hazard in the marine environment, and considered to eventually sink into sediments. An investigation into the long-term variation of microplastic accumulation in sediment cores is essential for understanding the historical trend of this contamination and its response to human activities. In this study, the multidecadal changes of microplastic abundances in two sediment cores from the inner shelf of the East China Sea (ECS) were revealed by two methods, i.e., a visual enumeration method based on scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and a quantitative method based on microplastic-derived carbon (MPC) abundances. The features of microplastics were determined via SEM-EDS and micro-Fourier transform infrared spectroscopy (μ-FTIR). The results reveal a multidecadal increasing trend of microplastic accumulation in the coastal sediments of the ECS since the 1960s, which may be jointly governed by the release of plastic wastes and oceanographic dynamics. Meanwhile, the breakpoint of the exponential growth of microplastics in the ECS occurs in 2000 AD, which well matches the rapid increasing of plastic production and consumption in China. Further, based on the MPC contents in sediments, the influence of microplastics on the quantitative evaluation of carbon storage in the ECS has been examined for the first time, revealing an insignificant (<2% before 2014 AD) but potentially-increasing (6.8% by 2025 AD) contribution of microplastics to carbon burial. Our results may provide the important data for evaluating and mitigating the impact of microplastics on the marine environment.
    Keywords X-radiation ; carbon ; carbon sequestration ; humans ; infrared spectroscopy ; marine environment ; microplastics ; quantitative analysis ; China ; East China Sea
    Language English
    Dates of publication 2021-05
    Publishing place Elsevier Ltd
    Document type Article
    Note NAL-light
    ZDB-ID 120089-6
    ISSN 1879-1298 ; 0045-6535 ; 0366-7111
    ISSN (online) 1879-1298
    ISSN 0045-6535 ; 0366-7111
    DOI 10.1016/j.chemosphere.2020.128658
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: Multidecadal records of microplastic accumulation in the coastal sediments of the East China Sea.

    Lin, Jia / Xu, Xiao-Ming / Yue, Bei-Ying / Xu, Xiang-Po / Liu, Jin-Zhong / Zhu, Qing / Wang, Jiang-Hai

    Chemosphere

    2020  Volume 270, Page(s) 128658

    Abstract: Microplastics are an emerging hazard in the marine environment, and considered to eventually sink into sediments. An investigation into the long-term variation of microplastic accumulation in sediment cores is essential for understanding the historical ... ...

    Abstract Microplastics are an emerging hazard in the marine environment, and considered to eventually sink into sediments. An investigation into the long-term variation of microplastic accumulation in sediment cores is essential for understanding the historical trend of this contamination and its response to human activities. In this study, the multidecadal changes of microplastic abundances in two sediment cores from the inner shelf of the East China Sea (ECS) were revealed by two methods, i.e., a visual enumeration method based on scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and a quantitative method based on microplastic-derived carbon (MPC) abundances. The features of microplastics were determined via SEM-EDS and micro-Fourier transform infrared spectroscopy (μ-FTIR). The results reveal a multidecadal increasing trend of microplastic accumulation in the coastal sediments of the ECS since the 1960s, which may be jointly governed by the release of plastic wastes and oceanographic dynamics. Meanwhile, the breakpoint of the exponential growth of microplastics in the ECS occurs in 2000 AD, which well matches the rapid increasing of plastic production and consumption in China. Further, based on the MPC contents in sediments, the influence of microplastics on the quantitative evaluation of carbon storage in the ECS has been examined for the first time, revealing an insignificant (<2% before 2014 AD) but potentially-increasing (6.8% by 2025 AD) contribution of microplastics to carbon burial. Our results may provide the important data for evaluating and mitigating the impact of microplastics on the marine environment.
    MeSH term(s) China ; Environmental Monitoring ; Geologic Sediments ; Humans ; Microplastics ; Plastics ; Water Pollutants, Chemical/analysis
    Chemical Substances Microplastics ; Plastics ; Water Pollutants, Chemical
    Language English
    Publishing date 2020-10-17
    Publishing country England
    Document type Journal Article
    ZDB-ID 120089-6
    ISSN 1879-1298 ; 0045-6535 ; 0366-7111
    ISSN (online) 1879-1298
    ISSN 0045-6535 ; 0366-7111
    DOI 10.1016/j.chemosphere.2020.128658
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: A novel thermoanalytical method for quantifying microplastics in marine sediments.

    Lin, Jia / Xu, Xiang-Po / Yue, Bei-Ying / Li, Yan / Zhou, Qian-Zhi / Xu, Xiao-Ming / Liu, Jin-Zhong / Wang, Qin-Qing / Wang, Jiang-Hai

    The Science of the total environment

    2020  Volume 760, Page(s) 144316

    Abstract: Microplastic pollution in marine environments is of particular concern on its risk to the ecosystem. To assess and manage microplastic contaminants, their quantitative detection in environmental samples is a high priority. However, uncertainties of ... ...

    Abstract Microplastic pollution in marine environments is of particular concern on its risk to the ecosystem. To assess and manage microplastic contaminants, their quantitative detection in environmental samples is a high priority. However, uncertainties of current methods still exist when estimating their abundances, particularly with fine-grained (<1 mm) microplastics. This work reports a novel thermoanalytical method for quantifying microplastics by measuring the contents of microplastic-derived carbon (MPC) in samples under the premise of nearly eliminating the limit of their particle appearances. After validating the method via samples with the spiked microplastics, we have conducted a case study on sediment core H43 that spanned 1925-2009 CE from the Yellow Sea for further illustrating the high reliability and practicability of this method for quantifying microplastics in natural samples. Our results have demonstrated that the proposed method may be a promising technique to determine the mass-related concentrations of the total microplastics in marine sediments for evaluating their pollution status and quantitative contribution to marine carbon storage.
    Language English
    Publishing date 2020-12-09
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 121506-1
    ISSN 1879-1026 ; 0048-9697
    ISSN (online) 1879-1026
    ISSN 0048-9697
    DOI 10.1016/j.scitotenv.2020.144316
    Database MEDical Literature Analysis and Retrieval System OnLINE

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