243 results on '"School of Geographic and Oceanographic Sciences"'
Search Results
2. Dating of the stepped quaternary fluvial terrace system of the Yellow River by electron spin resonance (ESR)
- Author
-
Christophe Falguères, Jean-Jacques Bahain, Chun-Ru Liu, Fei Han, Gongming Yin, Xuefeng Sun, Pierre Voinchet, Muséum national d'Histoire naturelle (MNHN), Chinese Academy of Sciences [Beijing] (CAS), Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), State Key Laboratory of Earthquake Dynamics, China Earthquake Administration (CEA), School of Geographic and Oceanographic Sciences, and Nanjing University (NJU)
- Subjects
010506 paleontology ,Middle Pleistocene ,Floodplain ,Pleistocene ,[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory ,Stratigraphy ,Geochemistry ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,Fluvial ,Yellow River ,010502 geochemistry & geophysics ,01 natural sciences ,Tectonic uplift ,Earth and Planetary Sciences (miscellaneous) ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences ,ESR dating ,geography ,geography.geographical_feature_category ,Geology ,Quartz ,Terrace (geology) ,Fluvial terrace ,Fluvial terrace system ,Alluvium ,Quaternary - Abstract
International audience; Since the 1980's, the improvement of the electron spin resonance (ESR) geochronological method and its application to the dating of bleached quartz extracted from sediments currently permit to provide geochronological data on Pleistocene fluvial deposits. In the present study, we have applied this method on sediments carried out from the Yellow River terrace system in the sector of Zhongwei (Ningxia province, China). This alluvial system is composed of a set of stepped fluvial deposit remnants (T1 to T9) from the actual floodplain (T1) up to 160m of relative height. The ESR ages obtained in this work, by placing the installation of the river terrace system in the Middle and Upper Pleistocene (between 712 and 60ka), give information in relation to the causes of the succession of terraces. The results show that the construction of the system seems not only linked to a continuous regional tectonic uplift in the Middle Pleistocene but that the succession of incisions also seems controlled by Quaternary climatic cycles.
- Published
- 2019
- Full Text
- View/download PDF
3. Deciphering centurial anthropogenic pollution processes in large lakes dominated by socio-economic impacts
- Author
-
Enfeng Liu, Qi Lin, Ji Shen, Pierre Sabatier, Ke Zhang, Fabien Arnaud, State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, People's Republic of China, Environnements, Dynamiques et Territoires de la Montagne (EDYTEM), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), School of Geographic and Oceanographic Sciences, and Nanjing University (NJU)
- Subjects
Pollution ,010504 meteorology & atmospheric sciences ,[SDE.MCG]Environmental Sciences/Global Changes ,media_common.quotation_subject ,010501 environmental sciences ,01 natural sciences ,Freshwater ecosystem ,[SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry ,Environmental protection ,Earth and Planetary Sciences (miscellaneous) ,14. Life underwater ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,Environmental quality ,0105 earth and related environmental sciences ,media_common ,Pollutant ,Driving factors ,Global and Planetary Change ,Ecology ,15. Life on land ,6. Clean water ,Watershed management ,13. Climate action ,Sustainable management ,[SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy ,Environmental science ,Surface runoff - Abstract
Human activities have greatly increased the influx of pollutants into global freshwater ecosystems. Understanding the pollution patterns at multi-decadal scales, and how the socio-economic development and public policy have shaped them, are crucial to assess the current status of environmental quality and develop sound strategies for watershed management. This study takes the test case of large Taihu Lake (∼2,338 km2) in rapidly developing regions of China, to examine the temporal-spatial patterns and driving factors of centurial trace metal and metalloid contamination. Using comparative sedimentary records, we applied multiple geochemical indices and positive matrix factorization modelling to identify the anthropogenic versus natural sources and their contributions. Results identified cadmium, antimony and lead as typical pollutants, with high anthropogenic contribution rates of 58–79 %, 54–62 % and 28–36 %, respectively. Contamination histories were asynchronous across the lake, starting from the 1940s (North) to mid-1990s (East), following the gradient of socio-economic stressors of the sub-basins. Specifically, industrial and agricultural inputs through runoff and river networks were main sources of metal in the northern and western lake parts, accounting for ≥ 70 % since the 1980s. In contrast, aquaculture and agriculture related sources (≥ 80 %) dominated in Eastern Taihu Lake over the last decade. Moreover, atmospheric metal deposition from nearby industrial cities significantly affected the northern parts of the lake. The stationary and/or slightly decreased contamination trends, especially after 2000 AD, shed light into the effectiveness of recent environmental regulation. Our findings suggest, however, that agricultural non-point sources and legacy effects probably delayed reductions in the input of pollutants. Sustainable management of similar large watersheds worldwide, therefore, would benefit by highlighting the role of multiple anthropogenic sources, legacy contamination and lake-specific response.
- Published
- 2020
- Full Text
- View/download PDF
4. Rapid transition from continental breakup to igneous oceanic crust in the South China Sea
- Author
-
Xiao-Long Huang, R. Xiang, Weiping Ding, A.J. Gewecke, Benjamin G. Johnson, Liyan Tian, Sara Satolli, Michael Nirrengarten, Z. Sun, R. Yadav, Hong Jin, Lachit S. Ningthoujam, Kan-Hsi Hsiung, H.C. Larsen, Michael J. Dorais, Eric C. Ferré, Ning Zhao, Z. Jian, David W. Peate, A. Luna, Shijun Jiang, Liang Yi, Yang Zhang, L. Li, C.M. Robinson, Robert Kurzawski, Jessica L. Hinojosa, Deniz Cukur, Stephen A. Bowden, Julie Schindlbeck, P. S. Yu, N. Osono, T. W. Höfig, Adam Klaus, Chih-Chieh Su, L. Zhong, C. Lupi, Jacopo Boaga, S.M. Skinner, Kelsie Dadd, A. Furusawa, Jian Lin, Zhifei Liu, Carlos A. Alvarez-Zarikian, H. Wu, Patricia Persaud, Yifeng Chen, Enqing Huang, Chunji Liu, Y. Li, G. Zhong, N. Qiu, Susanne M. Straub, J. Zhang, Shiming Wan, Chao Lei, Fabricio Ferreira, B. Li, C. Zhang, Isabel Sauermilch, Joann M. Stock, Geoffroy Mohn, Anne Briais, X. Su, Anders McCarthy, Baoqi Huang, F.M. van der Zwan, Dynamique de la lithosphère et des bassins sédimentaires (IPGS) (IPGS-Dylbas), Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Géosciences et Environnement Cergy (GEC), Fédération INSTITUT DES MATÉRIAUX DE CERGY-PONTOISE (I-MAT), Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine, Department of Mathematics and Statistics, University of Maryland [Baltimore County] (UMBC), University of Maryland System-University of Maryland System, Nanjing Electronic Devices Institute, C Electronic Devices Institute, Texas A&M University [College Station], Dynamique terrestre et planétaire (DTP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), inconnu, Inconnu, Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS), Universidad de Talca, Department of Electrical Engineering, University of Nebraska–Lincoln, University of Nebraska System-University of Nebraska System, Montpellier Research in Management (MRM), Université Paul-Valéry - Montpellier 3 (UPVM)-Université de Perpignan Via Domitia (UPVD)-Groupe Sup de Co Montpellier (GSCM) - Montpellier Business School-Université de Montpellier (UM), School of Geographic and Oceanographic Sciences, Nanjing University (NJU), Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences [Beijing] (CAS), Laboratoire du Futur (LOF), Université Sciences et Technologies - Bordeaux 1 (UB)-RHODIA-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche en Energie Electrique de Nantes Atlantique EA4642 (IREENA), Institut Universitaire de Technologie Saint-Nazaire (IUT Saint-Nazaire), Université de Nantes (UN)-Université de Nantes (UN)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Institut Universitaire de Technologie - La Roche-sur-Yon (IUT La Roche-sur-Yon), Université de Nantes (UN)-Université de Nantes (UN), Imperial College London, Key Laboratory of Marine Geology and Environment [China, Institute of Oceanology [China], Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin [Austin], Hunan Research Academy of Environmental Sciences, Paul Scherrer Institute (PSI), Systèmes de Référence Temps Espace (SYRTE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), AIR (AIR), Institut de recherches sur la catalyse et l'environnement de Lyon (IRCELYON), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Université Paul Cézanne - Aix-Marseille 3-Centre National de la Recherche Scientifique (CNRS)-Avignon Université (AU)-Université de Provence - Aix-Marseille 1, University of Nebraska [Lincoln], Université Montpellier 1 (UM1)-Groupe Sup de Co Montpellier (GSCM) - Montpellier Business School-Université Paul-Valéry - Montpellier 3 (UPVM)-Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Perpignan Via Domitia (UPVD), Université Sciences et Technologies - Bordeaux 1-RHODIA-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche en Electrotechnique et Electronique de Nantes Atlantique EA4642 (IREENA), and Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)
- Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,Rift ,010504 meteorology & atmospheric sciences ,International Ocean Discovery Program ,010502 geochemistry & geophysics ,01 natural sciences ,Mantle (geology) ,Paleontology ,Igneous rock ,13. Climate action ,Oceanic crust ,Passive margin ,Lithosphere ,Magmatism ,General Earth and Planetary Sciences ,14. Life underwater ,Earth and Planetary Sciences (all) ,Geology ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences - Abstract
Continental breakup represents the successful process of rifting and thinning of the continental lithosphere, leading to plate rupture and initiation of oceanic crust formation. Magmatism during breakup seems to follow a path of either excessive, transient magmatism (magma-rich margins) or of igneous starvation (magma-poor margins). The latter type is characterized by extreme continental lithospheric extension and mantle exhumation prior to igneous oceanic crust formation. Discovery of magma-poor margins has raised fundamental questions about the onset of ocean-floor type magmatism, and has guided interpretation of seismic data across many rifted margins, including the highly extended northern South China Sea margin. Here we report International Ocean Discovery Program drilling data from the northern South China Sea margin, testing the magma-poor margin model outside the North Atlantic. Contrary to expectations, results show initiation of Mid-Ocean Ridge basalt type magmatism during breakup, with a narrow and rapid transition into igneous oceanic crust. Coring and seismic data suggest that fast lithospheric extension without mantle exhumation generated a margin structure between the two endmembers. Asthenospheric upwelling yielding Mid-Ocean Ridge basalt-type magmatism from normal-temperature mantle during final breakup is interpreted to reflect rapid rifting within thin pre-rift lithosphere.
- Published
- 2018
- Full Text
- View/download PDF
5. Experimental Study on insulation properties of C4F7N/N2 mixture substituting SF6 in insulation
- Author
-
Tian, Shuang, Cressault, Yann, Zhang, X., Xiao, S., Li, Y., Zhang, J., Chen, Q., LAboratoire PLasma et Conversion d'Energie (LAPLACE), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT), Matériaux et Procédés Plasmas (LAPLACE-MPP), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), School of Mechanical and Manufacturing Engineering, The University of Sydney, School of Geographic and Oceanographic Sciences, Nanjing University (NJU), Laboratoire de Mécanique Multiphysique Multiéchelle (LaMcube), and Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SPI.PLASMA]Engineering Sciences [physics]/Plasmas - Abstract
International audience
- Published
- 2018
6. Coupled ESR and U-series dating of Middle Pleistocene hominin site Bailongdong cave, China
- Author
-
Xuefeng Sun, Fei Han, Gongming Yin, Qingfeng Shao, Jean-Jacques Bahain, State Key Laboratory of Earthquake Dynamics, China Earthquake Administration (CEA), College of Geographical Sciences, Nanjing Normal University (NNU), Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), School of Geographic and Oceanographic Sciences, Nanjing University (NJU), Chinese Academy of Sciences [Beijing] (CAS), and Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
010506 paleontology ,geography ,Series (stratigraphy) ,geography.geographical_feature_category ,Pleistocene ,[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory ,Stratigraphy ,chemistry.chemical_element ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,Geology ,Uranium ,010502 geochemistry & geophysics ,01 natural sciences ,Paleontology ,Cave ,chemistry ,Human evolution ,Stage (stratigraphy) ,Earth and Planetary Sciences (miscellaneous) ,Sedimentary rock ,Cosmogenic nuclide ,ComputingMilieux_MISCELLANEOUS ,0105 earth and related environmental sciences - Abstract
The fossil evidence of hominins in China is crucial to understand the human evolution and dispersal in Eurasia. However, the dating of Chinese Early and Middle Pleistocene hominin record remains a serious problem. In this study, we applied coupled ESR/U-series dating method on Bailongdong hominin cave site in Hubei Province, central China, which is a key area to study early human migration between South and North China. The U-series analyses show that the fossil teeth samples from three horizons are close or beyond equilibrium, which indicate very early uptake or potential loss of uranium. Single saturation exponential fitting of 10 dose points irradiated up to 4 kGy was used for DE determination except one by double saturation exponential fitting with 16 dose points up to 63 kGy. Calculated by two uranium migration models, we obtain a weighted mean age of 509 ± 16 ka for five fossil teeth from layer 2. Combined with cosmogenic nuclides 26Al/10Be burial dating carried out on the cave deposits beneath the fossil layers in previous study, the multi-methods dating study places Bailongdong site at the early stage of Middle Pleistocene, and pinpoints the deposition of the fossil remains to the time of marine isotope stages 13. This is in agreement with the fauna composition and sedimentary characteristics which show a subtropical-tropical warm forest-grass environment. The multi-methods dating of Bailongdong site by both cosmogenic and coupled ESR/U-series methods is a good example for the future chronological studies of early human sites in China.
- Published
- 2017
- Full Text
- View/download PDF
7. Contribution des méthodes ESR et ESR/U-Th à la datation de quelques gisements pléistocènes de Chine
- Author
-
P. Voinchet, Xuefeng Sun, Gongming Yin, Fei Han, Qingfeng Shao, Chun-Ru Liu, Christophe Falguères, Jean-Jacques Bahain, Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), College of Geographical Sciences, Nanjing Normal University (NNU), State Key Laboratory of Earthquake Dynamics, China Earthquake Administration (CEA), School of Geographic and Oceanographic Sciences, and Nanjing University (NJU)
- Subjects
010506 paleontology ,History and Philosophy of Science ,[SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory ,Anthropology ,media_common.quotation_subject ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,Art ,010502 geochemistry & geophysics ,01 natural sciences ,Humanities ,0105 earth and related environmental sciences ,media_common - Abstract
International audience; Depuis le début des années 2000, des travaux portant sur la chronologie des premiers peuplements humains de Chine par les méthodes de la résonance de spin électronique (ESR) sur quartz sédimentaires et de la résonance de spin électronique couplée à l’uranium-thorium (ESR/U-Th) sur dents ont été menés en collaboration par des équipes françaises et chinoises sur quelques sites archéologiques ou géologiques chinois : Yunxian, Dali, Tangshan, Zongwei, Nihewan, Longgupo et plusieurs sites à giganthopithèques du Guangxi. Après une présentation rapide des méthodes de datation utilisées, quelques-uns des résultats majeurs obtenus dans le cadre de cette collaboration sont succinctement présentés et discutés.
- Published
- 2017
- Full Text
- View/download PDF
8. A 108.83-m ice-core record of atmospheric dust deposition at Mt. Qomolangma (Everest), Central Himalaya
- Author
-
Shugui Hou, Jiawen Ren, Dahe Qin, Barbara Delmonte, Shichang Kang, Jérôme Chappellaz, Paul Andrew Mayewski, J. R. Petit, Susan Kaspari, Sungmin Hong, Jianzhong Xu, State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Changchun Branch] (CAS), School of Geographic and Oceanographic Sciences, Nanjing University (NJU), Climate Change Institute [Orono] (CCI), University of Maine, CLIPS, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), State Key Laboratory of Cryospheric Science, Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Chinese Academy of Sciences (Grant No. KZCX3-SW-344 and 100 Talents Project) the Natural Science Foundation of China (Grant No 40825017), Chinese Academy of Sciences [Changchun Branch] (CAS)-Cold and Arid Regions Environmental and Engineering Research Institute, Climate Change Institute (CCI), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Xu, J, Hou, S, Qin, D, Kaspari, S, Mayewski, P, Petit, J, Delmonte, B, Kang, S, Ren, J, Chappellaz, J, and Hong, S
- Subjects
010506 paleontology ,China ,Khumbu Himal ,Asia ,010504 meteorology & atmospheric sciences ,Far East ,GEO/04 - GEOGRAFIA FISICA E GEOMORFOLOGIA ,Himalaya ,Ice core ,Climate change ,01 natural sciences ,Quaternary ,Arts and Humanities (miscellaneous) ,paleoclimate ,East Asian Monsoon ,Rongbuk Glacier ,Precipitation ,ice cores, dust, Everest, atmospheric circulation ,[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology ,Holocene ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Mount Everest ,geography ,geography.geographical_feature_category ,Himalayas ,atmospheric deposition ,Qomolangma (Everest) ,Westerlies ,Glacier ,Dust ,Snow ,climate variation ,air temperature ,13. Climate action ,Climatology ,General Earth and Planetary Sciences ,Eurasia ,Xizang ,Physical geography ,Geology - Abstract
The central Himalaya can be regarded as an ideal site for developing a long-term ice core dust record to reflect the environmental signals from regional to semi-hemispheric scales. Here we present a dust record from segments of a 108.83-m ice core recovered from the East Rongbuk (ER) Glacier (27°59′N, 86°55′E; 6518 m a.s.l.) on the northeast slope of Mt. Qomolangma (Everest) in the central Himalaya, covering the period AD 600-1960. Due to rapidly layer thinning and coarse sampling, we primarily discuss the changes in the dust record since AD 1500 in this paper. Results show a significant positive relationship between the dust concentration and reconstructed air temperatures during this period, suggesting a likely cold-humid and warm-dry climatic pattern in the dust source regions, namely Central Asia. This is associated with the variability in the strength of the westerlies and its corresponding precipitation. © 2009 University of Washington.
- Published
- 2010
- Full Text
- View/download PDF
9. An 800-Year Record of Atmospheric As, Mo, Sn, and Sb in Central Asia in High-Altitude Ice Cores from Mt. Qomolangma (Everest), Himalayas
- Author
-
Sungmin Hong, Carlo Barbante, Shugui Hou, Claude F. Boutron, Jiawen Ren, Khanghyun Lee, Soon Do Hur, Kevin J. R. Rosman, Laurie J. Burn, Korea Polar Research Institute (KOPRI), University of Science § Technology, University of Science § Technology, Korea, State Key Laboratory of Cryospheric Sciences, Chinese Academy of Sciences [Changchun Branch] (CAS)-Cold and Arid Regions Environmental and Engineering Research Institute, School of Geographic and Oceanographic Sciences, Nanjing University (NJU), State Key Laboratory of Cryospheric Science, Cold and Arid Regions Environmental and Engineering Research Institute, Department of Imaging and Applied Physics, Curtin University [Perth], Planning and Transport Research Centre (PATREC)-Planning and Transport Research Centre (PATREC), Institute for the Dynamics of Environmental Processes-CNR, University of Ca’ Foscari [Venice, Italy], Environmental Sciences Department, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Supported in Korea by a research grant (PP09010). In China, grants 2007CB411501, 40825017, and SKLCS-ZZ-2008-06 supported this research. In Italy, it was supported within the framework of Projects on 'Environmental Contamination' and 'Glaciology and Paleoclimatology' of the Italian Programma Nazionale di Ricerche in Antartide., Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Changchun Branch] (CAS), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Pollution ,Antimony ,Asia ,Time Factors ,010504 meteorology & atmospheric sciences ,Meteorology ,media_common.quotation_subject ,Central asia ,010501 environmental sciences ,Mineral dust ,Atmospheric sciences ,01 natural sciences ,Arsenic ,Motion ,Ice core ,Environmental Chemistry ,Humans ,[SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology ,Ecosystem ,0105 earth and related environmental sciences ,media_common ,Molybdenum ,Air Pollutants ,Atmosphere ,Altitude ,Ice ,History, 19th Century ,General Chemistry ,Effects of high altitude on humans ,13. Climate action ,Tin ,Period (geology) ,Environmental science ,Inductively coupled plasma ,Deposition (chemistry) - Abstract
International audience; As, Mo, Sn, and Sb have been determined by inductively coupled plasma sector field mass spectrometry (ICP-SFMS) in 143 depth intervals of high-altitude ice cores from Mt. Everest, covering an 800-year time period from 1205 to 2002 AD. The results clearly demonstrate the long-term historical record of atmospheric transport and deposition of As, Mo, Sn, and Sb that has prevailed at high altitudes in the central Himalayas. Natural contributions, mainly from mineral dust, have dominated the atmospheric cycles of As, Mo, Sn, and to some extent Sb during the 700 years prior to the 20th century. Compared to those of the pre-1900 period, pronounced increases of both concentrations and crustal enrichment factors are observed since the 1970s, with the highest increase factor for Sn and the lowest for As. Such increases are attributed to anthropogenic emissions of these elements, largely from stationary fossil fuel combustion and nonferrous metals production, particularly in India. Our central Himalayan ice core record provides an explicit recognition of rising atmospheric As, Mo, Sn, and Sb pollution in response to rapid economic growth in central Asia.
- Published
- 2009
- Full Text
- View/download PDF
10. Sediment dynamic responses of coastal salt marsh to wind waves and swells in a semi-open tidal flat.
- Author
-
Chen S, Gu W, Shi B, Chen Y, Chatzipavlis A, Ding J, Zhang W, Chen Q, and Wang YP
- Abstract
Coastal salt marshes provide effective protection to the coastal environments they front against coastal erosion by reducing the incoming wave energy. Understanding sediment dynamic processes in coastal salt marshes environments is of crucial importance for coastal defense. The objective of this study is to assess the impact of Spartina alterniflora (S. alterniflora) marshes on wave attenuation, sediment transport, and morphodynamics through extensive field records on the Cixi tidal flat in Hangzhou Bay. Results demonstrate that wave attenuation by S. alterniflora marshes increases proportionally with the intensification of wind waves at a consistent water depth or significant wave height. Moreover, wave attenuation in the context of wind waves surpasses that of swells. On average, the wave attenuation provided by S. alterniflora marshes during both wind waves and swells is more than six times greater than that offered by the adjacent mudflat. Additionally, net sediment fluxes within S. alterniflora marshes decrease by 37 % in the presence of swells and 84 % with wind waves, in comparison to the mudflat. The influence of S. alterniflora marshes on tidal flat accretion is more pronounced with wind waves than swells. Notably, observed from summer to winter, the surface accretion of tidal flats is highest (∼26 cm) at the edge of S. alterniflora marshes. This study contributes valuable insights into the complex interactions between salt marshes and hydrodynamic forces, essential for informing coastal management strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
11. Provenance and sedimentation of Pu and 237 Np in the northern Taiwan Strait suffering intensive land-ocean interaction.
- Author
-
Wu M, Shi Y, Liu Z, Pan S, Hou S, Gao J, Zhang S, and Guo H
- Abstract
The China Sea is faced with a heightened risk of anthropogenic radionuclide contamination, whose provenance, scavenging and migration are imperative to investigate to provide the background and nuclear safety emergency assessment. This study pioneers the measurement of anthropogenic plutonium and neptunium (
239+240 Pu and237 Np) concentrations and atom ratios (240 Pu/239 Pu and237 Np/239 Pu) in sediment cores from the northern Taiwan Strait and the adjacent East China Sea using SF-ICP-MS, exploring their applications and characteristics. Typical vertical profiles confirm that Pu and237 Np serve as geochronological tools, with the240 Pu/239 Pu atom ratio as a fingerprint refining the chronology. Fallout history and sedimentary environments have been reconstructed by the comprehensive application of239+240 Pu,237 Np and210 Pb chronologies. The primary sources of Pu isotopes and237 Np are global fallout and close-in fallout from the Pacific Proving Grounds (PPG). Inventories of239+240 Pu ranged from 44 ± 3 Bq/m2 to 348 ± 11 Bq/m2 , with PPG contributions from 57% to 72%, while237 Np inventories varied from 58 ± 5 mBq/m2 to 137 ± 8 mBq/m2 . Differences in the distribution of Pu and237 Np are attributed to their distinct behaviors and sedimentary environments. Particle-reactive Pu isotopes are predominantly preserved in sediment, whereas conservative237 Np remains mostly dissolved in water, easily re-entering seawater from sediment through resuspension processes. Higher environmental mobility also makes more downward diffusion of237 Np than Pu isotopes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
12. Classification and regression tree (CART) for predicting cadmium (Cd) uptake by rice (Oryza sativa L.) and its application to derive soil Cd threshold based on field data.
- Author
-
Tian H, Zhang Y, Yang X, Zhang H, Wang D, Wu P, Yin A, and Gao C
- Subjects
- China, Linear Models, Mining, Oryza, Cadmium analysis, Soil Pollutants analysis, Soil chemistry, Environmental Monitoring methods
- Abstract
The entry of Cd into soil-rice systems is a growing concern as it can pose potential risks to public health. To derive regional soil Cd threshold, a total of 333 paired soil and rice samples was collected in Anhui Province, Eastern China. The results showed that the total soil Cd and soil Zn/Cd were the most significant variables contributing to Cd content in polished rice. The Chinese Soil Quality Standards might overestimate risk posed by Cd-contaminated soil for rice production in the mining area due to high Zn/Cd values of some mining-associated soils. Cd levels in polished rice can be predictable using stepwise multiple linear regression (MLR) model. However, the derived soil Cd threshold based on the MLR model would be unrealistically high. The classification and regression tree method (CART) performed well in simulating Cd levels in polished rice and can be used to derive soil Cd threshold instead of MLR to minimize the uncertainty., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
13. Fungal community determines soil multifunctionality during vegetation restoration in metallic tailing reservoir.
- Author
-
Jin J, Zhao D, Wang J, Wang Y, Zhu H, Wu Y, Fang L, and Bing H
- Subjects
- China, Metals, Heavy, Soil Pollutants metabolism, Soil chemistry, Environmental Restoration and Remediation, Soil Microbiology, Fungi metabolism, Bacteria metabolism
- Abstract
Microorganisms are pivotal in sustaining soil functions, yet the specific contributions of bacterial and fungal succession on the functions during vegetation restoration in metallic tailing reservoirs remains elusive. Here, we explored bacterial and fungal succession and their impacts on soil multifunctionality along a ∼50-year vegetation restoration chronosequence in China's largest vanadium titano-magnetite tailing reservoir. We found a significant increase in soil multifunctionality, an index comprising factors pertinent to soil fertility and microbially mediated nutrient cycling, along the chronosequence. Despite increasing heavy metal levels, both bacterial and fungal communities exhibited significant increase in richness and network complexity over time. However, fungi demonstrated a slower succession rate and more consistent composition than bacteria, indicating their relatively higher resilience to environmental changes. Soil multifunctionality was intimately linked to bacterial and fungal richness or complexity. Nevertheless, when scrutinizing both richness and complexity concurrently, the correlations disappeared for bacteria but remained robust for fungi. This persistence reveals the critical role of the fungal community resilience in sustaining soil multifunctionality, particularly through their stable interactions with powerful core taxa. Our findings highlight the importance of fungal succession in enhancing soil multifunctionality during vegetation restoration in metallic tailing reservoirs, and manipulating fungal community may expedite ecological recovery of areas polluted with heavy metals., Competing Interests: Declaration of Competing Interest The authors declare that they do not have any competing interests that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
14. Change in water column total chlorophyll-a in the Mediterranean revealed by satellite observation.
- Author
-
Li X, Zheng H, Mao Z, Du P, and Zhang W
- Subjects
- Mediterranean Sea, Chlorophyll analysis, Satellite Imagery, Seawater chemistry, Seasons, Mediterranean Region, Machine Learning, Environmental Monitoring methods, Chlorophyll A analysis, Phytoplankton
- Abstract
Chlorophyll-a (Chl-a) is a crucial pigment in algae and macrophytes, which makes the concentration of total Chl-a in the water column (total Chl-a) an essential indicator for estimating the primary productivity and carbon cycle of the ocean. Integrating the Chl-a concentration at different depths (Chl-a profile) is an important way to obtain the total Chl-a. However, due to limited cost and technology, it is difficult to measure Chl-a profiles directly in a spatially continuous and high-resolution way. In this study, we proposed an integrated strategy model that combines three different machine learning methods (PSO-BP, random forest and gradient boosting) to predict the Chl-a profile in the Mediterranean by using several sea surface variables (photosynthetically active radiation, spectral irradiance, sea surface temperature, wind speed, euphotic depth and KD490) and subsurface variables (mixed layer depth) observed by or estimated from satellite and BGC-Argo float observations. After accuracy estimation, the integrated model was utilized to generate the time series total Chl-a in the Mediterranean from 2003 to 2021. By analysing the time series results, it was found that seasonal fluctuation contributed the most to the variation in total Chl-a. In addition, there was an overall decreasing trend in the Mediterranean phytoplankton biomass, with the total Chl- decreasing at a rate of 0.048 mg/m
2 per year, which was inferred to be related to global warming and precipitation reduction based on comprehensive analysis with sea surface temperature and precipitation data., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)- Published
- 2024
- Full Text
- View/download PDF
15. Vertical distribution and influencing factors of soil PAHs under different ecosystem habitats in the Liaohe River Estuary Wetlands, Northeastern China.
- Author
-
Ying Z, Chen S, Zhang C, Liao Q, Yuan F, Feng D, Wang S, Liu Q, and Hao Z
- Subjects
- China, Soil Pollutants analysis, Rivers chemistry, Water Pollutants, Chemical analysis, Polycyclic Aromatic Hydrocarbons analysis, Wetlands, Environmental Monitoring, Estuaries, Soil chemistry, Ecosystem
- Abstract
The vertical distribution, sources and influencing factors of polycyclic aromatic hydrocarbons (PAHs) in soil across ecosystem habitats were investigated around the Liaohe River Estuary (LRE) Wetland. The concentration of Ʃ
16 PAHs ranged from 41.0 to 435.4 ng g-1 dw, with a predominance of low molecular weight PAHs. Overall, PAHs and physicochemical properties of soil decreased with depth. Vegetation was found to increase soil PAHs. Additionally, soil physicochemical properties also regulated PAHs concentration, particularly for PAHs with high molecular weight. Among the habitats, total organic carbon was the key influencing factor for Suaeda heteroptera, while specific surface area was crucial for Phragmites australis. Results of characteristic ratio method and principal component analysis revealed that PAHs in LRE primarily originate petroleum, coal and biomass combustion. In summary, vegetation colonization significantly affected the distribution, sources, and controlling factors of PAHs. These findings are meaningful for management of soil PAHs across various ecosystem habitats., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2025
- Full Text
- View/download PDF
16. Insight into the bacterial community composition of the plastisphere in diverse environments of a coastal salt marsh.
- Author
-
Yuan F, Zou X, Liao Q, Wang T, Zhang H, Xue Y, Chen H, Ding Y, Lu M, Song Y, and Fu G
- Subjects
- China, Microplastics, Geologic Sediments microbiology, Geologic Sediments chemistry, Water Pollutants, Chemical analysis, Environmental Monitoring, Wetlands, Bacteria classification, Bacteria isolation & purification, Microbiota
- Abstract
The microbial community colonized on microplastics (MPs), known as the 'plastisphere', has attracted extensive concern owing to its environmental implications. Coastal salt marshes, which are crucial ecological assets, are considered sinks for MPs. Despite their strong spatial heterogeneity, there is limited information on plastisphere across diverse environments in coastal salt marshes. Herein, a 1-year field experiment was conducted at three sites in the Yancheng salt marsh in China. This included two sites in the intertidal zone, bare flat (BF) and Spartina alterniflora vegetation area (SA), and one site in the supratidal zone, Phragmites australis vegetation area (PA). Petroleum-based MPs (polyethylene and expanded polystyrene) and bio-based MPs (polylactic acid and polybutylene succinate) were employed. The results revealed significant differences in bacterial community composition between the plastisphere and sediment at all three sites examined, and the species enriched in the plastisphere exhibited location-specific characteristics. Overall, the largest difference was observed at the SA site, whereas the smallest difference was observed at the BF site. Furthermore, the MP polymer types influenced the composition of the bacterial communities in the plastisphere, also exhibiting location-specific characteristics, with the most pronounced impact observed at the PA site and the least at the BF site. The polybutylene succinate plastisphere bacterial communities at the SA and PA sites were quite different from the plastispheres from the other three MP polymer types. Co-occurrence network analyses suggested that the bacterial community network in the BF plastisphere exhibited the highest complexity, whereas the network in the SA plastisphere showed relatively sparse interactions. Null model analyses underscored the predominant role of deterministic processes in shaping the assembly of plastisphere bacterial communities across all three sites, with a more pronounced influence observed in the intertidal zone than in the supratidal zone. This study enriches our understanding of the plastisphere in coastal salt marshes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
17. Evaluating the relative influence of climate and human activities on recent vegetation dynamics in West Bengal, India.
- Author
-
Banerjee A, Kang S, Meadows ME, Sajjad W, Bahadur A, Ul Moazzam MF, Xia Z, Mango J, Das B, and Kirsten KL
- Subjects
- India, Human Activities, Humans, Rain, Temperature, Environmental Monitoring, Climate Change
- Abstract
Assessing the relative importance of climate change and human activities is important in developing sustainable management policies for regional land use. In this study, multiple remote sensing datasets, i.e. CHIRPS (Climate Hazard Group InfraRed Precipitation with Station Data) precipitation, MODIS Land Surface Temperature (LST), Enhanced Vegetation Index (EVI), Potential Evapotranspiration (PET), Soil Moisture (SM), WorldPop, and nighttime light have been analyzed to investigate the effect that climate change (CC) and regional human activities (HA) have on vegetation dynamics in eastern India for the period 2000 to 2022. The relative influence of climate and anthropogenic factors is evaluated on the basis of non-parametric statistics i.e., Mann-Kendall and Sen's slope estimator. Significant spatial and elevation-dependent variations in precipitation and LST are evident. Areas at higher elevations exhibit increased mean annual temperatures (0.22 °C/year, p < 0.05) and reduced winter precipitation over the last two decades, while the northern and southwest parts of West Bengal witnessed increased mean annual precipitation (17.3 mm/year, p < 0.05) and a slight cooling trend. Temperature and precipitation trends are shown to collectively impact EVI distribution. While there is a negative spatial correlation between LST and EVI, the relationship between precipitation and EVI is positive and stronger (R
2 = 0.83, p < 0.05). Associated hydroclimatic parameters are potent drivers of EVI, whereby PET in the southwestern regions leads to markedly lower SM. The relative importance of CC and HA on EVI also varies spatially. Near the major conurbation of Kolkata, and confirmed by nighttime light and population density data, changes in vegetation cover are very clearly dominated by HA (87%). In contrast, CC emerges as the dominant driver of EVI (70-85%) in the higher elevation northern regions of the state but also in the southeast. Our findings inform policy regarding the future sustainability of vulnerable socio-hydroclimatic systems across the entire state., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
18. Hidden delta degradation due to fluvial sediment decline and intensified marine storms.
- Author
-
Zhu Q, Xing F, Wang YP, Syvitski J, Overeem I, Guo J, Li Y, Tang J, Yu Q, Gao J, and Gao S
- Abstract
Deltas are threatened by erosion due to climate change and reduced sediment supply, but their response to these changes remains poorly quantified. We investigate the abandoned Yellow River delta that has transitioned from rapid growth to ongoing deterioration due to a river avulsion removing the sediment supply. Integrating bathymetric data, process observations, and sediment transport modeling, we find that while the subaerial delta was stabilized by engineering measures, the subaqueous delta continued to erode due to intensified storms, losing 39% of its mass deposited before the avulsion. Long-term observations show that winter storms initiate scouring of the subaqueous delta, contributing up to 70% of seabed erosion. We then analyze 108 global deltas to assess subaqueous delta erosion risks and identify 17 deltas facing similar situations of sediment decline and storm intensification during the past 40 years. Our findings suggest that subaqueous delta erosion must be integrated into delta sustainability evaluations.
- Published
- 2024
- Full Text
- View/download PDF
19. Spatiotemporal assessment of groundwater quality and quantity using geostatistical and ensemble artificial intelligence tools.
- Author
-
Nourani V, Ghaffari A, Behfar N, Foroumandi E, Zeinali A, Ke CQ, and Sankaran A
- Subjects
- Neural Networks, Computer, Spatial Analysis, Iran, Environmental Monitoring methods, Artificial Intelligence, Groundwater
- Abstract
The study investigated the spatiotemporal relationship between surface hydrological variables and groundwater quality/quantity using geostatistical and AI tools. AI models were developed to estimate groundwater quality from ground-based measurements and remote sensing images, reducing reliance on laboratory testing. Different Kriging techniques were employed to map ground-based measurements and fill data gaps. The methodology was applied to analyze the Maragheh aquifer in northwest Iran, revealing declining groundwater quality due to industrial. discharges and over-extraction. Spatiotemporal analysis indicated a relationship between groundwater depth/quality, precipitation, and temperature. The Root Mean Square Scaled Error (RMSSE) values for all variables ranged from 0.8508 to 1.1688, indicating acceptable performance of the semivariogram models in predicting the variables. Three AI models, namely Feed-Forward Neural Networks (FFNNs), Support Vector Regression (SVR), and Adaptive Neural Fuzzy Inference System (ANFIS), predicted groundwater quality for wet (June) and dry (October) months using input variables such as groundwater depth, temperature, precipitation, Normalized Difference Vegetation Index (NDVI), and Digital Elevation Model (DEM), with Groundwater Quality Index (GWQI) as the target variable. Ensemble methods were employed to combine the outputs of these models, enhancing performance. Results showed strong predictive capabilities, with coefficient of determination values of 0.88 and 0.84 for wet and dry seasons. Ensemble models improved performance by up to 6% and 12% for wet and dry seasons, respectively, potentially advancing groundwater quality modeling in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
20. Sedimentary record of microplastics in coastal wetland, eastern China.
- Author
-
Zhou Y, Zhou S, Chen SS, Li Y, Chen L, Zhang Q, Su B, and Wang T
- Subjects
- Humans, Plastics, Wetlands, Environmental Monitoring, China, Microplastics, Water Pollutants, Chemical analysis
- Abstract
Microplastic (MP) dynamics can reflect history of plastic production and waste management in nearby areas. However, the stratigraphy of MPs in coastal wetlands and their link to policy and economic pattern changes are currently unclear. Here, MP stratigraphic records in sediment core from coastal wetlands in Yancheng, China, were used to reconstruct plastic pollution history. Neural network models simulated how policy intervention and economic development affected MP accumulation over time. We showed that MP abundance curves with boundaries from 1920 to 2019 had four stages. MP growth slowed or even decreased in the mid-to-late 1980s due to improved waste management and wastewater treatment since the late 1980s. Human activities were the primary factor affecting MP abundance and shape, followed by sediment properties. We predict that the environmental impact of MPs will continue to increase in the next decade. Current plastic policy measures focus on predictable waste emissions, but hidden sources like clothing fibers and tire wear that significantly contribute to MP pollution require further attention., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
21. Human-influenced changes in pollution status and potential risk of sediment heavy metals in Xincun Bay, a typical lagoon of Hainan, China.
- Author
-
Hao Z, Qian J, Zheng F, Lin B, Xu M, Feng W, and Zou X
- Subjects
- Humans, Bays, Cadmium analysis, Geologic Sediments chemistry, Environmental Monitoring, Risk Assessment, China, Water Pollutants, Chemical analysis, Metals, Heavy analysis
- Abstract
Pollution status and ecological risks associated with sediment heavy metals (Cu, Pb, Zn, Cd, and Cr) were investigated around Xincun Bay, assessing their spatial variations and relationship with sediment physiochemical factors. Higher concentrations and associated risks were observed in the central region, where mariculture activities were concentrated, compared to non-maricultured areas. Despite with overall low concentrations, Cd had a higher ecological risk. Correlation and principal component analyses revealed similar sources for all metals in Xincun Bay. Heavy metal concentrations varied with expansion of mariculture operations in terms of quantity and scale, confirming the influence of mariculture activities. Sediments around mariculture had higher contents of clay, silt, and total organic carbon (TOC), and finer particle sizes. Quantitative analyses through correlation and linear regression indicated that TOC significantly regulated heavy metal concentration and distribution (p < 0.05). Considering its significant association with TOC, the influence of mean grain size should not be overlooked., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)
- Published
- 2024
- Full Text
- View/download PDF
22. Unraveling the impact of lanthanum on methane consuming microbial communities in rice field soils.
- Author
-
Liu R, Wei Z, Dong W, Wang R, Adams JM, Yang L, and Krause SMB
- Abstract
The discovery of the lanthanide requiring enzymes in microbes was a significant scientific discovery that opened a whole new avenue of biotechnological research of this important group of metals. However, the ecological impact of lanthanides on microbial communities utilizing methane (CH
4 ) remains largely unexplored. In this study, a laboratory microcosm model experiment was performed using rice field soils with different pH origins (5.76, 7.2, and 8.36) and different concentrations of La3+ in the form of lanthanum chloride (LaCl3 ). Results clearly showed that CH4 consumption was inhibited by the addition of La3+ but that the response depended on the soil origin and pH. 16S rRNA gene sequencing revealed the genus Methylobacter, Methylosarcina , and Methylocystis as key players in CH4 consumption under La3+ addition. We suggest that the soil microbiome involved in CH4 consumption can generally tolerate addition of high concentrations of La3+ , and adjustments in community composition ensured ecosystem functionality over time. As La3+ concentrations increase, the way that the soil microbiome reacts may not only differ within the same environment but also vary when comparing different environments, underscoring the need for further research into this subject., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Liu, Wei, Dong, Wang, Adams, Yang and Krause.)- Published
- 2024
- Full Text
- View/download PDF
23. Biodiversity loss through cropland displacement for urban expansion in China.
- Author
-
Li F, Wu S, Liu H, and Yan D
- Subjects
- China, Food Supply, Crops, Agricultural, Conservation of Natural Resources methods, Biodiversity
- Abstract
As a result of rapid economic development, urban expansion reduced the cropland in China. To secure the food supply, cropland displacement to maintain the quantity and quality of cropland has been implemented. Here, we quantified the biodiversity losses due to cropland displacement resulting from urban expansion from a telecoupling perspective in China from 1980 to 2020. A comprehensive multimodel assessment demonstrated that the indirect biodiversity losses due to cropland displacement resulting from urban expansion were approximately 2 to 3 times higher than its direct biodiversity losses, at a total loss of approximately 0.6 % to 1.0 %, as indicated by three biodiversity indicators. Displaced cropland with a higher biodiversity cost but lower cropland productivity is the main reason for the excessive indirect losses and suggests that socioecological processes may be detrimental to the synergistic benefits of the UN Sustainable Development Goal (SDG) for food security and terrestrial biodiversity. This study also identified source-sink hotspots for indirect biodiversity losses, which can contribute to improving biodiversity conservation, optimizing the spatial distribution of cropland and thus enhancing socioecological system sustainability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)
- Published
- 2024
- Full Text
- View/download PDF
24. Trends in the occurrence and accumulation of microplastics in urban soil of Nanjing and their policy implications.
- Author
-
Zhou Y, Wang T, Zou M, Yin Q, Jia Z, Su B, Zhang Q, Chen L, and Zhou S
- Abstract
Urban soil is an important sink of terrestrial microplastics (MPs), and understanding their distribution over time is essential for effective pollution management. Here, based on soil MP data from Nanjing, a typical megacity in eastern China, this study analyzed MP accumulation trends using decision tree and time series network based on soil attributes, POI (point of interest), and human activity factors such as urban industrial structure, transportation, water use. We also evaluated the impact of plastic policy interventions. In the past 15 years, MPs in urban soil in Nanjing have gradually increased, and highly polluted areas have also grown. From 2010 to 2020, the concentration of MPs in urban soil increased from 326.7 items/kg to 480.9 items/kg, with high pollution areas expanding from only 2.0 km
2 (0.7 %) to 48.7 km2 (14.9 %). The accumulation of MPs was also influenced by changing factors due to urbanization. In the early 21st century, residential areas had the largest effect, while in the later period, public passenger transport and domestic water consumption were the dominant factors. The scenarios simulation suggests recent plastic intervention policies have helped alleviate this rate of increase, but MP source management (e.g., laundry fibers, tire wear) still needs improvement. By the proposed method, the past trend of microplastics in urban soil and their relationship with soil properties and human activities can be accurately revealed, which will be helpful for the formulation of countermeasures to mitigate regional soil MP pollution., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
25. Microplastics in agricultural soils on the coastal plain: Spatial characteristics, influencing factors and sources.
- Author
-
Zhou Y, Jia Z, Zheng G, Chen L, Zhang Q, Su B, and Zhou S
- Abstract
Farmland is a major sink for microplastics (MPs), but research on MPs in coastal plain soil, particularly their occurrence in agricultural areas with changing coastlines, is limited. Here, we investigated the distribution, influencing factors and sources of MPs in a typical agricultural county near the southeast coast of China considering different human activities and soil property changes. The average MP concentration in farmland soils was 314 items/kg, ranging from 70.2 to 851.3 items/kg. MPs increased first and then decreased from inland to the coast, and this trend was greatly affected by coastline expansion. Bulk density, clay and textile points of interest (POIs) are the major factors affecting MPs in farmland. Network analysis was used to divide the whole MP community into two modules, and the average similarity between each MP community and the other 25.5 MP communities was >0.5. Overall, the similarity of the MP community tended to decrease with increasing geographical distance (P < 0.01). In the soil environmental factors group, bulk density and clay affected the total MP abundance, accounting for 14.7 % and 9.4 % of MPs, respectively. After fitting 8 types of POIs and the total MP diversity integrated index (MDII) of farmland, washing POIs (R
2 = 0.65, P < 0.01) displayed the greatest and most significant fit with MDII, followed by clothing POIs (R2 = 0.29, P < 0.01). The MDII-POI results showed that the major POI sources of soil MPs were clothing manufacturing and washing POIs. Unlike in urban areas, automobile service POIs, packaging POIs and textile POIs had no significant relationship with the MDII, which may be related to the population and economic development scale. The results emphasize the importance of investigating MP occurrence and sources in coastal agricultural areas to promote the effective management of MPs and plastic emissions in land-sea transition zones., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
26. Rapid Method To Determine 137 Cs, 237 Np, and Pu Isotopes in Seawater by SF-ICP-MS.
- Author
-
Zhang S, Liu Z, Yang G, Zheng J, Pan S, Aono T, and Sakaguchi A
- Abstract
Neptunium-237, owing to its long half-life ( t
1/2 year) and similar conservatism to6 year) and similar conservatism to137 Cs for water mass circulation studies on decades and even longer time scales. A new method for the determination of137 Cs for water mass circulation studies on decades and even longer time scales. A new method for the determination of137 Np, and Pu isotopes in seawater samples was proposed to solve the difficulty of237 Np analysis in seawater. The developed method includes the separation technique of ammonium phosphomolybdate (AMP) adsorption for237 Cs and anion exchange chromatography for137 Np and Pu, a measurement technique of gamma spectrometry for237 Cs and SF-ICP-MS for137 Np and Pu isotopes.237 Np and Pu isotopes.242 Np and237 Pu of 1.02 ± 0.06 (242 = 2) was obtained by implementing sophisticated control of the redox system and chromatographic elution optimization. The analytical results for the International Atomic Energy Agency Certified Reference Materials (IAEA-443) agreed with the reference values, showing chemical yields of 65-88%, U decontamination factor above 10 k level, and improved sample throughput (5 days for 12 samples). Meanwhile, the lower method detection limits (MDLs) of6 level, and improved sample throughput (5 days for 12 samples). Meanwhile, the lower method detection limits (MDLs) of237 Pu, and239 Pu, and240 , 0.065, and 0.15 μBq L-3 for 15 L seawater, respectively. Results obtained by the developed method can be used to evaluate the impact on the marine ecological system of the planned marine discharge of Fukushima decontaminated wastewater. Working toward that purpose, we are the first to report the-1 Np activity concentration in Pacific Ocean seawater sampled near the station site, and we obtained the value of 0.122-0.154 μBq L237 Np activity concentration in Pacific Ocean seawater sampled near the station site, and we obtained the value of 0.122-0.154 μBq L-1 .- Published
- 2023
- Full Text
- View/download PDF
27. Role of microplastics in microbial community structure and functions in urban soils.
- Author
-
Zhou Y and Zhou S
- Subjects
- Humans, Plastics, Soil Microbiology, Soil chemistry, Microplastics pharmacology, Microbiota
- Abstract
Evidence from the laboratory suggests that microplastics (MPs) can harm soil microorganisms, affecting the structures and functions of microbial communities. The impact of soil MPs on microbes in actual urban environments with high human activity levels, however, has not been well reported. To investigate the MP effect on urban soil microorganisms under complex scenarios, we analyzed 42 soil samples from standardized plots of 7 urban functional zones. We report that urban green spaces are important for studying microbial diversity in the study area, and they also contribute to the global homogenization of soil microbes and genes. Bacterial communities in soils enriched with various MPs showed greater differences in OTUs than fungi. Compared to low-MP soils, most ARGs and nutrient cycling genes had similar or slightly lower abundances in soils with high levels of MPs. The coupling of pollutant factors with MPs as independent variables had significant explanatory power for both positive and negative correlations in PLS-PM analysis. Specifically, PET and PP MPs explained 3.54% and 6.03%, respectively, of the microbial community and functional genes. This study fills knowledge gaps on the effects of MPs on urban soil microbial communities in real environments, facilitating better management of urban green spaces., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
28. Environmental hazard assessment and metal contamination in coastal sediments.
- Author
-
Ayyamperumal R, Kumari K, Gandhi MS, Huang X, Chengjun Z, Nazir N, Li F, and Das P
- Subjects
- Ecosystem, India, Lead, Geologic Sediments, Risk Assessment, Environmental Monitoring methods, Water Pollutants, Chemical analysis, Metals, Heavy analysis
- Abstract
In order to reduce contamination levels from diverse sources, it is important to understand the factors affecting the natural ecosystems that are impacted by coastal and marine pollution. In this study, we used GIS and remote sensing techniques to investigate and evaluate the distribution of heavy metals (Fe, Mn, Zn, Cr, Pb, Co, and Cu) in surface sediments along Tamil Nadu's East Coast (from Besant Nagar to Sathurangapattinam). The CF and Igeo of metals indicate that sediments contain no evidence of Fe, Mn, or Zn metal pollution in the sediments, with only mild contamination from Co, Cu, and Pb. In contrast, the sediment samples were found to be significantly contaminated with Cr. Heavy metal contamination occurs in the following order, according to our research: Cr > Pb > Cu > Co > Mn > Zn > Fe. Except for sites 8, 10, 11, and 13, where PLI>1 implies that there is no pollution in this area, the PLI values show that most of the locations are contaminated. The ecological risk index (ERI) values for five metals in the study areas are as follows: Cr > Pb > Cu > Mn > Zn. The sediment samples fall into the low-risk and highly polluted to dangerous sediment categories for SPI, according to the Risk index (RI). Based on the Mean Effect Range-Median Quotient (M-ERM-Q), Cu, Pb, Zn, and Cr metals in the research region have a 9-21% probability of being harmful. Statistical approaches show that the majority of heavy metals in sediments are of natural origin. The spatial distribution of heavy metals in surface sediments provides the conceptual framework for practical strategies to protect coastal areas. Many shreds of evidence indicate that anthropogenic inputs from the surrounding land area are primarily responsible for the deposition of these heavy metals in the coastal zone., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
29. Quantifying climate variability and regional anthropogenic influence on vegetation dynamics in northwest India.
- Author
-
Banerjee A, Kang S, Meadows ME, Xia Z, Sengupta D, and Kumar V
- Subjects
- Humans, Climate Change, India, Ecosystem, Soil
- Abstract
To explore the spatio-temporal dynamics and mechanisms underlying vegetation cover in Haryana State, India, and implications thereof, we obtained MODIS EVI imagery together with CHIRPS rainfall and MODIS LST at annual, seasonal and monthly scales for the period spanning 2000 to 2022. Additionally, MODIS Potential Evapotranspiration (PET), Ground Water Storage (GWS), Soil Moisture (SM) and nighttime light datasets were compiled to explore their spatial relationships with vegetation and other selected environmental parameters. Non-parametric statistics were applied to estimate the magnitude of trends, along with correlation and residual trend analysis to quantify the relative influence of Climate Change (CC) and Human Activities (HA) on vegetation dynamics using Google Earth Engine algorithms. The study reveals regional contrasts in trends that are evidently related to elevation. An annual increasing trend in rainfall (21.3 mm/decade, p < 0.05), together with augmented vegetation cover and slightly cooler (-0.07 °C/decade) LST is revealed in the high-elevation areas. Meanwhile, LST in the plain regions exhibit a warming trend (0.02 °C/decade) and decreased in vegetation and rainfall, accompanied by substantial reductions in GWS and SM related to increased PET. Linear regression demonstrates a strongly significant relationship between rainfall and EVI (R
2 = 0.92), although a negative relationship is apparent between LST and vegetation (R2 = -0.83). Additionally, increased LST in the low-elevation parts of the study area impacted PET (R2 = 0.87), which triggered EVI loss (R2 = 0.93). Moreover, increased HA resulted in losses of 25.5 mm GSW and 1.5 mm SM annually. The relative contributions of CC and HA are shown to vary with elevation. At higher elevations, CC and HA contribute respectively 85% and 15% to the increase in EVI. However, at lower elevations, reduced EVI is largely (79%) due to human activities. This needs to be considered in managing the future of vulnerable socio-ecological systems in the state of Haryana., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
30. Effects of microplastics on the toxicity of co-existing pollutants to fish: A meta-analysis.
- Author
-
Yuan F, Chen H, Ding Y, Wang Y, Liao Q, Wang T, Fan Q, Feng Z, Zhang C, Fu G, and Zou X
- Subjects
- Animals, Microplastics toxicity, Plastics analysis, Ecosystem, Fishes, Environmental Pollutants analysis, Water Pollutants, Chemical toxicity, Water Pollutants, Chemical analysis
- Abstract
Aquatic ecosystems are among the main destination for microplastics (MPs) in the environment. MPs that enter aquatic ecosystems can contribute to pollution together with other co-existing pollutants. However, whether such pollution results in higher or lower toxicity to fish than that caused by co-existing pollutants alone remains controversial. This study aimed at closing this research gap based on 1380 biological endpoints under the background of environmental MP concentrations collected from 55 laboratory studies. Overall, MPs in co-existing pollutant solutions significantly increased the toxicity to fish. Specifically, MPs elevated negative effects on the immune system, metabolism, and oxidative damage. Subgroup analysis indicated that changes in toxicity were related to fish life stage and MP size, but not to co-existing pollutant or MP type. Meta-regression analysis indicated that changes in toxicity were not related to the logarithm of the octanol-water partition coefficient (logKow) or exposure time. Finally, the differences between laboratory research and the actual aquatic environment were discussed from four aspects: MPs, co-existing pollutants, environmental factors, and experimental objects. Our study provides a basis for further understanding the potential impact of MPs on aquatic organisms from a combined pollution perspective. Moreover, our results can provide a reference for the conservation and management of aquatic ecosystems., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
31. Plant Gender Affects Soil Fungal Microbiota Associated with Welwitschia mirabilis, an Unusual Desert Gymnosperm.
- Author
-
Doniger T, Kerfahi D, Wachtel C, Marais E, Maggs-Kölling G, Sherman C, Adams JM, and Steinberger Y
- Subjects
- Cycadopsida, Soil chemistry, Plants microbiology, Soil Microbiology, Mycobiome, Mirabilis, Ascomycota
- Abstract
In a recent study, we found a distinct soil bacterial community associated with male and female plants of the desert gymnosperm Welwitschia mirabilis. In this subsequent study, we also found that the soil fungal community associated with Welwitschia differs between male and female plants, and between unvegetated areas and the soil under plants. Site location, pH, and soil moisture also had an important influence on the composition of the fungal community. A number of Ascomycota and Chytrid species were found to be distinct indicators of male and female plants, respectively, but there was no overall difference at the phylum level or in terms of diversity. The unvegetated areas between plants also differed in terms of several Ascomycota OTUs. Network connectivity of the fungal communities was found to be higher under both male and female Welwitschia plants than in unvegetated control areas. As with the bacterial community, it is unclear what processes produce the gender-distinct fungal community, and also the more general plant-associated community, and also what the effects on the biology of the plants are. One possibility behind the gender-related difference in fungal community is that there are differences in the production of pollen or nectar between the two plant genders, affecting the below-ground soil community., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2023
- Full Text
- View/download PDF
32. Whole community and functional gene changes of biofilms on marine plastic debris in response to ocean acidification.
- Author
-
Kerfahi D, Harvey BP, Kim H, Yang Y, Adams JM, and Hall-Spencer JM
- Subjects
- Humans, Plastics, Hydrogen-Ion Concentration, Ocean Acidification, Carbon Dioxide, Biofilms, Seawater, Diatoms genetics
- Abstract
Plastics are accumulating in the world's oceans, while ocean waters are becoming acidified by increased CO
2 . We compared metagenome of biofilms on tethered plastic bottles in subtidal waters off Japan naturally enriched in CO2 , compared to normal ambient CO2 levels. Extending from an earlier amplicon study of bacteria, we used metagenomics to provide direct insights into changes in the full range of functional genes and the entire taxonomic tree of life in the context of the changing plastisphere. We found changes in the taxonomic community composition of all branches of life. This included a large increase in diatom relative abundance across the treatments but a decrease in diatom diversity. Network complexity among families decreased with acidification, showing overall simplification of biofilm integration. With acidification, there was decreased prevalence of genes associated with cell-cell interactions and antibiotic resistance, decreased detoxification genes, and increased stress tolerance genes. There were few nutrient cycling gene changes, suggesting that the role of plastisphere biofilms in nutrient processes within an acidified ocean may not change greatly. Our results suggest that as ocean CO2 increases, the plastisphere will undergo broad-ranging changes in both functional and taxonomic composition, especially the ecologically important diatom group, with possible wider implications for ocean ecology., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)- Published
- 2023
- Full Text
- View/download PDF
33. Identifying spatial agglomeration and driving forces of land use by green industries: a case study of Jiangsu Province, China.
- Author
-
Wang Q, Zhao XF, Lin SH, Huang XJ, and Lv JC
- Subjects
- Industry, Industrial Development, Economic Development, China, Urbanization, Conservation of Natural Resources
- Abstract
In response to China's aims of becoming "carbon-neutral," the development of green industries such as renewable energy and recycling has flourished. Based on 2015 and 2019 data, this study uses spatial autocorrelation to analyze the evolution of land use by the green industries in Jiangsu Province. The Geodetector model was also applied to identify the driving factors underlying these spatial patterns. The spatial variability of green industrial land use in Jiangsu Province is significant, with the land-use area gradually decreasing from Southern to Northern Jiangsu. In terms of spatial-temporal changes, there is an increase in land use and a trend of expansion in the central and northern regions of Jiangsu. Land use by green industries in the province exhibits a more significant spatial clustering pattern but with a weakened clustering effect. The clustering types are mainly H-H and L-L, with the H-H type distributed mainly in the Su-Xi-Chang region and the L-L type distributed mainly in the Northern Jiangsu region. The levels of technology, economic development, industrialization, and industrial diversification are important individual driving factors, and the interaction among the different factors enhances their driving forces. This study suggests that spatial spillover effects should be focused to promote the coordinated development of regional energy-saving and environmental protection industries. At the same time, joint efforts should be made from the aspects of resources, government, economy, and related industries to promote the agglomeration of land for energy-saving and environmental protection industries., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2023
- Full Text
- View/download PDF
34. Distinct responses of soil methanotrophy in hummocks and hollows to simulated glacier meltwater and temperature rise in Tibetan glacier foreland.
- Author
-
Zhu X, Deng Y, Hernández M, Fang J, Xing P, and Liu Y
- Subjects
- Tibet, Temperature, Oxidation-Reduction, Water, Methane, DNA, Soil Microbiology, Soil, Ice Cover
- Abstract
Glacier foreland soils are known to be essential methane (CH
4 ) consumers. However, global warming and increased glacier meltwater have turned some foreland meadows into swamp meadows. The potential impact of this change on the function of foreland soils in methane consumption remains unclear. Therefore, we collected Tibetan glacier foreland soils in the non-melting season from typical microtopography in swamp meadows (hummock and hollow). Three soil moisture conditions (moist, saturated, and submerged) were set by adding glacier runoff water. Soil samples were then incubated in the laboratory for two weeks at 10 °C and 20 °C. About 5 % of13 CH4 /12 CH4 was added to the incubation bottles, and daily methane concentrations were measured. DNA stable isotope probing (DNA-SIP) and high-throughput sequencing were combined to target the active methanotroph populations. The results showed that type Ia methanotrophs, including Crenothrix, Methylobacter, and an unclassified Methylomonadaceae cluster, actively oxidized methane at 10 °C and 20 °C. There were distinct responses of methanotrophs to soil moisture rises in hummock and hollow soils, resulting in different methane oxidation potentials. In both hummock and hollow soils, the methane oxidation potential was positively correlated with temperature. Furthermore, saturated hummock soils exhibited the highest methane oxidation potential and methanotroph populations, while submerged hollow soils had the lowest. This suggests that the in-situ hummock soils, generally saturated with water, are more essential than in-situ hollows, typically submerged in water, for alleviating the global warming potential of swamp meadows in the Tibetan glacier foreland during the growing season., Competing Interests: Declaration of competing interest The authors declare that the research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2023
- Full Text
- View/download PDF
35. A PES framework coupling socioeconomic and ecosystem dynamics from a sustainable development perspective.
- Author
-
Li F, Liu H, Wu S, Wang Y, Xu Z, Yu P, and Yan D
- Subjects
- Conservation of Natural Resources methods, Socioeconomic Factors, Antarctic Regions, China, Ecosystem, Sustainable Development
- Abstract
Payments for ecosystem services (PES) are becoming a global ecological protection strategy used to promote sustainable social and economic development. However, the current PES research and applications are often local and one-sided. The lack of a unified framework for PES results in a high policy cost and low ecological and social benefits. A large number of local PES experiences need to be comprehensively analyzed to construct a unified PES framework, which can provide support for the implementation and optimization of nature conservation policy in different regions of the world. Here, we combined natural language processing methods to analyze 1919 global studies on PES. We obtained the topics and spatiotemporal distributions of PES, as well as the compensation modes of hotspot ecosystem services in 114 countries worldwide. PES have been studied in 80% of the world (excluding Antarctica), but the research topics and distributions are very uneven. We found a disconnection between PES socioeconomic strategies and knowledge of natural ecosystem dynamics. Therefore, the knowledge and experience of PES must be exchanged globally, and PES need to be further integrated with the sustainable development goal (SDG) framework. We propose a PES framework that couples socioeconomic and ecosystem dynamics and be oriented toward sustainable development to make comprehensive management decisions. On this basis, a consistent PES solution may be provided for future theoretical research and implementation strategies of conservation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
36. Ecological restoration for sustainable development in China.
- Author
-
Fu B, Liu Y, and Meadows ME
- Abstract
Facing the need for transdisciplinary research to promote ecological restoration that achieves both social and ecological benefits, research on past restoration efforts that have directly or indirectly contributed to regional or national sustainable development warrants reassessment. Using China as an example, in this review, we address three basic research questions that can be summarized as follows: ecological restoration-of what, for whom and to what purpose? Accordingly, a 'landscape pattern-ecosystem service-sustainable development' co-evolutionary framework is proposed here to describe landscape-scale ecological restoration and its impact on landscape patterns and ecological processes, ecosystem services for human well-being, sustainable livelihoods and socioeconomic development. From the strategic pattern of national ecological security to the pattern of major projects to protect and restore major national ecosystems, the spatial pattern of China's ecological restoration is more geographically integrative. From major function-oriented zoning to systematic ecological protection and restoration, and for the purpose of achieving the Beautiful China Initiative, there are three stages of ecosystem services management: classification, synergy and integration, respectively. The difference in geographic processes should be considered in the key requirements of ecological restoration for China's five national strategies for regional sustainable-development strategies. Deepening understanding of the relationship between humans and nature in different geographical contexts is a scientific prerequisite to support policymaking related to ecological restoration. To promote greater harmony between humans and nature, we propose four important research directions: (i) understanding coupling processes among key components, (ii) identifying ecosystem service flows, (iii) evaluating social-ecological benefits and (iv) supporting adaptive management for regional sustainable development., (© The Author(s) 2023. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd.)
- Published
- 2023
- Full Text
- View/download PDF
37. Assessment on the pollution level and risk of microplastics on bathing beaches: a case study of Liandao, China.
- Author
-
Wu X, Zhong C, Wang T, and Zou X
- Subjects
- Humans, Plastics analysis, Nylons, Bathing Beaches, Environmental Monitoring methods, China, Microplastics, Water Pollutants, Chemical analysis
- Abstract
Microplastic pollution on bathing beaches threatens the health of human beings and coastal organisms. There is a lack of assessment on the level of microplastic pollution and the health risk associated with plastics. As one of the earliest open bathing beaches in China, Liandao is well known as the two high-quality beaches. However, little is known about the extent of microplastic pollution on these bathing beaches. Based on the analysis of microplastic pollution abundance, distribution, shape, size, color, and composition at the Liandao bathing beaches, this study puts forward a novel approach to comprehensively evaluate the microplastic pollution level and risk level by using the Nemerow pollution index (NPI) and polymer hazard index (PHI). The results show that the average abundance of microplastics on the Liandao bathing beaches is 135.42 ± 49.58 items/kg; the main shapes are fibers, fragments, and granules. Most of the microplastics are transparent, brown, and black, accounting for 71.54%, and they have an average particle size of 0.63 ± 0.43 mm. The main components are PE, PP, PS, PET, and nylon, of which nylon appears in the highest proportion (54.77%). The microplastic NPI and PHI values are 0.38 and 74.81, respectively, indicating that the pollution level and health risk index of microplastics on the Liandao bathing beaches are both low. With the increase in population and per capita consumption, plastic waste generated on land will continue to increase. Finally, this study puts forward some suggestions regarding microplastic monitoring, plastic waste management, and environmental attitudes and behavior., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
- Published
- 2023
- Full Text
- View/download PDF
38. How Outstanding Universal Value Attractiveness and Tourism Crowding Affect Visitors' Satisfaction?
- Author
-
Nian S, Chen M, Zhang X, Li D, and Ren J
- Abstract
A World Heritage Site is a masterpiece of mankind and/or nature that possesses outstanding universal value (OUV). In this regard, the 5Cs strategic objectives (credibility, communication, capacity-building, conservation, and community) set by the World Heritage Committee have become a main issue for WHS sustainable development. As one of the key stakeholders of WHS, tourist's perceived OUV attractiveness, congestion, and attitudinal behavior have significant implications for heritage protection and tourism's sustainable development. Based on the perspectives of OUV attractiveness and perceived tourist crowding, and taking into account destination attachment, the influencing factors and mechanisms of tourist satisfaction are investigated. In view of the 536 questionnaire responses from tourists of Mount Sanqingshan National Park, the structural equation modeling approach was employed to study tourist satisfaction. The conclusions were sketched: (1) tourist crowding perception did not have a significant negative effect on OUV attractiveness; destination attachment, and tourist satisfaction, and the degree of crowding perception was low; (2) the OUV attractiveness has a significant positive influence on destination attachment and tourist satisfaction, which fully highlights the charm of OUV and its important role in shaping tourists' attitudes/behaviors; (3) destination attachment has a significant positive effect on tourist satisfaction, indicating that tourists' heritage-place attachment contributes to tourist satisfaction. Finally, the analysis of tourism crowding, OUV, and the satisfaction framework proposed broaden the horizons of visitor satisfaction research, which is also a positive response to the strategic objectives of the 5Cs of WHS, with some practical implications for heritage preservation and visitor management in World Heritage Sites.
- Published
- 2023
- Full Text
- View/download PDF
39. Thirty-year changes of the coastlines, wetlands, and ecosystem services in the Asia major deltas.
- Author
-
Liu Y, Li J, Sun C, Wang X, Tian P, Chen L, Zhang H, Yang X, and He G
- Subjects
- Rivers, Asia, China, Wetlands, Ecosystem
- Abstract
Coastal zones are usually composed of coastlines and coastal wetlands and are among the most productive and dynamic ecosystems. However, the deltas are seldom detected and compared in detail at the continental scale to investigate the spatiotemporal evolution of coastline migration and coastal wetlands. Here we detected and compared the spatiotemporal changes in coastlines, wetlands, and ecosystem services in major deltas in Asia, including the Yellow River Delta (YRD), Yangtze River Delta (YAD), Pearl River Delta (PRD), Red River Delta (RRD), Mekong River Delta (MERD), Chao Phraya River Delta (CPRD), Mahanadi River Delta (MARD), Krishna River Delta (KRD), and Indus River Delta (IRD). We used time series remote sensing images from 1990 to 2019 to derive coastline and wetland information for the nine coastal zones. The ecosystem service value coefficients were applied to explore the ecosystem services characteristics of wetland changes in coastal areas. We found that the coastlines of the deltas in the study area changed less in the bedrock and sandy coasts, while the coastlines in the silty delta coasts changed more from 1990 to 2019. The interannual dynamics of coastal wetland areas in nine major deltas over the nearly 30 years can be divided into three periods: decreasing variability (1990-2005), increasing variability (2005-2015), and increasing volatility (2015-2019). Ecosystem services had an overall downward trend. These findings complement the official database of coastal planning and have substantial guiding implications for adjusting coastal management regulation policies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
40. Stimulus-Organism-Response Framework: Is the Perceived Outstanding Universal Value Attractiveness of Tourists Beneficial to World Heritage Site Conservation?
- Author
-
Nian S, Li D, Zhang J, Lu S, and Zhang X
- Subjects
- Sustainable Development, Knowledge, Parks, Recreational, Intention, Attitude
- Abstract
Tourists have been attracted to world heritage sites (WHSs) by their Outstanding Universal Value (OUV). In view of the Stimulus-Organism-Response (S-O-R) framework and the theory of attitude and behavior, by employing 563 tourist samples from Mount Sanqingshan National Park, and using structural equation modeling, we examine tourist behavioral intention for heritage conservation, and the following conclusions were drawn: (1) the S-O-R theory revealed the behavioral intentions of tourists to protect WHSs; (2) as a stimulus, tourists' value perception and destination attachment were positively affected by the OUV attractiveness, and their perceived value had a positive influence on heritage conservation, although the hypothesis of destination attachment to heritage conservation was not supported; (3) heritage-conservation education and knowledge positively influenced tourists' behavioral intentions towards heritage protection, and tourists' heritage protection attitude had a positive influence on their behavioral intention; and (4) a framework of the influence mechanism for tourists' heritage conservation based on the S-O-R theory was proposed, while tourists' cognitive and affective attitudes impacted on heritage protection intention which, in turn, further enhanced the tourists' perception of the OUV. Conclusively, the measures and implications were proposed for improving conservation and management of WHSs, in particular to achieve the sustainable development of the tourist industry and world heritage sites.
- Published
- 2023
- Full Text
- View/download PDF
41. Factors Associated with Housing Damage Caused by an EF4 Tornado in Rural Areas of Funing, China.
- Author
-
Qiao P, Chen W, Zhao J, Gao J, and Zhai G
- Subjects
- Humans, Housing, China epidemiology, Water, Tornadoes, Disasters
- Abstract
Rural areas are vulnerable to natural disasters and tend to suffer severe losses. An EF4 tornado occurred in Funing on 23 June 2016, killing 99 people, injuring at least 846 people, and destroying more than 2000 houses. Using a multinomial logistic regression model, this study explored the influencing factors between housing damage and variables of building conditions, tornado intensity, and village environmental factors. The results show that 2-story houses and masonry houses were more likely to be slightly damaged or be in a dangerous state. Furthermore, the building area was positively related to houses in two categories: slight damage (SD) and dangerous and requiring immediate repair (DR), indicating that the larger or taller the house, the more severe the damage. In terms of tornado intensity, houses classified as SD were more likely to be hit by EF4 tornados than by EF3 tornados, and houses were damaged more by EF1 or EF2 tornados. This finding demonstrates that the level of housing damage was not strongly correlated with the tornado intensity. Slightly damaged houses exhibited the highest correlation with environmental factors. The proportion of slightly damaged houses was positively correlated with the water area in the village, unlike the proportion of houses in the DR and unable to be repaired (UR) categories. Moreover, the larger the water area of a village, the less housing damage it suffered. These findings provide new insights into minimizing housing damage in wind disasters to improve disaster prevention planning in rural areas.
- Published
- 2022
- Full Text
- View/download PDF
42. Environmental effects on trace elements in the fingernails of centenarians and their offspring.
- Author
-
Hao Z, Zhang C, Lin B, Chen Z, Li Y, Zou X, Li H, Zheng F, and Cao J
- Subjects
- Aged, Aged, 80 and over, Humans, Middle Aged, Centenarians, Environmental Monitoring, Lead, Longevity, Nails chemistry, Trace Elements analysis
- Abstract
Bio-monitoring is commonly used to investigate trace elements, and the human nail provides an ideal medium for such testing. Toxic and essential trace metals (Cd, Pb, Fe, and Se) in the fingernails of participants from the Hainan Province were investigated. Samples included 136 centenarians and 197 offspring (101 older adult children and 96 middle-aged grandchildren) who were also sampled for comparison. As a hotspot for longevity, participants in the Hainan Province were found to have high essential nutrients of Fe and Se, and lacked the toxic element Pb. A similar trend was found for trace elements in soil and rice in the Hainan Province. The trace elements preserved in nails revealed dietary and environmental influences that varied among different generations. For the grandchildren's generation, the environment played an important role in elements in their nails, and a significant correlation and linear relationships were found, especially for Fe and Se. As the participants increased in age (from the grandchildren to the centenarians), the correlation between various elements decreased. For centenarians, the influence of beneficial or harmful properties of the elements became more important than their environment. The results also pointed to the important role of trace elements in human health, especially Fe and Se as essential elements. This study can provide information on the factors that influence the existence of trace elements in the human body and demonstrate the advantage of using the human fingernail in bio-monitoring., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
43. Arable land and water footprints for food consumption in China: From the perspective of urban and rural dietary change.
- Author
-
Yan D, Wu S, Tang Y, Zhu J, Zhou S, and Xu Z
- Subjects
- Agriculture, China, Humans, Water, Water Resources, Conservation of Natural Resources methods, Rural Population
- Abstract
Since the adoption of the open-door policy, the Chinese dietary pattern has changed greatly. Based on the dietary changes, this study analyzed the arable land and water footprints (WFs) for the food consumption of urban and rural residents in China. The results showed that the arable land demand and WFs for meat, vegetable oil, soybeans and liquor exceeded those for other foods, and the per capita arable land and WFs for food consumption of urban residents were higher than those of rural residents. The total arable land and WFs for the food consumption of residents increased by 16.9 million ha (from 91.1 to 108 million ha) and 214.5 billion m
3 (from 457.9 to 672.4 billion m3 ), respectively, from 1983 to 2017. Specifically, the total arable land and WFs for the food consumption of urban residents increased by 45.9 million hm2 (from 22.6 to 68.5 million hm2 ) and 318.3 billion m3 (from 113.2 to 431.5 billion m3 ), respectively. Additionally, those of rural residents decreased by 29.7 million hm2 (from 69.2 to 39.5 million hm2 ) and 103.9 billion m3 (344.8 to 240.9 billion m3 ), respectively, mainly due to the migration of the rural population to cities and the reductions in per capita arable land and WFs due to increased crop yields. The arable land and blue WFs required for food consumption will reach 127.7 million hm2 and 221.1 billion m3 , respectively, in 2030. However, these values will be reduced by approximately 23% and 20%, respectively, to 98.9 million hm2 and 177.8 billion m3 under a balanced dietary pattern. Measures such as improving the investment in agricultural research and development, advocating a balanced diet, and increasing the import of resource-intensive foods could alleviate the pressure on land and water resources., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
44. Integrating indices based on different chemical extractions and bioaccumulation in Bellamya aeruginosa to assess metal pollution and ecological risk in sediment.
- Author
-
Yu Z, Liu E, Lin Q, Zhang Q, Yuan H, Zhang E, and Shen J
- Subjects
- Animals, Bioaccumulation, Cadmium, China, Environmental Monitoring methods, Geologic Sediments chemistry, Lakes chemistry, Lead, Pseudomonas aeruginosa, Risk Assessment, Gastropoda, Metals, Heavy analysis, Water Pollutants, Chemical analysis
- Abstract
Various indices based on metal chemical data are used to evaluate pollution and ecological risk, but the consistency of the assessment results is usually unsatisfactory, and it is unclear if the ecological risk from sediment metals is accurately represented in in situ zoobenthos. Herein, the pollution and ecological risk associated with As, Cd, Cr, Cu, Ni, Pb and Zn in the sediments of two adjacent lakes (Datun (DT) and Changqiao (CQ)) were comprehensively evaluated by integrating metal concentrations, chemical forms and bioaccumulation in Bellamya aeruginosa (B. aeruginosa). The metal concentrations and chemical compositions varied widely in the sediments. Over 50% of the Cd, Pb and Zn in the sediments was present in bioavailable forms, followed by 28% of Cu and less than 25% of As, Cr and Ni. According to the enrichment factor (EF) and concentration enrichment ratio (CER) assessments, Cr and Ni were natural in origin, while the other metals were at minor to extremely high pollution levels, with average EFs of 1.5-77.6 and CERs of 1.1-113.4. The pollution levels for Cd, Cu and Pb from the EF and CER assessments were similar, while those for As and Zn were higher according to CER than EF (p = 0.05), likely due to the baseline underestimation associated with the potential diagenetic remobilization of bioavailable metals. The ecological risk index (Er), sediment quality guidelines (SQGs) and risk assessment code (RAC) showed a high eco-risk for Cd, while no similar risk was found for the other metals. By integrating risk indices with the chemical forms and pollution levels of metals, we deduced high eco-risks for As and Pb and moderate eco-risks for Cu and Zn in DT Lake and moderate eco-risks for As, Pb and Zn in CQ Lake. The other metals in the sediments of the two lakes presented low eco-risks. No significant positive correlations (p = 0.05) between metal accumulation in B. aeruginosa and the indices of pollution and eco-risk were observed except for the case of As, implying that measuring the metal concentrations in B. aeruginosa would not accurately characterize the metal pollution and ecological risk of sediments., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
45. Study on the advanced nitrogen removal under low temperature by biofilm on weak magnetic carriers.
- Author
-
Chen S, Yang D, Wang Q, Huang X, Ren H, and Xu K
- Subjects
- Biofilms, Bioreactors, Magnetic Phenomena, Temperature, Wastewater analysis, Denitrification, Nitrogen
- Abstract
The advanced nitrogen removal under low temperature is inhibited because of reduction of the microbial activity. Packed bed reactors filled with different magnetic carriers (0, 0.3, 0.6, 0.9 mT) were constructed to enhance advanced denitrification under low temperature (5 ℃). Results showed that 0.3 and 0.9 mT carriers significantly improved denitrification, indicating the "window" effect. Total nitrogen removals were increased by 6.96% and 8.25%, and NO
2 accumulation decreased by 25.70% and 13.90% in 0.3 and 0.9 mT reactors, respectively. Analysis of enzyme activity and electron transport chain showed that 0.3 mT carrier mainly increased NIR activity by improving compound III and cytC abundance while 0.9 mT carrier mainly increased NAR activity by improving compound I and NADH abundance, indicating different pathways. Similar microbial community in 0.3 and 0.9 mT reactors were revealed. Overall, weak magnetic carriers can be used to enhance advanced nitrogen removal under low temperature.- accumulation decreased by 25.70% and 13.90% in 0.3 and 0.9 mT reactors, respectively. Analysis of enzyme activity and electron transport chain showed that 0.3 mT carrier mainly increased NIR activity by improving compound III and cytC abundance while 0.9 mT carrier mainly increased NAR activity by improving compound I and NADH abundance, indicating different pathways. Similar microbial community in 0.3 and 0.9 mT reactors were revealed. Overall, weak magnetic carriers can be used to enhance advanced nitrogen removal under low temperature., (Copyright © 2022 Elsevier Ltd. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
46. Microplastics in urban soils of Nanjing in eastern China: Occurrence, relationships, and sources.
- Author
-
Zhou Y, Wang J, Zou M, Yin Q, Qiu Y, Li C, Ye B, Guo T, Jia Z, Li Y, Wang C, and Zhou S
- Subjects
- China, Environmental Monitoring, Plastics, Soil, Microplastics, Water Pollutants, Chemical analysis
- Abstract
Although microplastic (MP) pollution has been defined as a new global challenge by the United Nations Environment Programme, their abundance and composition has only been studied in-depth within farmland soil, while minimal attention has been placed on urban soil contamination. Accordingly, within the current study, MP abundance and composition is investigated within urban soil from green spaces in Nanjing, eastern China. The average MP abundance in soil was 461 ± 222 items/kg and primarily comprised fibers (39.1%) and fragments (37.7%). MPs <1000 μm in size accounted for 83.7% of the total content and white MPs were the most abundant (26.5%). The dominant polymers were polyethylene glycol terephthalate (32.0%) and polypropylene (20.5%). Moreover, relationship network analysis generated three distinct MP modules based on community similarity. Indeed, the degree of similarity increased by ∼26.8% per kilometer. Furthermore, application of a forward selective optimal multiple regression model identified clay, sand, longitude, and points of interest for recycling bins (RecyclePOI) as the primary spatial and soil environmental factors affecting MP abundance and composition. Additionally, five potential sources of MPs were identified based on the MP diversity integrated index fitting results, and point of interest density (MDII-POI) source analysis (R
2 = 0.21-0.62; P < 0.05). In particular, the point of interest of express delivery points (ExpressPOI) were important sources of plastic emissions as they are widely distributed throughout urban and fringe areas. Collectively, the findings of this study provide novel insights regarding quantitative source appointment and regional ecological control of MPs in urban soil., (Copyright © 2022 Elsevier Ltd. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
47. Fungi stabilize multi-kingdom community in a high elevation timberline ecosystem.
- Author
-
Yang T, Tedersoo L, Liu X, Gao GF, Dong K, Adams JM, and Chu H
- Abstract
Microbes dominate terrestrial ecosystems via their great species diversity and vital ecosystem functions, such as biogeochemical cycling and mycorrhizal symbiosis. Fungi and other organisms form diverse association networks. However, the roles of species belonging to different kingdoms in multi-kingdom community networks have remained largely elusive. In light of the integrative microbiome initiative, we inferred multiple-kingdom biotic associations from high elevation timberline soils using the SPIEC-EASI method. Biotic interactions among plants, nematodes, fungi, bacteria, and archaea were surveyed at the community and network levels. Compared to single-kingdom networks, multi-kingdom networks and their associations increased the within-kingdom and cross-kingdom edge numbers by 1012 and 10,772, respectively, as well as mean connectivity and negative edge proportion by 15.2 and 0.8%, respectively. Fungal involvement increased network stability (i.e., resistance to node loss) and connectivity, but reduced modularity, when compared with those in the single-kingdom networks of plants, nematodes, bacteria, and archaea. In the entire multi-kingdom network, fungal nodes were characterized by significantly higher degree and betweenness than bacteria. Fungi more often played the role of connector, linking different modules. Consistently, structural equation modeling and multiple regression on matrices corroborated the "bridge" role of fungi at the community level, linking plants and other soil biota. Overall, our findings suggest that fungi can stabilize the self-organization process of multi-kingdom networks. The findings facilitate the initiation and carrying out of multi-kingdom community studies in natural ecosystems to reveal the complex above- and belowground linkages., Competing Interests: The authors declare no conflict of interest., (© 2022 The Authors. iMeta published by John Wiley & Sons Australia, Ltd on behalf of iMeta Science.)
- Published
- 2022
- Full Text
- View/download PDF
48. Source and distribution characteristics of 239, 240, 241 Pu, 237 Np and 134, 137 Cs in sediments in the Northwest and Central Equatorial Pacific after the Fukushima nuclear accident.
- Author
-
Wang F, Zheng J, Aono T, Pan S, and Men W
- Subjects
- Cesium Radioisotopes analysis, Japan, Fukushima Nuclear Accident, Plutonium analysis, Radiation Monitoring, Water Pollutants, Radioactive analysis
- Abstract
To understand the possible influence of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident on the deep sea, as well as the geochemical behavior and transport of radionuclides,
134 Cs,137 Cs,239, 240 Pu,241 Pu, and237 Np were measured in the abyssal sediments of the Northwest Pacific (NWP) and Central Equatorial Pacific (CEP) Ocean. Data on the characteristics of these sediments obtained after the FDNPP accident are extremely rare, especially in the NWP subtropical gyre (NPSG) region. FDNPP-derived radio-Cs (134 Cs,137 Cs) arrived at the open sea floor of the NWP before 2018 but was only found in the Kuroshio-Oyashio Extension (KOE) region. No FDNPP-derived Pu was detected in the abyssal sediments of the NWP or CEP. Pu in the NWP mainly originated from global fallout and the Pacific Proving Ground (PPG) close-in fallout, except for at station WP1 (39°N in the KOE region), where an abnormal but non-FDNPP-derived Pu signal was detected. Pu in the eastern CEP sediment was less affected by the PPG close-in fallout from the Marshall Islands and was mainly derived from global fallout, with some close-in fallout from the Johnston Atoll test. The KOE region was the area most affected by PPG close-in fallout Pu via Kuroshio transport, while the lowest inventories of239+240 Pu and237 Np were found in the NPSG region due to its oligotrophic environment. The237 Np originated from the same source as Pu, and the latitudinal pattern of237 Np was consistent with that of Pu. Station SS (in the marginal sea of the NWP) contained high237 Np/239 Pu atom ratios in the deeper layers of sediment and had a237 Np depth profile opposite that of the239+240 Pu profile, compared to other stations; these differences are mainly attributed to differences in the behaviors of237 Np and239 Pu., (Copyright © 2022 Elsevier Ltd. All rights reserved.)- Published
- 2022
- Full Text
- View/download PDF
49. Optimization of Sample Construction Based on NDVI for Cultivated Land Quality Prediction.
- Author
-
Li C, Wang J, Ge L, Zhou Y, and Zhou S
- Subjects
- Agriculture, Cities, Remote Sensing Technology, Neural Networks, Computer, Support Vector Machine
- Abstract
The integrated use of remote sensing technology and machine learning models to evaluate cultivated land quality (CLQ) quickly and efficiently is vital for protecting these lands. The effectiveness of machine-learning methods can be profoundly influenced by training samples. However, in the existing research, samples have mainly been constructed by random point (RPO). Little attention has been devoted to the optimization of sample construction, which may affect the accuracy of evaluation results. In this study, we present two optimization methods for sample construction of random patch (RPA) and area sequence patch (ASP). Differing from RPO samples, it aims to include cultivated land area and its size into sample construction. Based on landsat-8 Operational Land Manager images and agricultural land grading data, the proposed sample construction methods were applied to the machine learning model to predict the CLQ in Dongtai City, Jiangsu Province, China. Four machine learning models (the backpropagation neural network, decision tree, random forest (RF), and support vector machine) were compared based on RPO samples to determine the accurate evaluation model. The best machine learning model was selected to compare RPA and ASP samples with RPO samples. Results determined that the RF model generated the highest accuracy. Meanwhile, a high correlation was noted between the cultivated land area and CLQ. Thus, incorporating cultivated land area in the sample construction attributes can improve the prediction accuracy of the model. Among the three sample construction methods, the ASP yielded the highest prediction accuracy, indicating that the use of a large, cultivated land patch as the sample unit can further elevate the model performance. This study provides a new sample construction method for predicting CLQ using a machine learning model, as well as providing a reference for related research.
- Published
- 2022
- Full Text
- View/download PDF
50. Implications of land sparing and sharing for maintaining regional ecosystem services: An empirical study from a suitable area for agricultural production in China.
- Author
-
Zhang X, Jin X, Liang X, Ren J, Han B, Liu J, Fan Y, and Zhou Y
- Subjects
- Agriculture, China, Sustainable Development, Conservation of Natural Resources, Ecosystem
- Abstract
The clarification of land use management in areas of potential land use conflict plays an important role in maintaining ecosystem services. However, the relationship between land use strategies and ecosystem services in potential conflict zones remains uncertain, lacking quantitative evidence. Therefore, to construct a healthy territorial space system, a spatial classification model for land use was built based on land sparing and sharing. In addition, the inherent characteristics of different modes in the landscape structure and functional heterogeneity were also resolved. Then, an empirical analysis was carried out with the coastal agricultural production area of Maoming City, Guangdong Province. Focusing on the potential area of land use conflicts in Maoming City, that is, the suitable area for agricultural production, this study determined the differences in ecosystem services under multiple land use patterns at the pixel level, explored the trade-offs of ecosystem services in the entire suitable area and a single model, and examined the gradient effect of ecosystem services with the intensity of cultivated land use. According to the results, ecosystem services significantly differed in land use patterns, and the comprehensive ecosystem service was the highest in the land sharing model. Ecosystem services exert a synergistic effect in the entire suitable area for agricultural production, whereas there exists no correlation within a single model. When the arable land area of intensive agriculture exceeds 84.84%, food supply and other ecosystem services will be reduced to varying degrees. The study bridges the gap in research on the relationship between land sparing and sharing and ecosystem services in Chinese regions, and proposes clear land remediation strategies in potential conflict zones, which can thus provide some guidance for achieving sustainable regional development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.