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Ice retreat in Wilkes Basin of East Antarctica during a warm interglacial 期刊论文
NATURE, 2020, 583 (7817) : 554-+
作者:  T. Blackburn;  G. H. Edwards;  S. Tulaczyk;  M. Scudder;  G. Piccione;  B. Hallet;  N. McLean;  J. C. Zachos;  B. Cheney;  J. T. Babbe
收藏  |  浏览/下载:21/0  |  提交时间:2020/08/09

Uranium isotopes in subglacial precipitates from the Wilkes Basin of the East Antarctic Ice Sheet reveal ice retreat during a warm Pleistocene interglacial period about 400,000 years ago.


Efforts to improve sea level forecasting on a warming planet have focused on determining the temperature, sea level and extent of polar ice sheets during Earth'  s past interglacial warm periods(1-3). About 400,000 years ago, during the interglacial period known as Marine Isotopic Stage 11 (MIS11), the global temperature was 1 to 2 degrees Celsius greater(2)and sea level was 6 to 13 metres higher(1,3). Sea level estimates in excess of about 10 metres, however, have been discounted because these require a contribution from the East Antarctic Ice Sheet(3), which has been argued to have remained stable for millions of years before and includes MIS11(4,5). Here we show how the evolution of(234)U enrichment within the subglacial waters of East Antarctica recorded the ice sheet'  s response to MIS11 warming. Within the Wilkes Basin, subglacial chemical precipitates of opal and calcite record accumulation of(234)U (the product of rock-water contact within an isolated subglacial reservoir) up to 20 times higher than that found in marine waters. The timescales of(234)U enrichment place the inception of this reservoir at MIS11. Informed by the(234)U cycling observed in the Laurentide Ice Sheet, where(234)U accumulated during periods of ice stability(6)and was flushed to global oceans in response to deglaciation(7), we interpret our East Antarctic dataset to represent ice loss within the Wilkes Basin at MIS11. The(234)U accumulation within the Wilkes Basin is also observed in the McMurdo Dry Valleys brines(8-10), indicating(11)that the brine originated beneath the adjacent East Antarctic Ice Sheet. The marine origin of brine salts(10)and bacteria(12)implies that MIS11 ice loss was coupled with marine flooding. Collectively, these data indicate that during one of the warmest Pleistocene interglacials, the ice sheet margin at the Wilkes Basin retreated to near the precipitate location, about 700 kilometres inland from the current position of the ice margin, which-assuming current ice volumes-would have contributed about 3 to 4 metres(13)to global sea levels.


  
Substrate regulation leads to differential responses of microbial ammonia-oxidizing communities to ocean warming 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Zheng, Zhen-Zhen;  Zheng, Li-Wei;  Xu, Min Nina;  Tan, Ehui;  Hutchins, David A.;  Deng, Wenchao;  Zhang, Yao;  Shi, Dalin;  Dai, Minhan;  Kao, Shuh-Ji
收藏  |  浏览/下载:12/0  |  提交时间:2020/07/21
Airborne bacteria confirm the pristine nature of the Southern Ocean boundary layer 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (24) : 13275-13282
作者:  Uetake, Jun;  Hill, Thomas C. J.;  Moore, Kathryn A.;  DeMott, Paul J.;  Protat, Alain;  Kreidenweis, Sonia M.
收藏  |  浏览/下载:17/0  |  提交时间:2020/06/09
bioaerosol  marine aerosol  Southern Ocean  
Accumulation of ambient phosphate into the periplasm of marine bacteria is proton motive force dependent 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Kamennaya, Nina A.;  Geraki, Kalotina;  Scanlan, David J.;  Zubkov, Mikhail, V
收藏  |  浏览/下载:9/0  |  提交时间:2020/06/01
Ediacaran reorganization of the marine phosphorus cycle 期刊论文
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2020, 117 (22) : 11961-11967
作者:  Laakso, Thomas A.;  Sperling, Erik A.;  Johnston, David T.;  Knoll, Andrew H.
收藏  |  浏览/下载:9/0  |  提交时间:2020/05/20
Ediacaran  biosphere  sulfate  phopshorus  phosphorite  
Extracellular electron transfer-dependent anaerobic oxidation of ammonium by anammox bacteria 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Shaw, Dario R.;  Ali, Muhammad;  Katuri, Krishna P.;  Gralnick, Jeffrey A.;  Reimann, Joachim;  Mesman, Rob;  van Niftrik, Laura;  Jetten, Mike S. M.;  Saikaly, Pascal E.
收藏  |  浏览/下载:7/0  |  提交时间:2020/05/13
Single-cell bacterial transcription measurements reveal the importance of dimethylsulfoniopropionate (DMSP) hotspots in ocean sulfur cycling 期刊论文
NATURE COMMUNICATIONS, 2020, 11 (1)
作者:  Gao, Cherry;  Fernandez, Vicente I.;  Lee, Kang Soo;  Fenizia, Simona;  Pohnert, Georg;  Seymour, Justin R.;  Raina, Jean-Baptiste;  Stocker, Roman
收藏  |  浏览/下载:6/0  |  提交时间:2020/05/13
Warming stimulates sediment denitrification at the expense of anaerobic ammonium oxidation 期刊论文
NATURE CLIMATE CHANGE, 2020, 10 (4) : 349-+
作者:  Tan, Ehui;  Zou, Wenbin;  Zheng, Zhenzhen;  Yan, Xiuli;  Du, Moge;  Hsu, Ting-Chang;  Tian, Li;  Middelburg, Jack J.;  Trull, Thomas W.;  Kao, Shuh-ji
收藏  |  浏览/下载:7/0  |  提交时间:2020/05/13
Recycling and metabolic flexibility dictate life in the lower oceanic crust 期刊论文
NATURE, 2020, 579 (7798) : 250-+
作者:  Zhou, Peng;  Yang, Xing-Lou;  Wang, Xian-Guang;  Hu, Ben;  Zhang, Lei;  Zhang, Wei;  Si, Hao-Rui;  Zhu, Yan;  Li, Bei;  Huang, Chao-Lin;  Chen, Hui-Dong;  Chen, Jing;  Luo, Yun;  Guo, Hua;  Jiang, Ren-Di;  Liu, Mei-Qin;  Chen, Ying;  Shen, Xu-Rui;  Wang, Xi;  Zheng, Xiao-Shuang;  Zhao, Kai;  Chen, Quan-Jiao;  Deng, Fei;  Liu, Lin-Lin;  Yan, Bing;  Zhan, Fa-Xian;  Wang, Yan-Yi;  Xiao, Geng-Fu;  Shi, Zheng-Li
收藏  |  浏览/下载:37/0  |  提交时间:2020/05/13

The lithified lower oceanic crust is one of Earth'  s last biological frontiers as it is difficult to access. It is challenging for microbiota that live in marine subsurface sediments or igneous basement to obtain sufficient carbon resources and energy to support growth(1-3) or to meet basal power requirements(4) during periods of resource scarcity. Here we show how limited and unpredictable sources of carbon and energy dictate survival strategies used by low-biomass microbial communities that live 10-750 m below the seafloor at Atlantis Bank, Indian Ocean, where Earth'  s lower crust is exposed at the seafloor. Assays of enzyme activities, lipid biomarkers, marker genes and microscopy indicate heterogeneously distributed and viable biomass with ultralow cell densities (fewer than 2,000 cells per cm(3)). Expression of genes involved in unexpected heterotrophic processes includes those with a role in the degradation of polyaromatic hydrocarbons, use of polyhydroxyalkanoates as carbon-storage molecules and recycling of amino acids to produce compounds that can participate in redox reactions and energy production. Our study provides insights into how microorganisms in the plutonic crust are able to survive within fractures or porous substrates by coupling sources of energy to organic and inorganic carbon resources that are probably delivered through the circulation of subseafloor fluids or seawater.


  
Formation Criteria for Hyporheic Anoxic Microzones: Assessing Interactions of Hydraulics, Nutrients, and Biofilms 期刊论文
WATER RESOURCES RESEARCH, 2020, 56 (3)
作者:  Chowdhury, Sinchan Roy;  Zarnetske, Jay P.;  Phanikumar, Mantha S.;  Briggs, Martin A.;  Day-Lewis, Frederick;  Singha, Kamini
收藏  |  浏览/下载:7/0  |  提交时间:2020/07/02