气候变化领域集成服务门户(CCPortal): Biomarker Evidence of Algal-Microbial Community Changes Linked to Redox and Salinity Variation, Upper Devonian Chattanooga Shale (Tennessee, USA)

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DOI	10.1130/B35543.1
	Biomarker Evidence of Algal-Microbial Community Changes Linked to Redox and Salinity Variation, Upper Devonian Chattanooga Shale (Tennessee, USA)
	Song Y.; Gilleaudeau G.J.; Lyons T.J.; Jeffrey Over D.; Lyons T.W.; Anbar A.D.; Xie S.
发表日期	2020
ISSN	167606
起始页码	409
结束页码	424
卷号	133
英文摘要	climate change and widespread oceanic anoxia. Here, we provide high-resolution lipid biomarker chemostrati- graphic records from the Upper Devonian Chattanooga Shale (Tennessee, USA) to investigate algal-microbial community changes in the southern Illinois Basin that were related to contemporaneous shifts in marine redox (as proxied by trace metals, Fe-species, and Corg/P) and salinity conditions (as proxied by B/Ga, Sr/Ba, and S/total organic carbon). The Frasnian was characterized by dominantly bacterial lipids (high hopane/sterane), near-marine salinity, and a shift from oxic to increasingly reducing conditions in response to increasing organic carbon sinking fluxes. Aryl isoprenoids and aryl isoprenoid ratios reveal that the O2-H2S chemocline was unstable and intermittently shallow (i.e., within the photic zone). The Frasnian-Famennian boundary was marked by a shift in micro- algal community composition toward green algal (e.g., prasinophyte) dominance (lower C27 and higher C28 and C29 steranes), a sharp reduction in watermass salinity, and a stable O2-H2S chemocline below the photic zone, conditions that persisted until nearly the end of the Famennian. We infer that changing watermass conditions, especially a sharp reduction in salinity to possibly low-brackish conditions (10 psu), were the primary cause of concurrent changes in the microalgal community, reflecting tolerance of low-salinity conditions by green algae. Transient spikes in moretane/hopane (M/H) ratios may record enhanced terrestrial weathering at the Fras- nian-Famennian and Devonian-Carboniferous boundaries, triggered by coeval glacio- eustatic falls and increased inputs of soil organic matter. High M/H and pristane/phy- tane, in combination with low chemical index of alteration and K/Al, record a decrease in chemical weathering intensity during the Famennian that may have been due to contemporaneous climatic cooling, and a concurrent reduction in silt content may reflect stabilization of land surfaces by vascular plants and resulting reduced sediment yields. This study demonstrates the effectiveness of combining organic and inorganic geochemical proxies (including novel paleosalinity indices) for determination of environmental controls on the composition and productivity of plankton communities in paleomarine systems. ©2020 Geological Society of America
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/184766
作者单位	State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, School of Earth Sciences, Wuhan, 430074, China; Department of Geology, University of Cincinnati, Cincinnati, Ohio 45221-0013, United States; Department of Atmospheric, Oceanic, and Earth Sciences, George Mason University, Fairfax, Virginia 22030, United States; School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287, United States; State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, 430074, China; Department of Geological Sciences, SUNY-Geneseo, Geneseo, New York 14454, United States; Department of Earth and Planetary Sciences, University of California-Riverside, Riverside, California 92521, United States
推荐引用方式 GB/T 7714	Song Y.,Gilleaudeau G.J.,Lyons T.J.,et al. Biomarker Evidence of Algal-Microbial Community Changes Linked to Redox and Salinity Variation, Upper Devonian Chattanooga Shale (Tennessee, USA)[J],2020,133.
APA	Song Y..,Gilleaudeau G.J..,Lyons T.J..,Jeffrey Over D..,Lyons T.W..,...&Xie S..(2020).Biomarker Evidence of Algal-Microbial Community Changes Linked to Redox and Salinity Variation, Upper Devonian Chattanooga Shale (Tennessee, USA).Bulletin of the Geological Society of America,133.
MLA	Song Y.,et al."Biomarker Evidence of Algal-Microbial Community Changes Linked to Redox and Salinity Variation, Upper Devonian Chattanooga Shale (Tennessee, USA)".Bulletin of the Geological Society of America 133(2020).