More reducing bottom-water redox conditions during the Last Glacial Maximum in the southern Challenger Deep (Mariana Trench, western Pacific) driven by enhanced productivity

doi:10.1016/j.dsr2.2017.01.006

CORC > 自然资源部第一海洋研究所 > 自然资源部第一海洋研究所 > 业务部门 > 海洋地质与地球物理研究室

	More reducing bottom-water redox conditions during the Last Glacial Maximum in the southern Challenger Deep (Mariana Trench, western Pacific) driven by enhanced productivity
	Luo, Min 1; Algeo, Thomas J.2; Tong, Hongpeng 3; Gieskes, Joris 4; Chen, Linying 1; Shi, Xuefa 5,6; Chen, Duofu 1
刊名	Deep-Sea Research Part II: Topical Studies in Oceanography
	2017
卷号	155 页码:70-82
关键词	Binary alloys Blooms (metal) Carbon dioxide Geographical regions Glacial geology Iron alloys Iron compounds Manganese alloys Manganese compounds Manganese removal (water treatment) Phosphate minerals Photosynthesis Phytoplankton Rare earth elements Rare earths Trace elements
ISSN号	09670645
DOI	10.1016/j.dsr2.2017.01.006
英文摘要	The modern southern Mariana Trench is characterized by oligotrophic surface waters, resulting in low primary productivity and well-oxygenated bottom waters. This study investigates changes in the redox conditions of bottom waters in the southern Mariana Trench during the Last Glacial Maximum (LGM) and their potential causes. We measured major, trace, and rare earth elements (REE) in three gravity cores (GC03, GC04, and GC05) and one box core (BC11) retrieved from the southern Challenger Deep at water depths from 5289 to 7118m. The upper sediment layers of both GC05 and BC11 are dominated by valve fragments of the giant diatom Ethmodiscus rex, forming laminated diatom mats (LDMs).14C-AMS dates of bulk organic matter show that the LDMs accumulated between 18.4 and 21.8 kyr B.P., corresponding to the LGM. Modest enrichments of U and Mo along with weak or absent Ce anomalies in the LDM point to suboxic conditions during the LGM. In contrast, non-LDM samples exhibit little to no enrichment of redox-sensitive elements as well as negative Ce anomalies, indicating deposition under oxic bottom-water conditions. The Ce anomalies are considered valid proxies for bottom-water redox conditions because REE signatures were acquired in the early diagenetic environment, as indicated by strong P-REE correlations and middle-REE enrichment associated with early diagenetic cycling of Fe-Mn oxyhydroxides in the sediment column followed by capture of the REE signal by biogenic and/or authigenic apatite. We postulate that the more reducing bottom-water conditions during the LGM were linked to increased primary productivity induced by enhanced Asian dust input. As shown in earlier studies, the increased primary productivity associated with Ethmodiscus rex blooms in the eastern Philippine Sea played a significant role in capturing atmospheric CO2during the LGM. Consequently, the magnitude of atmospheric CO2sequestration by giant diatom blooms during the LGM may have been greater than previously envisaged. © 2017 Elsevier Ltd.
资助项目	Scientific Innovation Program of Shanghai Committee of Science and Technology[14DZ1205500] ; Scientific Innovation Program of Shanghai Committee of Science and Technology[14DZ2250900] ; Scientific Innovation Program of Shanghai Committee of Science and Technology[15DZ1207000]
WOS研究方向	Oceanography
语种	英语
出版者	Elsevier Ltd
WOS记录号	WOS:000454184400010
内容类型	期刊论文
源URL	[http://ir.fio.com.cn/handle/2SI8HI0U/6506]
专题	业务部门_海洋地质与地球物理研究室
作者单位	1.Shanghai Engineering Research Center of Hadal Science and Technology, College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China;; 2.Department of Geology, University of Cincinnati, Cincinnati, OH 45221-0013, USA;; 3.Key Laboratory of Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China;; 4.Scripps Institution of Oceanography, La Jolla, San Diego, CA, USA;; 5.Key Laboratory of Marine Sedimentology and Environmental Geology, First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China;; 6.Function Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061, China
推荐引用方式 GB/T 7714	Luo, Min,Algeo, Thomas J.,Tong, Hongpeng,et al. More reducing bottom-water redox conditions during the Last Glacial Maximum in the southern Challenger Deep (Mariana Trench, western Pacific) driven by enhanced productivity[J]. Deep-Sea Research Part II: Topical Studies in Oceanography,2017,155:70-82.
APA	Luo, Min.,Algeo, Thomas J..,Tong, Hongpeng.,Gieskes, Joris.,Chen, Linying.,...&Chen, Duofu.(2017).More reducing bottom-water redox conditions during the Last Glacial Maximum in the southern Challenger Deep (Mariana Trench, western Pacific) driven by enhanced productivity.Deep-Sea Research Part II: Topical Studies in Oceanography,155,70-82.
MLA	Luo, Min,et al."More reducing bottom-water redox conditions during the Last Glacial Maximum in the southern Challenger Deep (Mariana Trench, western Pacific) driven by enhanced productivity".Deep-Sea Research Part II: Topical Studies in Oceanography 155(2017):70-82.