Environmental controls on long-chain alkenone occurrence and compositional patterns in lacustrine sediments, northwestern China

doi:10.1016/j.orggeochem.2015.10.009

	Environmental controls on long-chain alkenone occurrence and compositional patterns in lacustrine sediments, northwestern China
	Song, Mu 2; Liu, Zhonghui 2; Liu, Weiguo 1; Zhao, Yan 5; Wu, Jinglu 3; Zhao, Cheng 2,3; He, Yuxin 2,4; Zhou, Aifeng 5
刊名	ORGANIC GEOCHEMISTRY
	2016
卷号	91 期号:2016 页码:43-53
关键词	Alkenones Salinity Temperature Lacustrine Settings Northwestern China Lakes
DOI	10.1016/j.orggeochem.2015.10.009
文献子类	Article
英文摘要	Long chain alkenones occur widely in lacustrine settings and their compositions are potential proxies for reconstructing terrestrial paleoclimatological and paleoenvironmental changes. However, factors influencing their occurrence, abundance, compositional pattern and unsaturation indices are not well understood. Here we investigated the alkenones in surface sediments from 19 lakes in northwestern China as well as potential environmental factors. Of the lakes, 12 contain long chain alkenones, 3 have the isomeric C-37:3 alkenone and 3 have very low abundance of alkenones. Our results show that salinity has a substantial influence on the occurrence, concentration and compositional pattern. Most of the compositions are dominated by tri-unsaturated compounds, with C-38 methyl ketones absent. The predominance of C-37:4 and the occurrence of a C-37:3 isomer are suggested to be responses to low salinity as both are only found in the three alkenone-containing freshwater lakes. The proportion of C-37:4 varies by up to 50% and shows a negative relationship with salinity within the surveyed region. An arched relationship of alkenone content and salinity is apparent, with no or very low contents of alkenones in freshwater (salinity < 3 g/L) and hypersaline (> 100 g/L) environments. The U-37(K') index is suggested to be a better terrestrial temperature proxy than U-37(K) as U-37(K') values from lakes containing elevated alkenone content are all within the ranges of published U-37(K')-temperature calibrations, and U-37(K) values show a weak positive relationship with salinity. (C) 2015 Elsevier Ltd. All rights reserved.
WOS关键词	HAPTOPHYTE EMILIANIA-HUXLEYI ; NORTHERN TIBETAN PLATEAU ; GEPHYROCAPSA-OCEANICA ; LAKE-SEDIMENTS ; UNSATURATION RATIO ; GROWTH TEMPERATURE ; MICROBIAL MATS ; ACE LAKE ; DISTRIBUTIONS ; DEGRADATION
WOS研究方向	Geochemistry & Geophysics
语种	英语
WOS记录号	WOS:000366706100005
内容类型	期刊论文
源URL	[http://ir.ieecas.cn/handle/361006/5863]
专题	地球环境研究所_加速器质谱中心
作者单位	1.Chinese Acad Sci, IEE, State Key Lab Loess & Quaternary Geol, Xian 0075, Peoples R China 2.Univ Hong Kong, Dept Earth Sci, Hong Kong, Hong Kong, Peoples R China 3.Chinese Acad Sci, Nanjing Inst Geog & Limnol, State Key Lab Lake Sci & Environm, Nanjing 210008, Jiangsu, Peoples R China 4.Zhejiang Univ, Dept Earth Sci, Hangzhou 310058, Zhejiang, Peoples R China 5.Lanzhou Univ, Coll Earth & Environm Sci, Minist Educ, Key Lab Western Chinas Environm Syst, Lanzhou 730000, Peoples R China
推荐引用方式 GB/T 7714	Song, Mu,Liu, Zhonghui,Liu, Weiguo,et al. Environmental controls on long-chain alkenone occurrence and compositional patterns in lacustrine sediments, northwestern China[J]. ORGANIC GEOCHEMISTRY,2016,91(2016):43-53.
APA	Song, Mu.,Liu, Zhonghui.,Liu, Weiguo.,Zhao, Yan.,Wu, Jinglu.,...&Zhou, Aifeng.(2016).Environmental controls on long-chain alkenone occurrence and compositional patterns in lacustrine sediments, northwestern China.ORGANIC GEOCHEMISTRY,91(2016),43-53.
MLA	Song, Mu,et al."Environmental controls on long-chain alkenone occurrence and compositional patterns in lacustrine sediments, northwestern China".ORGANIC GEOCHEMISTRY 91.2016(2016):43-53.