File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Salinity-controlled isomerization of lacustrine brGDGTs impacts the associated MBT5ME' terrestrial temperature index

TitleSalinity-controlled isomerization of lacustrine brGDGTs impacts the associated MBT5ME' terrestrial temperature index
Authors
KeywordsbrGDGTs
Temperature
Salinity
MBT'5ME
Isomerization
Issue Date2021
PublisherPergamon. The Journal's web site is located at http://www.elsevier.com/locate/gca
Citation
Geochimica et Cosmochimica Acta, 2021, v. 305, p. 33-48 How to Cite?
AbstractBranched glycerol dialkyl glycerol tetraethers (brGDGTs) are microbial molecular fossils ubiquitous in natural environments. The correlation between the Methylation Index of brGDGTs (the MBT'5ME paleothermometer) and temperature offers an important tool for reconstructing past terrestrial temperatures. However, factors other than temperature could also affect the distribution of brGDGTs in lacustrine systems, hampering the quantitative application of this paleothermometer. Here we investigated brGDGT distributions in contemporary sediments collected from 52 lakes in mid-latitude Asia. Combined with published brGDGT data from other lakes across the globe, we have found a strong salinity control on the relative abundance of 5-methyl brGDGTs versus their late-eluting isomers (including 6-methyl, 7-methyl, and unknown isomers). This allows the development of novel indices based on the isomerization of brGDGTs for tracing past lake water salinity. We also demonstrate that salinity-controlled isomerization of pentamethylated and hexamethylated brGDGTs can significantly impact the MBT'5ME paleothermometer, potentially leading to an overestimation of past temperature, but the temperature signal can be extracted out of the MBT'5ME index after correcting the salinity effect. As demonstrated in application to a Lake Qinghai (China) sediment core spanning the last 18 kyr, our finding could facilitate the simultaneous retrieval of reliable temperature and salinity records using brGDGTs in lacustrine settings, in particular for lakes that have experienced large salinity changes during the geological past.
Persistent Identifierhttp://hdl.handle.net/10722/304964
ISSN
2023 Impact Factor: 4.5
2023 SCImago Journal Rankings: 2.278
ISI Accession Number ID

 

DC FieldValueLanguage
dc.contributor.authorWang, H-
dc.contributor.authorLiu, W-
dc.contributor.authorHe, Y-
dc.contributor.authorZhou, A-
dc.contributor.authorZhao, H-
dc.contributor.authorLiu, H-
dc.contributor.authorCao, Y-
dc.contributor.authorHu, J-
dc.contributor.authorMeng, B-
dc.contributor.authorJiang, J-
dc.contributor.authorKolpakova, M-
dc.contributor.authorKrivonogov, S-
dc.contributor.authorLiu, Z-
dc.date.accessioned2021-10-05T02:37:46Z-
dc.date.available2021-10-05T02:37:46Z-
dc.date.issued2021-
dc.identifier.citationGeochimica et Cosmochimica Acta, 2021, v. 305, p. 33-48-
dc.identifier.issn0016-7037-
dc.identifier.urihttp://hdl.handle.net/10722/304964-
dc.description.abstractBranched glycerol dialkyl glycerol tetraethers (brGDGTs) are microbial molecular fossils ubiquitous in natural environments. The correlation between the Methylation Index of brGDGTs (the MBT'5ME paleothermometer) and temperature offers an important tool for reconstructing past terrestrial temperatures. However, factors other than temperature could also affect the distribution of brGDGTs in lacustrine systems, hampering the quantitative application of this paleothermometer. Here we investigated brGDGT distributions in contemporary sediments collected from 52 lakes in mid-latitude Asia. Combined with published brGDGT data from other lakes across the globe, we have found a strong salinity control on the relative abundance of 5-methyl brGDGTs versus their late-eluting isomers (including 6-methyl, 7-methyl, and unknown isomers). This allows the development of novel indices based on the isomerization of brGDGTs for tracing past lake water salinity. We also demonstrate that salinity-controlled isomerization of pentamethylated and hexamethylated brGDGTs can significantly impact the MBT'5ME paleothermometer, potentially leading to an overestimation of past temperature, but the temperature signal can be extracted out of the MBT'5ME index after correcting the salinity effect. As demonstrated in application to a Lake Qinghai (China) sediment core spanning the last 18 kyr, our finding could facilitate the simultaneous retrieval of reliable temperature and salinity records using brGDGTs in lacustrine settings, in particular for lakes that have experienced large salinity changes during the geological past.-
dc.languageeng-
dc.publisherPergamon. The Journal's web site is located at http://www.elsevier.com/locate/gca-
dc.relation.ispartofGeochimica et Cosmochimica Acta-
dc.subjectbrGDGTs-
dc.subjectTemperature-
dc.subjectSalinity-
dc.subjectMBT'5ME-
dc.subjectIsomerization-
dc.titleSalinity-controlled isomerization of lacustrine brGDGTs impacts the associated MBT5ME' terrestrial temperature index-
dc.typeArticle-
dc.identifier.emailLiu, Z: zhliu@hku.hk-
dc.identifier.authorityLiu, Z=rp00750-
dc.description.naturelink_to_subscribed_fulltext-
dc.identifier.doi10.1016/j.gca.2021.05.004-
dc.identifier.scopuseid_2-s2.0-85110414681-
dc.identifier.hkuros326263-
dc.identifier.volume305-
dc.identifier.spage33-
dc.identifier.epage48-
dc.identifier.isiWOS:000660120900003-
dc.publisher.placeUnited Kingdom-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats