Depth-related differences in archaeal populations impact the isoprenoid tetraether lipid composition of the Mediterranean Sea water column

被引：32

作者：

Besseling, Marc A. ^{[1
,2
]}

Hopmans, Ellen C. ^{[1
,2
]}

Koenen, Michel ^{[1
,2
]}

van der Meer, Marcel T. J. ^{[1
,2
]}

Vreugdenhil, Sanne ^{[1
,2
]}

Schouten, Stefan ^{[1
,2
,3
]}

Damste, Jaap S. Sinninghe ^{[1
,2
,3
]}

Villanueva, Laura ^{[1
,2
]}

机构：

[1] NIOZ Royal Netherlands Inst Sea Res, Dept Marine Microbiol & Biogeochem, POB 59, NL-1790 AB Den Burg, Netherlands

[2] Univ Utrecht, POB 59, NL-1790 AB Den Burg, Netherlands

[3] Univ Utrecht, Fac Geosci, Dept Earth Sci, POB 80-021, NL-3508 TA Utrecht, Netherlands

来源：

ORGANIC GEOCHEMISTRY | 2019年 / 135卷

基金：

欧洲研究理事会;

关键词：

Archaea; Thaumarchaeota; Marine Euryarchaeota group II; Isoprenoid GDGTs; TEX86; Paleothermometer; Mediterranean Sea; AMMONIA-OXIDIZING ARCHAEA; MEMBRANE-LIPIDS; INTACT POLAR; NITROSOPUMILUS-MARITIMUS; PLANKTONIC CRENARCHAEOTA; GDGT DISTRIBUTIONS; SURFACE SEDIMENTS; MARINE; BACTERIA; CORE;

D O I：

10.1016/j.orggeochem.2019.06.008

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

Thaumarchaeota are one of the most abundant groups of Archaea in the marine water column. Their membrane consists of isoprenoid glycerol dibiphytanyl glycerol tetraethers (GDGTs) which are applied in the widely used TEX86 proxy to reconstruct past sea surface temperatures (SSTs). However, in some specific marine systems, such as the Mediterranean Sea, core-top TEX86-derived temperatures do not seem to reflect annual mean SSTs. This has been attributed to contributions of deep-water dwelling Thaumarchaeota. Here, we investigate the potential causes of this bias by studying both the archaeal diversity as well as the intact polar lipid (IPL) GDGT composition in the Mediterranean water column by a combined 16S rRNA gene amplicon sequencing and a lipidomic approach on suspended particulate matter (SPM) at different water depths. The archaeal distribution showed a dominance of archaea other than Thaumarchaeota, i.e. Marine Euryarchaeota group II and III in the upper epipelagic waters (0-100 m deep), while Thaumarchaeota (Marine group I; MGI) dominated the subsurface and the deeper waters. This shift in the archaeal community composition coincided with a decrease in IPL GDGT-0 and increase of IPL crenarchaeol. The ratio of GDGT-2/GDGT-3 increased with water depth, but values were lower than observed in deep marine waters of some other regions. The increase of the GDGT-2/GDGT-3 ratio coincided with the high relative abundance of deep-water MGI, which may be linked to the high temperature and salinity found in specific water masses of the Mediterranean Sea. We conclude that these particularities of the Mediterranean Sea are responsible for the overestimated SST based on TEX86. (C) 2019 The Authors. Published by Elsevier Ltd.

引用

页码：16 / 31

页数：16