TY - JOUR
T1 - Insoluble prokaryotic membrane lipids in a Sphagnum peat
T2 - Implications for organic matter preservation
AU - Chaves Torres, Lidia
AU - Pancost, Richard D.
PY - 2016/3/1
Y1 - 2016/3/1
N2 - Preservation of organic matter (OM) in the geosphere has a direct impact on carbon bioavailability, the carbon cycle and the formation of fossil fuels. We have examined some of the processes that lead to the preservation of OM by characterising insoluble OM in a Sphagnum peat bog. We focussed on the partitioning of prokaryotic biomarkers between solvent-extractable and insoluble OM fractions and how that partitioning changed with depth. The insoluble organic matter (IOM) was examined using stepwise chemical degradation involving base and acid hydrolysis. Iso- and anteiso-C15 and C17 fatty acids (FAs), hopanoic acid and bishomohopanol, and branched glycerol dialkyl glycerol tetraethers (GDGTs) - diagnostic for Bacteria - were targeted as well as archaeol and isoprenoidal GDGTs - diagnostic for Archaea. High percentages of these compounds - up to 65% - occur in IOM pools, indicating that archaeal- and bacterially derived OM is prone to insolubilization even in shallow sediments (
AB - Preservation of organic matter (OM) in the geosphere has a direct impact on carbon bioavailability, the carbon cycle and the formation of fossil fuels. We have examined some of the processes that lead to the preservation of OM by characterising insoluble OM in a Sphagnum peat bog. We focussed on the partitioning of prokaryotic biomarkers between solvent-extractable and insoluble OM fractions and how that partitioning changed with depth. The insoluble organic matter (IOM) was examined using stepwise chemical degradation involving base and acid hydrolysis. Iso- and anteiso-C15 and C17 fatty acids (FAs), hopanoic acid and bishomohopanol, and branched glycerol dialkyl glycerol tetraethers (GDGTs) - diagnostic for Bacteria - were targeted as well as archaeol and isoprenoidal GDGTs - diagnostic for Archaea. High percentages of these compounds - up to 65% - occur in IOM pools, indicating that archaeal- and bacterially derived OM is prone to insolubilization even in shallow sediments (
KW - Archaeol
KW - Branched fatty acids
KW - Early diagenesis
KW - GDGTs
KW - Selective chemical degradation
UR - http://www.scopus.com/inward/record.url?scp=84956713187&partnerID=8YFLogxK
U2 - 10.1016/j.orggeochem.2015.12.013
DO - 10.1016/j.orggeochem.2015.12.013
M3 - Article (Academic Journal)
AN - SCOPUS:84956713187
SN - 0146-6380
VL - 93
SP - 77
EP - 91
JO - Organic Geochemistry
JF - Organic Geochemistry
ER -