Long-term preservation of biomolecules in lake sediments: potential importance of physical shielding by recalcitrant cell walls
OPEN ACCESS
Loading...
Author / Producer
Date
2022-07
Publication Type
Journal Article
ETH Bibliography
yes
Citations
Altmetric
OPEN ACCESS
Data
Rights / License
Abstract
Even though lake sediments are globally important organic carbon (OC) sinks, the controls on long-term OC storage in these sediments are unclear. Using a multiproxy approach, we investigate changes in diatom, green algae, and vascular plant biomolecules in sedimentary records from the past centuries across five temperate lakes with different trophic histories. Despite past increases in the input and burial of OC in sediments of eutrophic lakes, biomolecule quantities in sediments of all lakes are primarily controlled by postburial microbial degradation over the time scales studied. We, moreover, observe major differences in biomolecule degradation patterns across diatoms, green algae, and vascular plants. Degradation rates of labile diatom DNA exceed those of chemically more resistant diatom lipids, suggesting that chemical reactivity mainly controls diatom biomolecule degradation rates in the lakes studied. By contrast, degradation rates of green algal and vascular plant DNA are significantly lower than those of diatom DNA, and in a similar range as corresponding, much less reactive lipid biomarkers and structural macromolecules, including lignin. We propose that physical shielding by degradation-resistant cell wall components, such as algaenan in green algae and lignin in vascular plants, contributes to the long-term preservation of labile biomolecules in both groups and significantly influences the long-term burial of OC in lake sediments.
Permanent link
Publication status
published
External links
Editor
Book title
Journal / series
Volume
1 (3)
Pages / Article No.
Publisher
Oxford University Press
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
lake sediments; biomolecules; DNA; long-term preservation; physical shielding
Organisational unit
03933 - Winkel, Lenny / Winkel, Lenny
09496 - Lever, Mark A. (ehemalig) / Lever, Mark A. (former)
Notes
Funding
163371 - Role of Bioturbation in Controlling Microbial Community Composition and Biogeochemical Cycles in Marine and Lacustrine Sediments (SNF)