Loading...
Isotopic compositions of lipid biomarker compounds in estuarine plants and surface sediments
Canuel, Elizabeth A. Freeman, Katherine H. Wakeham, Stuart G.
Canuel, Elizabeth A.
Freeman, Katherine H.
Wakeham, Stuart G.
Abstract
We examined the isotopic compositions of fatty acids, sterols, and hydrocarbons isolated from three coastal macrophytes (Zostera marina, Spartina alterniflora, and Juncus roemerianus) in order to investigate the relative contribution of these vascular plants as sources of organic matter in coastal sediments such as Cape Lookout Eight, North Carolina. On average, lipid biomarker compounds extracted from the plants were depleted in C-13 by 3-5 parts per thousand relative to delta(13)C total organic carbon (TOC). However, individual compounds within each lipid class varied by up to 5.6 parts per thousand. Trends in the isotopic compositions of lipids were consistent with delta(13)C(TOC); compounds obtained from Z. marina were the most enriched in C-13 and those from J. roemerianus were the most depleted. The range in isotopic abundances and molecular compositions of the sediments was greater than that obtained from the plants, indicating that additional, presently unidentified sources of organic matter contribute to the Cape Lookout Eight sediments. Similarity between the signatures for suspended particulate matter and the sediments indicates that much of the sedimentary organic matter is derived from algal and bacterial sources. Bacterial sources of organic matter are Likely greater during summer/early fall, and incorporation of C-13-enriched bacterial biomass may contribute to observed seasonal shifts in delta(13)C(TOC) in the surficial sediments.
Description
Date
1997
Journal Title
Journal ISSN
Volume Title
Publisher
Collections
Download Dataset
Files
Loading...
lo.1997.42.7.1570.pdf
Adobe PDF, 2.12 MB
Rights Holder
Usage License
Embargo
Research Projects
Organizational Units
Journal Issue
Keywords
Citation
Advisor
Department
Virginia Institute of Marine Science