气候变化领域集成服务门户(CCPortal): Lipid composition, caloric content, and novel oxidation products from microbial communities within seasonal pack ice cores

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DOI	10.1016/j.gca.2024.01.003
	Lipid composition, caloric content, and novel oxidation products from microbial communities within seasonal pack ice cores
	Holm, Henry C.; Fredricks, Helen F.; Bent, Shavonna M.; Lowenstein, Daniel P.; Schrage, Kharis R.; Van Mooy, Benjamin A. S.
发表日期	2024
ISSN	0016-7037
EISSN	1872-9533
起始页码	368
卷号	368
英文摘要	Sea ice is a critical feature of polar environments with importance for coastal ecosystems. Along the West Antarctic Peninsula (WAP), climate change is causing decreases in seasonal sea ice duration and extent. Organic carbon within sea ice is an important aspect of southern ocean carbon cycling but less studied than water column or sedimentary carbon reservoirs. Though conditions within sea ice can be extreme, phytoplankton are able to flourish and serve as a key food source for higher trophic levels, especially in the spring and fall. A portion of this sea ice phytoplankton biomass is composed of lipids, which are both calorically dense and useful as tracers of biological processes within the sea ice. To better understand both the trophic value and the diversity of lipids present within sea ice we employed high -resolution accurate -mass mass spectrometry to analyze ice core samples from six sites collected along the peninsula in November 2018. Using untargeted methods we annotated 1,173 intact lipid species across 14 classes of intact polar lipids, triacylglycerols, and pigments. We compared lipids' physical distribution within sea ice cores and found they are highly geographically and physically heterogenous within sites. Ratios between intact polar lipid classes show little signs of phytoplankton nutrient stress; a finding consistent with internally nutrient replete sea ice brines. We found key differences in the composition between pack ice versus fast ice and observed chlorophyll a to be inconsistently correlated with triacylglycerol content. We determined the mean caloric content of lipids within pack ice (4.45 +/- 3.47 kJ m-2) and found that caloric densities from the lipids alone were in the range of total water column energy content. Lastly, we show evidence of fatty acid hydroxy fatty acid triacylglycerols within the ice matrix and discuss possible biochemical sources of these novel biomarkers in an ocean system. These results shed light on the chemical diversity of a dynamic and ecosystem relevant carbon pool.
英文关键词	Sea Ice; Lipidomics; FAHFA-TAG; Antarctica; Algae
语种	英语
WOS研究方向	Geochemistry & Geophysics
WOS类目	Geochemistry & Geophysics
WOS记录号	WOS:001171457300001
来源期刊	GEOCHIMICA ET COSMOCHIMICA ACTA
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/304725
作者单位	Woods Hole Oceanographic Institution; Massachusetts Institute of Technology (MIT)
推荐引用方式 GB/T 7714	Holm, Henry C.,Fredricks, Helen F.,Bent, Shavonna M.,et al. Lipid composition, caloric content, and novel oxidation products from microbial communities within seasonal pack ice cores[J],2024,368.
APA	Holm, Henry C.,Fredricks, Helen F.,Bent, Shavonna M.,Lowenstein, Daniel P.,Schrage, Kharis R.,&Van Mooy, Benjamin A. S..(2024).Lipid composition, caloric content, and novel oxidation products from microbial communities within seasonal pack ice cores.GEOCHIMICA ET COSMOCHIMICA ACTA,368.
MLA	Holm, Henry C.,et al."Lipid composition, caloric content, and novel oxidation products from microbial communities within seasonal pack ice cores".GEOCHIMICA ET COSMOCHIMICA ACTA 368(2024).