High-resolution mass spectrometric characterization of dissolved organic matter from warm and cold periods in the NEEM ice core

作     者：Jian Zhong Xu Amanda Grannas Cun De Xiao Zhi Heng Du Amanda Willoughby Patrick Hatcher Yan Qing An 

作者机构：State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Department of Chemistry Villanova University Department of Chemistry and Biochemistry Old Dominion University 

出 版 物：《Research in Cold and Arid Regions》 (寒旱区科学（英文版）)

年 卷 期：2018年第10卷第1期

页      面：38-46页

核心收录：

学科分类：07[理学] 

基　　金：supported by grants from the Hundred Talents Program of the Chinese Academy of Sciences,the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(NSFC)(41425003,41121001) the Ministry of Science and Technology of China(Mo ST,2013CBA01804) the Scientific Research Foundation of the Key Laboratory of Cryospheric Sciences(SKLCS-ZZ-2017-01) 

主　　题：NEEM ice core FT-ICR-MS dissolved organic matter 

摘      要：Dissolved organic matter(DOM) is an important component of ice cores but is currently poorly characterized. DOM from one Holocene sample(HS, aged at 1600–4500 B.P.) and one Last Glacial Maximum sample(LS, aged at 21000–25000 B.P.) from the North Greenland Eemian Ice Drilling(NEEM) ice core were analyzed by ultra-high resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS). CHO compounds contributed 50% of the compounds identified in negative-ionization mode in these two samples, with significant contributions from organic N, S, and P compounds, likely suggesting that marine DOM was an important source in these samples. Overall, the chemical compositions are similar between these two samples, suggesting their consistent DOM sources. However, subtle differences in the DOM between these two samples are apparent and could indicate differences in source strength or chemistry occurring through both pre-and post-depositional processes. For example, higher relative amounts of condensed carbon compounds in the HS DOM(5%), compared to the LS DOM(2%), suggest potentially important contributions from terrestrial sources. Greater incorporation of P in the observed DOM in the LS DOM(22%), compared to the HS DOM(13%), indicate more active microbiological processes that likely contribute to phosphorus incorporation into the DOM pool. Although these two samples present only a preliminary analysis of DOM in glacial/interglacial periods, the data indicate a need to expand the analysis into a broader range of ice-core samples, geographical locations, and glacial/interglacial periods.