Characterization of dissolved organic matter (DOM) from glacial environments using total fluorescence spectroscopy and parallel factor analysis
Characterization of dissolved organic matter (DOM) from glacial environments using total fluorescence spectroscopy and parallel factor analysis
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DOI：
10.3189/172756411795931912
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发表时间：
2010-12
影响因子：
2.9
通讯作者：
A. Dubnick;J. Barker;M. Sharp;J. Wadham;G. Lis;J. Telling;S. Fitzsimons;M. Jackson
中科院分区：
文献类型：
--
作者：
A. Dubnick;J. Barker;M. Sharp;J. Wadham;G. Lis;J. Telling;S. Fitzsimons;M. Jackson
摘要水中溶解有机物(DOM)是还原有机碳的主要储存库，对海洋和淡水环境中的异养生物生产力和水质有重要影响。尽管DOM在温带水生和土壤环境中的形态和转化已被广泛研究，但在冰川环境中却并非如此。采用荧光激发-发射矩阵(EEM)、平行因子分析(PARAFAC)和聚类分析等方法，对加拿大北极、挪威和南极7个冰川冰上、冰川、冰下和冰前环境中DOM的荧光成分进行了研究。至少确定了五个显著的荧光DOM组分，它们解释了数据集中98.2%的方差。其中包括四种类蛋白质成分和一种类腐殖质成分。来自这些冰川的DOM的主要蛋白质特征与以前从湖泊、河流、河口和海洋环境中描述的DOM更腐殖化的特征非常不同。来自采样冰川的DOM在性质上大体相似，尽管它们在地理上不同的位置、不同的热制度以及站点间和站点内潜在有机质来源的差异。冰川样品具有较低的类腐殖质：类蛋白质荧光比值，而融水样品具有较高的比值。
Abstract Aquatic dissolved organic matter (DOM) is a major reservoir of reduced organic carbon and has a significant influence on heterotrophic biological productivity and water quality in marine and freshwater environments. Although the forms and transformations of DOM in temperate aquatic and soil environments have been studied extensively, this is not the case for glacial environments. In this study, fluorescent excitation–emission matrices (EEMs), parallel factor analysis (PARAFAC) and cluster analysis were used to characterize the fluorescing components of DOM in ice and water samples from supraglacial, englacial, subglacial and proglacial environments of seven glaciers in the Canadian Arctic, Norway and Antarctica. At least five significant fluorescent DOM fractions were identified, which accounted for 98.2% of the variance in the dataset. These included four protein-like components and one humic-like component. The predominantly proteinaceous character of DOM from these glaciers is very different from the more humic character of DOM described previously from lacustrine, fluvial, estuarine and marine environments. DOM from the sampled glaciers is broadly similar in character despite their geographically distinct locations, different thermal regimes and inter- and intra-site differences in potential organic matter sources. Glacier ice samples had a relatively low ratio of humic-like :protein-like fluorescence while meltwater samples had a higher ratio.