The Key Laboratory of Water and Sediment Sciences, Ministry of Education, School of Environment, Beijing Normal University, Beijing, P.R. China ; State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, P.R. China.
PLoS One. 2013 Oct 14;8(10):e76633. doi: 10.1371/journal.pone.0076633. eCollection 2013.
Dissolved organic matter (DOM) in sediment pore waters from Yangtze estuary of China based on abundance, UV absorbance, molecular weight distribution and fluorescence were investigated using a combination of various parameters of DOM as well as 3D fluorescence excitation emission matrix spectra (F-EEMS) with the parallel factor and principal component analysis (PARAFAC-PCA). The results indicated that DOM in pore water of Yangtze estuary was very variable which mainly composed of low aromaticity and molecular weight materials. Three humic-like substances (C1, C2, C4) and one protein-like substance (C3) were identified by PARAFAC model. C1, C2 and C4 exhibited same trends and were very similar. The separation of samples on both axes of the PCA showed the difference in DOM properties. C1, C2 and C4 concurrently showed higher positive factor 1 loadings, while C3 showed highly positive factor 2 loadings. The PCA analysis showed a combination contribution of microbial DOM signal and terrestrial DOM signal in the Yangtze estuary. Higher and more variable DOM abundance, aromaticity and molecular weight of surface sediment pore water DOM can be found in the southern nearshore than the other regions primarily due to the influence of frequent and intensive human activities and tributaries inflow in this area. The DOM abundance, aromaticity, molecular weight and fluorescence intensity in core of different depth were relative constant and increased gradually with depth. DOM in core was mainly composed of humic-like material, which was due to higher release of the sedimentary organic material into the porewater during early diagenesis.
基于 DOM 的丰度、紫外吸光度、分子量分布和荧光等多种参数，结合三维荧光激发发射矩阵光谱（F-EEMS）与平行因子和主成分分析（PARAFAC-PCA），研究了中国长江河口沉积物孔隙水中的溶解有机物质（DOM）。结果表明，长江河口孔隙水中的 DOM 变化很大，主要由低芳香度和低分子量物质组成。通过 PARAFAC 模型鉴定出三种腐殖质类物质（C1、C2、C4）和一种蛋白类物质（C3）。C1、C2 和 C4 表现出相同的趋势，非常相似。PCA 分析表明，样品在两个轴上的分离显示出 DOM 性质的差异。C1、C2 和 C4 同时表现出较高的因子 1 负荷，而 C3 则表现出高度的因子 2 负荷。PCA 分析表明，长江河口的 DOM 既有微生物 DOM 信号，也有陆地 DOM 信号的综合贡献。由于该地区频繁和强烈的人类活动以及支流的流入，近岸南部的表层沉积物孔隙水中 DOM 的丰度、芳香度和分子量更高，变化也更大。不同深度岩芯中 DOM 的丰度、芳香度、分子量和荧光强度相对恒定，且随深度逐渐增加。岩芯中的 DOM 主要由腐殖质类物质组成，这是由于在早期成岩作用期间，沉积物中的有机物质向孔隙水中释放更多。
