Characterization and spacial distribution variability of chromophoric dissolved organic matter (CDOM) in the Yangtze Estuary.
Characterization and spacial distribution variability of chromophoric dissolved organic matter (CDOM) in the Yangtze Estuary.
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DOI：
10.1016/j.chemosphere.2013.09.044
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发表时间：
2014
期刊：
影响因子：
8.8
通讯作者：
Ying Wang;Di Zhang;Zhenyao Shen;J. Chen;C. Feng
中科院分区：
文献类型：
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作者：
Ying Wang;Di Zhang;Zhenyao Shen;J. Chen;C. Feng
采用三维荧光激发发射矩阵光谱（F-EEMs）结合并行因子主成分分析（PARAFAC-PCA），从丰度、腐殖化程度和来源等方面研究了长江口有色溶解有机物（CDOM）的空间分布特征及其数量和质量。结果表明，从河口上游到下游，CDOM的丰度逐渐降低，芳香度逐渐增加。孔隙水中CDOM的丰度和腐殖化程度均高于表层和底层沃茨。两个腐殖类组分（C1和C3）和一个类胡萝卜素组分（C2）被确定使用PARAFAC模型。通过PCA对样本的分离突出了DOM属性的差异。组分C1和C3同时显示正因子1负荷和几乎为零的因子2负荷，而C2显示高度正的因子2负荷。C1和C3非常相似，与A355和DOC有直接关系。孔隙水中CDOM含量沿着江向沿岸增加，主要受C1和C3的影响，主要来源于长江入流泥沙的矿化和沉积。表层和底层沃茨中CDOM以C2为主，尤其是在受人为活动影响较大的多支流入流中。微生物降解的外源性废物从支流输入和岸边排放的CDOM在表层和底层沃茨的主要来源。
The spatial characteristics and the quantity and quality of the chromophoric dissolved organic matter (CDOM) in the Yangtze Estuary, based on the abundance, degree of humification and sources, were studied using 3D fluorescence excitation emission matrix spectra (F-EEMs) with parallel factor and principal component analysis (PARAFAC–PCA). The results indicated that the CDOM abundance decreased and the aromaticity increased from the upstream to the downstream areas of the estuary. Higher CDOM abundance and degrees of humification were observed in the pore water than that in the surface and bottom waters. Two humic-like components (C1 and C3) and one tryptophan-like component (C2) were identified using the PARAFAC model. The separation of the samples by PCA highlighted the differences in the DOM properties. Components C1 and C3 concurrently displayed positive factor 1 loadings with nearly zero factor 2 loadings, while C2 showed highly positive factor 2 loadings. The C1 and C3 were very similar and exhibited a direct relationship with A355 and DOC. The CDOM in the pore water increased along the river to the coastal area, which was mainly influenced by C1 and C3 and was significantly derived from sediment remineralization and deposition from the inflow of the Yangtze River. The CDOM in the surface and bottom waters was dominated by C2, especially in the inflows of multiple tributaries that were affected by intensive anthropogenic activities. The microbial degradation of exogenous wastes from the tributary inputs and shoreside discharges were dominant sources of the CDOM in the surface and bottom waters.