Characterization of CDOM of river waters in China using fluorescence excitation‐emission matrix and regional integration techniques
Characterization of CDOM of river waters in China using fluorescence excitation‐emission matrix and regional integration techniques
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DOI：
10.1002/2017jg003820
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发表时间：
2017-08
期刊：
影响因子：
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通讯作者：
Ying Zhao;K. Song;Y. Shang;Tiantian Shao;Z. Wen;Lili Lv
中科院分区：
文献类型：
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作者：
Ying Zhao;K. Song;Y. Shang;Tiantian Shao;Z. Wen;Lili Lv
利用2013年至2015年9月至11月的数据，首次采用激发发射矩阵光谱和荧光区域积分(FRI)方法研究了中国河水中荧光溶解有机物组分的空间特征。用FRI方法鉴定了1个酪氨酸(R1)、1个色氨酸(R2)、1个富里酸(R3)、1个微生物蛋白(R4)和1个腐殖酸(R5)组分。采用主成分分析方法分析了19 4个河水样品中5种有机氯农药组分(FRί(ί=1、2、3、4、5)和腐殖化指数的变化。中国流域七大流域(松花江、辽河、海河、黄淮、长江、珠江、入江)5种荧光成分的平均荧光强度和总荧光强度在空间上存在差异。当所有河水样品汇集在一起时，类富里酸的FR3和类腐殖质的FR5呈很强的正相关关系(R2=0.90，n=194)，表明两个异地FDOM组分R3和R5可能来自相似的来源。类色氨酸的FR2和类微生物蛋白的FR4之间存在中等强的正相关(R2=0.71，n=194)，这表明两个固有的FDOM组分R2和R4的部分可能来自一些共同的来源。而总异源物质FR(3+5)与总原生物质FR(1+2+4)呈弱相关(R2=0.40，n=194)。FR3(R2=0.69，n=194)、FR5(R2=0.79，n=194)与发色DOM(CDOM)的吸收系数a(254)呈显著的线性正相关，表明CDOM的吸收主要由异源FDOM组分R3和R5主导。
The spatial characteristics of fluorescent dissolved organic matter (FDOM) components in river waters in China were first examined by excitation‐emission matrix spectra and fluorescence regional integration (FRI) with the data collected during September to November between 2013 and 2015. One tyrosine‐like (R1), one tryptophan‐like (R2), one fulvic‐like (R3), one microbial protein‐like (R4), and one humic‐like (R5) components have been identified by FRI method. Principal component analysis (PCA) was conducted to assess variations in the five FDOM components (FRί (ί = 1, 2, 3, 4, and 5)) and the humification index for all 194 river water samples. The average fluorescence intensities of the five fluorescent components and the total fluorescence intensities FSUM differed under spatial variation among the seven major river basins (Songhua, Liao, Hai, Yellow and Huai, Yangtze, Pearl, and Inflow Rivers) in China. When all the river water samples were pooled together, the fulvic‐like FR3 and the humic‐like FR5 showed a strong positive linear relationship (R2 = 0.90, n = 194), indicating that the two allochthonous FDOM components R3 and R5 may originate from similar sources. There is a moderate strong positive correlation between the tryptophan‐like FR2 and the microbial protein‐like FR4 (R2 = 0.71, n = 194), suggesting that parts of two autochthonous FDOM components R2 and R4 are likely from some common sources. However, the total allochthonous substance FR(3+5) and the total autochthonous substances FR(1+2+4) exhibited a weak correlation (R2 = 0.40, n = 194). Significant positive linear relationships between FR3 (R2 = 0.69, n = 194), FR5 (R2 = 0.79, n = 194), and chromophoric DOM (CDOM) absorption coefficient a(254) were observed, which demonstrated that the CDOM absorption was dominated by the allochthonous FDOM components R3 and R5.