The optical absorption properties of chromophoric dissolved organic matter(CDOM)and the concentration of dissolved organic carbon(DOC)in surface water adjacent to the Yangtze River Estuary were studied from February to March 2014. The distribution of absorption coefficient(a330)of CDOM,spectral slope ratio(SR)and specific UV absorbance at 254,nm(SUVA254)were analyzed. The source of CDOM and the relationship betweena330 and DOC were discussed.a330 ranged from 0.45-3.10 m-1 with the mean value of(1.34±0.90)m-1in the survey area. The significant negative linear correla-tions between CDOM/DOC and salinity(R2=0.959,0,0.820,8)indicated CDOM and DOC in the Yangtze River Estuary were mainly terrestrial origin,and behaved conservatively during the mixing of fresh water with seawater. The negative rela-tionship between SUVA254and salinity suggested the aromatic property of terrestrial CDOM was higher than that of marine CDOM. The relationship betweenSR and salinity followed the simple mixture model,which suggested that the physical mix-ing process should be the dominant factor controllingSR in the studied area. The relationship between CDOM and DOC(R2=0.852,5)showed that CDOM was a promising tracer for terrestrial DOC.%通过测定2014年2、3月份长江口表层水中有色溶解有机物(CDOM)吸收光谱及溶解有机碳(DOC)质量浓度，分析了CDOM吸收系数a330的水平分布、光谱斜率比(SR)和比紫外吸光度(SUVA254)，探究了CDOM的来源及其与 DOC 的关系．研究表明：研究区域 a330范围为0.45～3.10,m-1，平均值为(1.34±0.90)m-1．CDOM 吸收光谱和 DOC质量浓度与盐度均呈负相关性(R2＝0.959,0，0.820,8)，表明二者的来源都是以陆源为主，且二者的河口混合行均表现为保守混合．由 SUVA254随盐度增大而减小得知，陆源 CDOM 相对于海源 CDOM 的芳香性较强．SR与盐度关系符合保守混合模型，说明研究区域的 SR 主要受物理作用影响．a330与 DOC 质量浓度呈正相关性(R2＝0.852,5)，表明CDOM可以作为DOC的示踪物质．
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