Chromophoric dissolved organic matter (CDOM) shows an approximate conservative behavior during estuary mixing, and can be used as the tracer of water mass movement. On the basis of the waters measured data in the Dayang Estuary on 6 May 2009, the optical properties and remote sensing retrieval model of CDOM were analyzed. The results show that CDOM mainly comes from terrigenous input in the study area, and its composition is relatively stable, so the study area belongs coastal Case II water region;a spectral slope Sg (275～295) and an absorption coefficient ag (400) all have indicative effect on the relative size of the CDOM molecular mass; CDOM exhibits a conservative mixing behavior, with the injection of freshwater in rivers, diffusion, water salinity increases, the high concentration CDOM from the river is diluted, so CDOM concentration decreases, meanwhile the high percentage of macromolecular humic acid contained the river water reduces, correspondingly, the high percentage of small molecular fulvic acid contained the ocean increases, so the Sg and M values increase; the performance of the model based on Rrs (531)/Rrs(551) sensitive band is the best, the coefficient of determination up to 0.84, so this model can be used as remote sensing retrieval model of CDOM in the Dayang Estuary.%有色溶解性有机物(CDOM)在河口混合过程中近似呈保守行为,可作为水团运动的示踪剂.基于2009年5月6日大洋河河口海域水体调查的实测数据,对该区域CDOM光学特性及遥感反演模型进行了研究,结果表明:研究区域CDOM主要来自河流输入,成分相对较稳定,属于典型的近岸二类水体区域;波长275～295 nm的光谱斜率和波长400 nm的吸收系数对CDOM分子量的相对大小均具有一定的指示作用;该区域的CDOM存在保守混合行为,随河流淡水的注入、扩散,水体盐度逐渐增大,河流淡水带入的高浓度CDOM被稀释,CDOM浓度逐渐减小,同时河流淡水中所含高比例的大分子腐殖酸降低,海水中所含高比例的小分子富里酸相应增加,使光谱斜率和波长250和365 mm处的吸收系数比值均增大;基于R<,rs>(531)/R<,rs>(551)敏感波段建立的模型表现最好,相关系数的二次方可达0.84,可作为大洋河河口海域CDOM遥感反演模型.
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