长江口有色溶解有机物光谱特性及其示踪溶解有机碳研究  

Optical Absorption Properties of Chromophoric Dissolved Organic Matter and the Tracing Implication of Dissolved Organic Carbon in the Yangtze River Estuary

作　　者：胡素征[1] 李桂菊[1] 李奕洁[1] 赵瑞华[1] 

机构地区：[1]天津科技大学海洋科学与工程学院,天津300457

出　　处：《天津科技大学学报》2015年第3期57-61,共5页Journal of Tianjin University of Science & Technology

基　　金：国家重点基础研究发展计划(973计划)资助项目(2013CB956600)

摘　　要：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0.45～3.10m^-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（R^2=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（R^2=0.852,5）,表明CDOM可以作为DOC的示踪物质.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 between a330 and DOC were discussed. a330 ranged from 0.45-3.10 m^-1 with the mean value of（1.34±0.90）m^-1 in the survey area. The significant negative linear correlations between CDOM/DOC and salinity（R^2=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 relationship between SUVA254 and salinity suggested the aromatic property of terrestrial CDOM was higher than that of marine CDOM. The relationship between SR and salinity followed the simple mixture model,which suggested that the physical mixing process should be the dominant factor controlling SR in the studied area. The relationship between CDOM and DOC（R^2=0.852,5）showed that CDOM was a promising tracer for terrestrial DOC.

关 键 词：长江口 有色溶解有机物 溶解有机碳 光谱特性 示踪物质 

分 类 号：TQ050.421[化学工程]