基于光谱特征的太湖表层水体有色可溶性有机物的光化学降解  

Photochemical Degradation of Chromophoric Dissolved Organic Matter in Surface Water of Taihu Lake:Based on Spectral Features

作　　者：张楠楠 胡斌[2] Zhang Nan-nan;Hu Bin(Jiangsu Academy of Environmental Industry and Technology Corp.,Nanjing 210019,China;Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education,Hohai University,Nanjing,210024,China)

机构地区：[1]江苏环保产业技术研究院股份公司,南京210019 [2]河海大学浅水湖泊综合治理与资源开发教育部重点实验室,南京210024

出　　处：《污染防治技术》2024年第1期61-65,共5页Pollution Control Technology

摘　　要：本文利用紫外可见光吸收光谱、三维荧光光谱及同步荧光光谱开展了太湖表层水体有色可溶性有机物(CDOM)的光化学降解研究。结果表明,11天自然光照期间,太湖不同湖区CDOM的溶解态有机碳含量没有明显变化,吸收系数A_(254)和特定吸光度SUVA呈显著地下降趋势,而吸收光谱斜率S_(R)则呈现上升趋势。三维荧光光谱结果表明,类腐殖质荧光组分的荧光强度随光照时间的增加呈现明显的下降趋势,而类蛋白质组分则呈现波动的变化趋势。这一系列结果表明,光照能够促使大分子的类腐殖质转化为小分子的有机质。同步荧光光谱结合二维相关光谱分析进一步表明太湖表层水体CDOM中不同组分的光降解顺序大致为类腐殖质类→类蛋白质酪氨酸→类蛋白质色氨酸。This study investigated the photochemical degradation of chromophoric dissolved organic matter in the surface water of Taihu Lake using ultraviolet-visible absorption spectroscopy,three-dimensional fluorescence spectroscopy,and synchronous fluorescence spectroscopy.The results showed that during an 11 day natural irradiation exposure period,the dissolved organic carbon content of CDOM in different areas of Taihu Lake did not change significantly.However,the absorption coefficient A_(254) and specific ultraviolet absorbance SUVA exhibited a significant decrease trend,while the spectral slope S_(R) showed an increasing trend.The results of three-dimensional fluorescence spectroscopy indicated that the fluorescence intensity of humic-like fluorescent components decreased significantly with increasing irradiation exposure time,while the protein-like components exhibited a fluctuating trend.These results suggest that irradiation exposure can promote the transformation of high molecular weight humic-like substance into small molecular weight organic matter.Further analysis using synchronous fluorescence spectroscopy combined with two-dimensional correlation spectroscopy revealed that the photodegradation sequence of different components in CDOM in the surface water of Taihu Lake was roughly humic-like substances→protein-like tryptophan→protein-like tyrosine.

关 键 词：有色可溶性有机物 光降解 荧光光谱 紫外可见光吸收光谱 太湖 

分 类 号：X142[环境科学与工程—环境科学]