长江(万州段)水体溶解性有机物的荧光光谱分析

FLUORESCENCE SPECTRAL CHARACTERISTICS OF DISSOLVED ORGANIC MATTER IN WATER OF THE YANGTZE RIVER

按照河床形态、水文条件、排污口分布、支流状况等特点从长江万州段及长江支流苎溪河选取8个断面进行采样,对水样中溶解性有机物(DOM)的荧光光谱特征进行了分析和研究。利用日立F-4500荧光分光光度计对长江水、普通自来水和纯水在紫外光激励下产生的荧光光谱及其特性进行了比较研究。同时,研究了不同水样、不同取样点的水体DOM的荧光特性和三维荧光光谱图。结果表明:长江水在波长290 nm左右的紫外光激励下能产生较强的荧光。荧光峰是350~550 nm范围的宽谱峰,荧光峰值波长在450 nm左右。但是不同取样点水样的荧光峰强度明显有差异,在4号、5号、2号取样点的水样荧光强度明显高于其他取样点,这与采样点附近污染源排放有明显的关系。该研究方法可作为鉴别水质污染的一种有效的手段。

The concent ration of dissolved organic matter （DOM） is an important index to assess natural water quality. Fluorescence fingerprint technique was widely used to characterize dissolved organic matter （DOM） in river from different sources. In this paper,the authors analysised the fluorescence spectral characteristics of different series water by fluorescence method. According to the channel transverse, hydrological condition, sewage outfall distribution, and branch status, experimental samples were collected from eight cross-sections in the Wanzhou section of the Yangtze River and Zhuxi River. The result showed that an expanse fluorescence can be generated from emission wavelengths 350 nm to 550 nm when the ultraviolet excitation wavelengths are 290 nm. The authors also studied the 3-dimension fluorescence spectral characteristics of different sample of water,different sites. Higher peak values were found in 4 # , 5 # and 2 # water sample. In 4 # and 5 # water samples Dora content is higher due to the pollution of Zhuxi river. But in 2 sample due to upstream chemical factorys. The peak values are generally related with the point pollution of these regions. Characters of this method are sensitive, simple and fast. It can be an effective measure method of water quality.