厦门湾陆源入海排污口有色溶解有机物(CDOM)光吸收特性及荧光光谱研究

Light absorption and fluorescence properties of chromophoric dissolved organic matter(CDOM) of land- based outfalls in Xiamen Bay

本研究在厦门地区选择4个陆源入海排污口DL（埭辽），XL（杏林），TA（同安），XA（翔安）及其相应邻近海域，在2009年8月、2010年5月及2010年8月，共组织3个航次，对排污口及相应邻近海域水体的有色溶解有机物（CDOM）开展调查。排污口站位水体CDOM的吸收系数ag（355）介于2．84—15．91m^-1，平均值为7．85m^-1；排污口邻近海域水体CDOM的吸收系数ag（355）介于0．51～2．33m^-1，平均值为1．54m^-1。CDOM吸收系数ag（355）与COD浓度的线性函数相关性（R^2=0．745），优于CDOM吸收系数ag（355）与BOD5的相关性（R^2=0．629）。同时，通过PARAFAC方法对CDOM的三维荧光光谱（EEMs）的研究中，识别出的W2组分在天然水体中鲜有检出，它与“X”组分相似，可能作为排污152及邻近海域水体中的一个特征荧光吸收纽分。

Study on chromophoric dissolved organic matter （CDOM） of four land - based outfalls, named Dailiao （DL）, Xinglin （XL）, Tong＇an （TA） and Xiang＇an （XA） in Xiamen Bay, was carried out in August 2009, May 2010 and August 2010. The CDOM absorption coefficient at 355 nm, as （355）, ranged from 2. 84 · 15.91 m^-1 and the average was 7.85 m^-1 at the outfalls. The ag （355） of sea water adjacent to outfalls varied from 0. 51 -2.33 m^- 1 and the average was 1.54 m^-1. Positive linear correlation was found between ag （355） and COD, BOD5 concentration and the correlation of COD （ R2 = 0. 745） was better than BOD5 （ R2 = 0. 629）. We also applied the PARAFAC method to the study of three - dimensional fluorescence excitation - emission matrix spectroscopy. Three components were distinguished and W2 component was rarely detected in natural water body and was similar to X component, moreover, it could be considered as a characteristic fluorescence component of outfalls and adjacent sea water.