In order to strengthen the environmental management and improve the quality of water environment in the Chaohu Lake, the parallel factor analysis model and correlation analysis, three-dimensional fluorescence excitation-emission matrix (3 D-EEM) and ultraviolet-visible absorption spectrum (UV-Vis) were used to study the source and characteristics of DOM in water samples collected from the Pai River, one of the tributary rivers to the Chaohu Lake. The results showed that: (1) There are four kinds of fluorescent components in the DOM, of which the protein-like substances (including tryptophan and tyrosine) and fulvic acid-like substances (including ultraviolet fulvic acid-like and visible fulvic acid-like) accounted for 68. 1％ and 31. 9％ of the total fluorescence intensity components, respectively. (2) For the collected DOM, the fluorescence index (FI) was higher than 1. 9 and the biological index (BIX) was over 1. 0.The humification index (HIX) was less than 1. 5 in the upstream and varied from 1. 5 to 3 in the downstream. These indexes indicated that the DOM in the Pai River had obvious biological source characteristics, and the degree of water humification is relatively low. The zooplankton and biological bacteria in the overlying water body were uniform and their activities had obvious influence on the water environment. (3) UV-Vis could be used to identify the relative size of the DOM and UV-Vis analysis revealed that the DOM contained a lot of relatively stable organic matter. (4) The fluorescence intensity and ultraviolet-visible absorption coefficient[a (280) and a (355) ]of ultraviolet fulvic acid-like and tyrosine exhibited significant correlation, indicating that the sources and generation of component ultraviolet fulvic acid-like and tyrosine are consistent or concomitant. This study indicated that the spectral analysis can effectively track the land and biological source of DOM in Pai River.%派河是环巢湖流域重要入湖河流,为加强该流域环境综合治理,改善水环境质量,采集派河入河口水样,通过三维荧光光谱和紫外-可见吸收光谱,结合平行因子分析模型及相关性分析,进行DOM(dissolred organic matter,溶解性有机物)光谱学特性研究,分析派河水体DOM荧光组分来源及特征.结果表明:(1)水体中DOM含2类4种荧光组分,其中,类蛋白物质荧光组分(类色氨酸和类酪氨酸)占总组分荧光强度的68.1％,类富里酸物质(紫外类富里酸和可见类富里酸)占总组分荧光强度的31.9％;(2)采样点FI(荧光指数)大于1.9,BIX(生物源指数)大于1.0,派河上游HIX(腐殖化指数)小于1.5,下游HIX范围为1.5～3,表明派河DOM具有明显的生物源特征,水体腐殖化程度较低,上覆水体浮游动植物和生物细菌分布均匀且对水体环境有明显影响;(3)紫外-可见光吸收系数[a(280)和a(355)]可很好地表征派河水体中DOM相对含量,紫外-可见吸收光谱测定结果显示,水体中含大量性质相对稳定的有机物;(4)紫外类富里酸和类酪氨酸的荧光强度均与a(280)、a(355)呈显著正相关,表明水体DOM中紫外类富里酸和类酪氨酸组分的产生及来源具有一致性或相伴发生.研究显示,光谱分析法可有效表征派河水体中DOM兼具陆源和生物来源的双重特性.
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