阳澄湖原水中溶解性有机物变化特征及来源分析

Variation Characteristics and Source Analysis of Dissolved Organic Matter in Yangcheng Lake Raw Water

为保护饮用水厂的安全运行,也为阳澄湖水质管理提供科学依据,文中以阳澄湖原水为分析对象,分析其溶解性有机物的变化特征及来源。研究结果表明,阳澄湖原水溶解性有机碳的质量浓度在2.14~4.94 mg/L,总体呈现夏季高、冬季低的特征。原水中溶解性有机物主要是由相对分子质量小于3 kDa的小分子组成,占比约80%,6月—次年1月相对分子质量分布无显著差异。三维荧光光谱显示,阳澄湖原水自生源特征明显,溶解性有机物主要来源于微生物对有机物的分解,腐殖化程度较低。阳澄湖原水中溶解性有机物荧光物质主要有两类,其中,类蛋白荧光物质类酪氨酸、类色氨酸和小分子类酪氨酸来源之间存在较强关联性,类腐殖质荧光物质为紫外区类富里酸,荧光强度主要由类蛋白荧光贡献。

In order to protect the safe operation of drinking water treatment plant and provide scientific basis for water quality management of Yangcheng Lake,the raw water of Yangcheng Lake was taken as the analysis object in this paper to analyze variation characteristics and sources of dissolved organic matter.The results showed that dissolved organic carbon of Yangcheng Lake raw water was 2.14~4.94 mg/L,which was generally characterized high in summer and low in winter.Dissolved organic matter in raw water was mainly composed of small molecules with relative molecular weight less than 3 kDa,accounted for about 80%.Moreover,there was no significant difference in the relative molecular weight distribution of dissolved organic matter from June to January.The threedimensional fluorescence spectrum showed that Yangcheng Lake raw water had strong self-generated characteristics,and the dissolved organic matter mainly came from the decomposition of organic matter by microorganisms,with weak humification characteristics.Fluorescent substances of dissolved organic matter in Yangcheng Lake raw water were mainly classified into two categories,among which,the sources of protein-like fluorescent substances such as tyrosine,tryptophan and small molecule tyrosine were strongly correlated.The humic-like fluorescent substances were ultraviolet fulvic acid.The fluorescence intensity was mainly contributed by protein-like fluorescence.