三维荧光组合PARAFAC分析评估城市水体DOM特征分布与来源

摘要

Excitation-emission matrix (EEMs ) spectrum combined with Parallel factor analysis (PARAFAC)was used to investigate the fluorescent characteristic distribution and source of dissolved organic matter (DOM)in urban water bodies.Cluster analysis was also applied to discuss their differ-ences.Five effective PARAFAC fluorescent components were extracted,including 2 humic-like and 3 protein-like substances.Protein-like substances are the main components of DOM.Fluorescence index (FI),recent autochthonous contribution (BIX),and humification index (HIX)indicates DOM are mainly derived from bacteria and microbes.Water bodies further are divided into three groups,inclu-ding clean-water bodies,slight-pollution water bodies,and heavy-pollution water bodies.Results shows that,EEMs spectrum of urban water bodies has the feature of protein-like substances caused by human activities.%基于三维荧光光谱组合平行因子(PARAFAC)分析,考察了太湖流域某城市环境水体溶解性有机物(DOM)的荧光分布特征和来源,结合聚类分析评估环境水体特征差异.从环境水体DOM荧光光谱中解析出5个有效PARAFAC荧光组分,包括2种腐殖酸类物质和3种蛋白质类物质,蛋白质类组分是水中DOM的主要组成部分.荧光指数FI、腐殖化指数HIX和生物源指数BIX均显示,城市环境水体DOM主要来源于细菌、微生物等生物来源.聚类分析进一步将环境水体分为洁净水体、轻污染水体、较重污染水体等3类.研究结果表明,城市河道水体荧光光谱带有明显的人类活动影响的类蛋白有机物特征.