Simulated photo-degradation of dissolved organic matter in lakes revealed by three-dimensional excitation-emission matrix with regional integration and parallel factor analysis  

作　　者：Jin Zhang Fanhao Song Tingting Li Kefu Xie Huiying Yao Baoshan Xing Zhongyu Li Yingchen Bai 

机构地区：[1]School of Environmental and Safety Engineering,Changzhou University,Jiangsu 213164,China [2]State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China [3]College of Water Sciences,Beijing Normal University,Beijing 100875,China [4]Department of Chemistry,Beijing Normal University,Beijing 100875,China [5]Stockbridge School of Agriculture,University of Massachusetts,Amherst,MA01003,USA

出　　处：《Journal of Environmental Sciences》2020年第4期310-320,共11页环境科学学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.41573130);BNU Interdisciplinary Research Foundation for First-Year Doctoral Candidates(No.BNUXKJC1802)

摘　　要：Simulated photo-degradation of fluorescent dissolved organic matter(FDOM) in Lake Baihua(BH) and Lake Hongfeng(HF) was investigated with three-dimensional excitationemission matrix(3 DEEM) fluorescence combined with the fluorescence regional integration(FRI),parallel factor(PARAFAC) analysis,and multi-order kinetic models.In the FRI analysis,fulvic-like and humic-like materials were the main constituents for both BH-FDOM and HF-FDOM.Four individual components were identified by use of PARAFAC analysis as humic-like components(C1),fulvic-like components(C2),protein-like components(C3) and unidentified components(C4).The maximum 3 DEEM fluorescence intensity of PARAFAC components C1-C3 decreased by about 60%,70% and 90%,respectively after photo-degradation.The multi-order kinetic model was acceptable to represent the photo-degradation of FDOM with correlation coefficient(Radj2)(0.963-0.998).The photo-degradation rate constants(kn) showed differences of three orders of magnitude,from 1.09 × 10-6 to 4.02 × 10-4 min-1,and half-life of multi-order model(T1/2n)ranged from 5.26 to 64.01 min.The decreased values of fluorescence index(FI) and biogenic index(BI),the fact that of percent fluorescence response parameter of Region I(PⅠ,n) showed the greatest change ratio,followed by percent fluorescence response parameter of Region II(PⅡ,n,while the largest decrease ratio was found for C3 components,and the lowest T1/2n was observed for C3,indicated preferential degradation of protein-like materials/components derived from biological sources during photodegradation.This research on the degradation of FDOM by 3 DEEM/FRI-PARAFAC would be beneficial to understanding the photo-degradation of FD OM in natural environments and accurately predicting the environmental behaviors of contaminants in the presence of FDOM.

关 键 词：Fluorescent dissolved organic matter PHOTO-DEGRADATION Fluorescence regional integration Parallel factor analysis Three-dimensional excitationemission matrix Multi-order kinetic models 

分 类 号：X50[环境科学与工程—环境工程]