title: Identifying changes in dissolved organic matter content and characteristics by fluorescence spectroscopy coupled with self-organizing map and classification and regression tree analysis during wastewater treatment.
abstract: The stabilization of latent tracers of dissolved organic matter (DOM) of wastewater was analyzed by three-dimensional excitation-emission matrix (EEM) fluorescence spectroscopy coupled with self-organizing map and classification and regression tree analysis (CART) in wastewater treatment performance. DOM of water samples collected from primary sedimentation, anaerobic, anoxic, oxic and secondary sedimentation tanks in a large-scale wastewater treatment plant contained four fluorescence components: tryptophan-like (C1), tyrosine-like (C2), microbial humic-like (C3) and fulvic-like (C4) materials extracted by self-organizing map. These components showed good positive linear correlations with dissolved organic carbon of DOM. C1 and C2 were representative components in the wastewater, and they were removed to a higher extent than those of C3 and C4 in the treatment process. C2 was a latent parameter determined by CART to differentiate water samples of oxic and secondary sedimentation tanks from the successive treatment units, indirectly proving that most of tyrosine-like material was degraded by anaerobic microorganisms. C1 was an accurate parameter to comprehensively separate the samples of the five treatment units from each other, indirectly indicating that tryptophan-like material was decomposed by anaerobic and aerobic bacteria. EEM fluorescence spectroscopy in combination with self-organizing map and CART analysis can be a nondestructive effective method for characterizing structural component of DOM fractions and monitoring organic matter removal in wastewater treatment process.
authors: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Department of Urban Water Environmental Research, Chinese Research Academy of Environmental Science, Beijing 100012, China.
authors: Huibin
authors: H
authors: Yu
authors: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Department of Urban Water Environmental Research, Chinese Research Academy of Environmental Science, Beijing 100012, China. Electronic address: songyh@craes.org.cn.
authors: Yonghui
authors: Y
authors: Song
authors: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Department of Urban Water Environmental Research, Chinese Research Academy of Environmental Science, Beijing 100012, China.
authors: Ruixia
authors: R
authors: Liu
authors: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors: Hongwei
authors: H
authors: Pan
authors: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Department of Urban Water Environmental Research, Chinese Research Academy of Environmental Science, Beijing 100012, China.
authors: Liancheng
authors: L
authors: Xiang
authors: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Department of Urban Water Environmental Research, Chinese Research Academy of Environmental Science, Beijing 100012, China.
authors: Feng
authors: F
authors: Qian
mesh_terms: D006812:Humic Substances / Q000032:analysis*; D009930:Organic Chemicals / Q000032:analysis*; D012044:Regression Analysis; D013050:Spectrometry, Fluorescence / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000145:classification; D018508:Water Purification / Q000379:methods*
chemical_list: D006812:Humic Substances; D009930:Organic Chemicals; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Classification and regression tree analysis; Dissolved organic matter; Fluorescence spectroscopy; Self-organizing map; Wastewater