Ultraviolet humic-like component contributes to riverine dissolved organic matter biodegradation

作     者：Maofei Ni Siyue Li Maofei Ni;Siyue Li

作者机构：College of Eco-Environmental EngineeringGuizhou Minzu UniversityGuiyang 550025China Research Center for Environmental Ecology and EngineeringSchool of Environmental Ecology and Biological EngineeringWuhan Institute of TechnologyWuhan 430205China The karst environmental geological hazard prevention laboratory of Guizhou Minzu UniversityGuiyang 550025China Key Laboratory of Reservoir Aquatic EnvironmentResearch Center for EcohydrologyChongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2023年第124卷第2期

页      面：165-175页

核心收录：

学科分类：08[工学] 0815[工学-水利工程] 

基　　金：financially supported by the National Natural Science Foundation of China (Nos. 31670473 and 42107091) 

主　　题：Dissolved organic matter(DOM) Sequential biodegradation Recalcitrant compounds Component and fate Fluorescence analysis 

摘      要：Biological degradation of dissolved organic matter(DOM)regulates its structure and fate in river *** views suggested that labile components were dominantly consumed by microbial *** we provide new observations that a part of recalcitrant compounds largely contribute to riverine DOM *** excitationemission matrix fluorescent spectroscopy combined with peak picking and parallel factor analysis are used to explore component variability during DOM ***-like and tryptophan-like DOM are the primary components of riverine DOM,with proportion contributions of 39%–82% and 16%–61% for % of the maximumfluorescence intensity,*** 56 days of aerobic incubation in the dark,large amounts of tyrosine-like DOM generation are *** temperature enhances the decomposition of ultraviolet humiclike substance and further stimulates labile DOM bio-mineralization into carbon ***,averaged proportions of amino acid compositions(peak B and T)markedly increase(p0.05)as the humic-like compositions(peak A,M and C)decrease after DOM incubation,suggesting incomplete degradation of refractory DOM from high-molecular to low-molecular weight *** findings support the new notion of the continuous DOM biodegradation in a mode as“steps by steps,contributing to a new understanding of carbon cycling for the UN Sustainable Development Goal.