店埠河农业小流域水体溶解性有机质光谱时空分布特征  

Spatiotemporal Distribution Characteristics of Dissolved Organic Matter Spectrum in the Agricultural Watershed of Dianbu River

作　　者：杨欣 夏敏 叶寅[1,2] 王静 YANG Xin;XIA Min;YE Yin;WANG Jing(Institute of Soil and Fertilizer,Anhui Academy of Agricultural Sciences,Hefei 230031,China;Key Laboratory of Nutrient Cycling and Resources Environment of Anhui Province,Hefei 230031,China)

机构地区：[1]安徽省农业科学院土壤肥料研究所,安徽合肥230031 [2]养分循环与资源环境安徽省重点实验室,安徽合肥230031

出　　处：《光谱学与光谱分析》2023年第9期2983-2988,共6页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(31901154),安徽省农业科学院院立科研团队(2022YL022)资助。

摘　　要：店埠河农业小流域是南淝河最大的支流,探究该流域水体溶解性有机质(DOM)的时空演变机制对于了解其水生生态系统至关重要。该研究结合水体的三维荧光光谱和紫外-可见光谱,采用平行因子分析(PARAFAC)方法对测定的三维荧光光谱矩阵进行组分提取,分析该流域特定时段的水体DOM荧光组分及比例,结合荧光参数(荧光指数FI、自生源指标BIX以及腐殖化指标HIX)和紫外-可见光谱吸收特征参数(α_(254)、E_(2)/E_(3))分析店埠河农业小流域水体DOM时空特征。实验结果显示:店埠河农业小流域在该特定时段(2020年9月-2021年4月)水体DOM包含2个有效的荧光组分,分别为1种类腐殖质物质(类富里酸组分)和1种类蛋白质物质(低激发类色氨酸组分),两个组分各占比例分别为53.9%和46.1%;水体三个荧光参数(FI、BIX、HIX)在不同季节(9月秋季、1月冬季和4月春季)之间的荧光参数呈现显著的季节变化差异,指明DOM总体上受陆源和内源物质的综合影响,具有强腐殖化、弱自生源特征;紫外-可见光谱吸收特征参数(α_(254)、E_(2)/E_(3))表明1月冬季水体的DOM相对浓度和分子量大小均低于其他两个季节(9月秋季和4月春季),而各采样点DOM分子量大小和相对浓度从河流上游到下游均未呈现明显的区域变化趋势。该研究综合流域水体三维荧光光谱特征和紫外-可见光谱吸收特征,示踪了店埠河农业小流域水体特定时段DOM的组分来源,分析了其时空分布特征,从而为该流域的生态环境综合治理提供可靠的理论依据。The agricultural watershed of Dianbu River is the largest tributary of Nanfeihe River,so it is important to explore the temporal and spatial evolution mechanism of dissolved organic matter(DOM)in this watershed to understand its aquatic ecosystem.In this study,we comprehensively utilized the 3-D fluorescence spectrum and UV-visible spectrum of water bodies to track the DOM characteristics of this watershed.PARAFAC method was adopted to extract DOM components from the measured 3-D fluorescence spectral matrix.Moreover,we analyzed the DOM fluorescence components and the proportion of water bodies in a specific period.DOM's temporal and spatial characteristics in Dianbu River agricultural watershed were analyzed by combining the fluorescence parameters(FI,autobiogenic index BIX and humification index HIX)and UV-visible absorption characteristic parameters(α_(254),E_(2)/E_(3)).The results show that the watershed water DOM in the specific period(September 2020-April 2021)contains two effective components of fluorescence,one kind of humus(fulcrum acid-like component)and one kind of protein(Low excitation tryptophan-like component),the proportion of two components were 53.9%and 46.1%respectively;The fluorescence parameters of the three water bodies(FI,BIX and HIX)showed significant seasonal variations in different seasons(autumn in September,winter in January and spring in April),indicating that DOM was generally influenced by terrigenous and endogenous substances,but had strong humification and weak authigenic characteristics.The characteristic absorption parameters of the UV-visible spectrum(α_(254),E_(2)/E_(3))indicated that the relative concentration and molecular weight of DOM in winter water in January were lower than those in the other two seasons(autumn in September and spring in April),while the molecular weight and relative concentration of DOM at each sampling point showed no obvious regional variation trend from upstream to downstream in the watershed.In this study,the three-dimensional fluorescence spectr

关 键 词：店埠河流域 溶解性有机质(DOM) 三维荧光光谱(EEMs) 紫外-可见吸收光谱(UV-Vis) 

分 类 号：X522[环境科学与工程—环境工程]