平原河网颗粒有机质光谱性质与流域土地利用变化的耦合关系分析  

Coupling analysis of particulate organic matter optical properties and land use in plains river networks

作　　者：陈永存 徐嘉骏 马增岭[2] 王婷 郭卫东 商栩[5] 瞿理印 CHEN Yongcun;XU Jiajun;MA Zengling;WANG Ting;GUO Weidong;SHANG Xu;QU Liyin(Zhejiang Reach Green Environmental Technology CO.,LTD,Wenzhou 325035;National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution,Wenzhou University,Wenzhou 325035;Institute of Eco-Environmental Sciences,Wenzhou Academy of Agricultural Sciences,Wenzhou 325006;State Key Laboratory of Marine Environmental Science,College of Ocean and Earth Sciences,Xiamen University,Xiamen 361012;Zhejiang Provincial Key Laboratory of Watershed Sciences and Health,Southern Zhejiang Water Research Institute(iWATER),Wenzhou Medical University,Wenzhou 325035)

机构地区：[1]浙江竟成环保科技有限公司,温州325035 [2]温州大学城镇水污染生态治理技术国家地方联合工程研究中心,温州325035 [3]温州市农业科学研究院生态环境研究所,温州325006 [4]厦门大学近海海洋环境科学国家重点实验室,厦门361012 [5]温州医科大学浙南水科学研究院,浙江省流域水环境与健康风险研究重点实验室,温州325035

出　　处：《环境科学学报》2024年第11期396-403,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金项目(No.42276041);浙江省教育厅项目(No.Y202352541,Y202352708)。

摘　　要：流域土地利用变化是影响河流颗粒有机质(POM)循环的重要因素.此过程在水动力条件较弱的平原河网系统可能更为强烈,但目前相关研究较少.因此,本研究以温瑞塘河河网作为典型研究区域,将POM碱提方法(BEPOM)与紫外-可见光光谱及三维荧光光谱技术相结合探讨土地利用变化对河流POM含量及光学性质的影响.结果显示,温瑞塘河颗粒有机碳(POC)浓度为0.2~8.95 mg·L^(-1),BEPOM丰度与POC浓度呈显著正相关,二者均呈现城市支流区>城市干流区>城市-农田混合区>山区的空间分布模式.基于土地利用与POM数据的冗余分析结果显示城市河段POM受人为输入和内源自生影响,相对分子质量较小,类蛋白质组分丰度高.在水动力条件较弱的城市支流河段,POM的生源信号更加强烈.混合区类腐殖质组分的相对丰度最高,农田河畔土壤输入使混合区POM较城市区和山区表现出更强的陆源特性.山区POM总荧光组分强度最低,但混合组分的相对丰度最高,主要来源于植物凋落物的微生物不完全降解产物.本研究为评估土地利用对河流POM的影响提供了理论依据.Land-use change is a significant factor influencing riverine particulate organic matter(POM)dynamics.This disturbance appears more pronounced in plain river networks with weak hydraulic conditions;however,the studies to assess this impact are scarce.This study utilized the Wenruitang River(Wenzhou,Zhejiang Province)as a representative plain river system to explore the impact of land-use change on POM concentration and optical properties.We used the base-extraction method for POM(BEPOM)combined with UV-visible spectroscopy and three-dimensional fluorescence spectroscopy techniques to assess POM characteristics.Particulate organic carbon(POC)concentrations in the Wenruitang River ranged from 0.2 to 8.95 mg·L^(-1).The abundance of BEPOM was positively correlated with POC(r=0.75,p<0.05)and exhibited a similar land-use spatial distribution pattern:urban tributary zone>urban mainstream zone>urban-agricultural mixed zone>mountain zone.Redundancy analysis based on land use and POM data indicated that POM in urban rivers was influenced by both anthropogenic inputs and in situ production,characterized by lowmolecular-weight and high protein-like components.In urban tributaries with weaker hydraulic exchange,the autochthonous POM signal was more pronounced.The relative abundance of humic-like components was highest in the mixed zone,wherein inputs from riparian soils in cropland areas resulted in stronger terrestrial signals compared to the urban and mountain zones.Although the total fluorescence intensity of BEPOM in the mountain zone was the lowest,the relative abundance of mixed components was the highest,suggesting a contribution from incompletely degraded plant litter.This study provides a reference data for assessing the influence of land use on riverine POM cycling in plain river networks.

关 键 词：颗粒有机质 平原河网 土地利用 三维荧光 平行因子分析 

分 类 号：X522[环境科学与工程—环境工程]