长三角典型城郊流域生物可降解性有机质的分布及影响因素  

Distribution of Biodegradable Dissolved Organic Matter and Its Affecting Factors in a Typical Peri-urban Watershed in Yangtze River Delta

作　　者：吴文雨 马菁晟 杨磊[4] 李敏[4] 唐剑锋 WU Wen-yu;MA Jing-sheng;YANG Lei;LI Min;TANG Jian-feng(Key Laboratory of Urban Environment and Health,Institute of Urban Environment,Chinese Academy of Sciences,Xiamen 361021,China;School of Ecological Engineering,Shanghai Institute of Technology,Shanghai 201418,China;Jurong Group of Jiangsu Science and Technology Mayor Group,Jurong 212400,China;State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China)

机构地区：[1]中国科学院城市环境研究所城市环境与健康重点实验室,厦门361021 [2]上海应用技术大学生态技术与工程学院,上海201418 [3]江苏省科技镇长团句容团,句容212400 [4]中国科学院生态环境研究中心城市与区域生态国家重点实验室,北京100085

出　　处：《环境科学》2023年第1期210-218,共9页Environmental Science

基　　金：国家自然科学基金项目(31971489)。

摘　　要：快速城镇化改变了流域水体中碳的生物地球化学循环过程,生物可利用性的溶解性有机质组分是其中最为关键的一环,辨识生物可降解性有机质(BDOM)的时空分布特征及其影响因素对流域水质管控具有重要意义和应用价值.以长三角地区典型城郊流域樟溪为研究对象,根据流域地形特征、土地利用及人类活动强度布设监测点位,于2019年分别在雨季和旱季采样,利用三维荧光平行因子(EEM-PARAFAC)方法结合源汇景观模型研究流域水体BDOM的时空分布特征.结果表明,流域中生物可降解性有机碳浓度范围在0.57~6.80 mg·L^(-1),且具有较高的时空异质性,人类活动强度较高的区域水体中BDOM的浓度也相对较高,且雨季显著高于旱季.EEM-PARAFAC分析结果表明,流域BDOM主要包括陆源腐殖质(C1)和类蛋白质类(C2)这2种荧光组分.流域BDOM及其陆源腐殖质荧光组分主要受土地利用和人类活动的影响,其浓度与农业及城镇用地比例和源汇景观负荷比(LWLI)关系密切,表明城镇化过程中人类活动是影响BDOM分布的重要因素.Dissolved organic matter(DOM)plays key roles in the carbon biogeochemical cycle,and biodegradable dissolved organic matter(BDOM)is one of the key fractions of DOM.Rapid urbanization and intensive human activities substantially influence the distribution of DOM at the watershed scale.Identifying the spatial and temporal variability in BDOM has become an important and urgent issue of water quality control in rapid urbanization areas.However,limited studies have been conducted to explore the role of human activities on the occurrence and distribution of BDOM in peri-urban watersheds.In this study,the spatial and temporal distribution of BDOM and related affecting factors were investigated in a typical peri-urban watershed(Zhangxi watershed)located at Ningbo City in Yangtze River Delta.Water samples were collected in wet and dry seasons in 2019 based on topographic features,land use,and intensity of human activities.The BDOM were characterized by fluorescence excitation-emission matrix and parallel factor analysis(EEM-PARAFAC),and land use patterns were analyzed using the Source-Sink Landscape Model.The results of this study showed that the BDOM concentrations ranged from 0.57 to 6.80 mg·L^(-1).Obvious spatial and temporal heterogeneities of BDOM were found at the watershed scale,and significantly higher concentrations of BDOM were observed in the wet season than those in the dry season.Furthermore,relatively high concentrations of BDOM were found in areas with relatively higher intensive human activities.Two fluorescent components(a terrestrial humic-like substance and protein-like substance)were observed using the PARAFAC model.The results of spatial analysis showed that terrestrial humic-like fluorescent components were closely positively correlated with anthropogenic parameters(percentages of agricultural and urban land and ratio of source and sink landscapes).The results showed that the occurrence and distribution of BDOM were strongly influenced by human activities,which could provide scientific guidance for w

关 键 词：城郊流域 溶解性有机质(DOM) 生物可降解性有机质(BDOM) 土地利用格局 平行因子分析 

分 类 号：X52[环境科学与工程—环境工程]