高原湿地草海不同覆被土壤中溶解性有机质光谱特征  

Spectral Characteristics of Dissolved Organic Matter in Different Land Cover Soils in Caohai Plateau Wetland

作　　者：龙云川[1,2] 蒋娟 胡菁 万合锋 LONG Yunchuan;JIANG Juan;HU Jing;WAN Hefeng(Guizhou Institute of Biology,Guizhou Academy of Sciences,Guiyang 550009,China;Caohai Ecological Research Station,Guizhou Academy of Sciences,Bijie 553100,China;College of Resource and Environmental Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州科学院贵州省生物研究所,贵州贵阳550009 [2]贵州科学院草海生态站,贵州毕节553100 [3]贵州大学资源与环境工程学院,贵州贵阳550025

出　　处：《环境科学研究》2025年第4期896-906,共11页Research of Environmental Sciences

基　　金：贵州省科技计划项目(黔科合基础ZK[2023]一般233、黔科合支撑[2023]一般204);贵州省财政专项资金项目(梵净山、草海科研实验能力建设与工程维护)。

摘　　要：土地覆被类型差异会影响土壤有机质的生物地球化学循环,为探究高原湿地不同覆被类型土壤溶解性有机质(DOM)的分布特征及影响因素,以我国亚热带高原湿地生态系统的典型代表−贵州草海湿地为研究对象,基于紫外-可见吸收光谱(UV-Vis)、三维荧光光谱(3D-EEMs)及平行因子分析(PARAFAC)方法,解析草海湿地林地、耕地、草地、灌丛和滩涂等5种覆被土壤DOM的组成及特征。结果表明:①草海湿地土壤有机质平均含量为(51.11±10.58)g/kg,DOM含量为0.37~1.02 g/kg。DOM以植物源等陆源输入为主,呈弱腐殖化、较强自生源特征。土壤DOM共解析出3种组分,即类富里酸(C1)、陆源类腐殖质(C2)和类蛋白(C3)。②土地覆被类型影响土壤DOM特征,滩涂和灌丛土壤中C1组分占优势,林地和耕地土壤中C2组分相对占优,草地土壤中以C3组分为主。不同覆被土壤中DOM含量表现为滩涂>灌丛>耕地>草地>林地,林地土壤中DOM含量最低;耕地和草地土壤中DOM呈现较低的芳香化程度,滩涂和灌丛土壤中则有较高的芳香性,且DOM光谱参数呈表聚性。③共现网络分析和主成分分析(PCA)显示,C1组分与陆源输入密切相关,C2和C3组分与微生物活动联系紧密。冗余分析(RDA)和方差分解分析(VPA)表明,pH和总氮(TN)浓度是影响草海湿地土壤DOM光谱特征变化的关键因子。研究显示,高原湿地不同土地覆被通过植物资源输入、微生物转化及人类活动等多重因素对土壤DOM组成产生重要影响,其中pH和TN浓度是关键环境影响因子,研究结果可为高原湿地土壤碳循环提供基础数据。The variation in land cover significantly affects the biogeochemical processes of soil organic matter.This study takes Caohai Wetland in Guizhou,a typical representative of subtropical plateau wetland ecosystems in China,as the research object to explore the distribution characteristics and influencing factors of dissolved organic matter(DOM)in plateau wetland soils under different land covers.Ultraviolet-visible absorption spectroscopy(UV-Vis),three-dimensional fluorescence spectroscopy(3D-EEMs),and parallel factor analysis(PARAFAC)were applied to reveal the composition and source of DOM in soils from forestland,cultivated land,grassland,shrubland and mudflat in Caohai Wetland.The results indicated that the average content of soil organic matter in the Caohai Wetland was(51.11±10.58)g/kg,and the soil DOM concentration ranged from 0.37 g/kg to 1.02 g/kg.The DOM in soil predominantly originated from terrestrial sources,such as plant inputs,showing weak humification and relatively strong autochthonous characteristics.Three fluorescence components were identified in DOM by PARAFAC:fulvic-like component C1,terrestrial humic-like component C2,and protein-like component C3.Land cover types influenced the characteristics of soil DOM.Specifically,the C1 component was predominant in the mudflat and shrubland soils,the C2 component was dominant in the forestland and cultivated land soils,and the C3 component dominated in grassland soils.The DOM content in forestland was the lowest,with the order of DOM content from highest to lowest as:mudflat>shrubland>cultivated land>grassland>forestland.Cultivated land and grassland exhibited a low degree of aromatization,while mudflat and shrubland demonstrated relatively high aromaticity.The DOM spectral parameters displayed surface accumulation patterns.Cooccurrence network analysis and principal component analysis(PCA)revealed that the C1 component was closely related to terrestrial inputs,while the C2 and C3 components were closely related to microbial activities.Redundancy analys

关 键 词：溶解性有机质(DOM) 高原湿地 紫外-可见光谱 平行因子分析 共现网络 

分 类 号：X53[环境科学与工程—环境工程]