摘要
溶解性有机质(DOM)是土壤有机质中最活跃的成分,影响重金属迁移、转化过程,研究两者间相关性对环境监测和污染评价具有重要价值。采集位于小兴安岭的黑龙江省茅兰沟国家级自然保护区内典型针阔叶混交林表层(0~30 cm)土壤,采用三维荧光光谱-平行因子分析法,揭示林地土壤DOM荧光光谱特征,并进一步分析DOM荧光组分与重金属含量间相关性。结果表明:林地土壤DOM荧光指数在1.468~1.635之间,平均值为1.531,其来源兼具自生源和外生源特征;生物指数在0.563~0.646之间,平均值为0.603,新近自生源贡献率低;腐殖化指数在4.607~8.993之间,平均值为6.491,腐殖化程度不高。林地土壤DOM荧光光谱中共识别出3类5种荧光组分,包括类腐殖质(紫外类富里酸C1和可见类富里酸C2)、类腐殖酸(胡敏酸C3)和类蛋白质(类酪氨酸C4和类色氨酸C5)。类腐殖质占总组分和比例(60.12%)最大,显著高于类腐殖酸和类蛋白质,类腐殖酸占总组分和比例(11.25%)最小。C1、 C2和C3间均具有明显正相关性,C5与其余4种荧光组分均成显著负相关。5种荧光组分与荧光指数间均具有显著的相关性,仅C5与荧光指数成正相关。林地土壤重金属含量空间分布具有较大差异,As与Cr, Cu、 Ni与Zn, Hg与Pb均具有显著正相关性,Hg与Cu、 Ni及Zn, Cr与Pb均具有显著负相关性。3类荧光组分与As、 Cr和Pb的相关性均不显著,而均与Zn具有显著的相关性。同时,类腐殖质与Cu和Hg成显著相关,类腐殖酸与Cu、 Hg和Ni显著相关,而类蛋白质与Ni显著相关。研究结果可为茅兰沟国家级自然保护区林地土壤环境监测提供基础数据,为小兴安岭典型针阔叶混交林土壤重金属污染评价提供参考依据。
Dissolved organic matter(DOM)is the most active component in soil organic matter,affecting heavy metal's migration and transformation.Studying their correlation is of great value for environmental monitoring and pollution assessment.In this study,the topsoil(0~30 cm)was collected from the typical coniferous and broad-leaved mixed forest in Heilongjiang Province Maolan'gou National Nature Reserve,located in Xiaoxing'anling,China,and three-dimensional fluorescence spectroscopy-parallel factor analysis method was used to reveal the characteristics of forest soil DOM fluorescence spectra,and further to analyze the correlation between DOM fluorescence component and heavy metal content.The results showed that the forest soil DOM fluorescence index ranged from 1.468 to 1.635,with an average value of 1.531,indicating the DOM source had both autogenic and exogenous characteristics.The biological index ranged from 0.563 to 0.646,with an average value of 0.603,indicating a low contribution rate of recent autogenic source;The humification index ranged from 4.607 to 8.993,with an average value of 6.491,indicating a low degree of humification.Threetypes of fivekinds of fluorescent components were identified from the forest soil DOM fluorescence spectrum,including humus-likesubstances[ultraviolet fulvic acid-like component(C1)and visible fulvic acid-like component(C2)],humic acid-like substance(humic acid component,C3),and proteinlike substance[tryptophanlike component(C4)and tyrosinelike component(C5)].Humus-like substances accounted for the largest proportion of total components(60.12%),significantly higher than humic acid-like and protein-like substances,while humic acid-like substances accounted for the smallest proportion(11.25%)of total components.C1,C2,and C3 had a significant positive correlation,while C5 was significantly negatively correlated with the other four fluorescent components.There was a significant correlation between the fivekinds of fluorescent components and the fluorescence index,respectively,with only C5 showing a positive correlation with the fluorescence index.The forest soil heavy metal contentswere significant differences in the spatial distribution,with significant positive correlations between As and Cr,Cu and Zn,Ni and Zn,Hg and Pb,and significant negative correlations between Hg and Cu,Ni and Zn,Cr,and Pb,respectively.The correlationsamong the three types of fluorescent substances,Cr and Pb,were not significant,but all fluorescent substances had a significant correlation with Zn.Moreover,there was a significant correlation between humus-like substances and Cu and Hg;humic acid-like substances and Cu,Hg,and Ni;protein-like substances and Ni,respectively.The results of this study provide basic data for monitoring the forest soil environment of Maolan'gou National Nature Reserve and provide references for the assessment of heavy metal pollution in the soil of typical coniferous and broad-leaved mixed forests in Xiaoxing'anling.
作者
史传奇
李艳
胡钰
孟令波
金梁
于少鹏
SHI Chuan-qi;LI Yan;HU Yu;MENG Ling-bo;JIN Liang;YU Shao-peng(Heilongjiang Province Key Laboratory of Cold Region Wetland Ecology and Environment Research,Harbin University,Harbin 150086,China;Institute of Plant Nutrition,Resources and Environment,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China;College of Resource and Environment,Northeast Agricultural University,Harbin 150038,China)
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2024年第10期2884-2889,共6页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(32271657)
中国与联合国开发计划署合作水资源管理项目(cpr/21/401)资助。
关键词
三维荧光光谱
溶解性有机质
荧光组分
重金属
Three-dimensional fluorescence spectroscopy
Dissolved organic matter
Fluorescence component
Heavy metal
