温带森林土壤渗漏液DOM含量与组分及光谱特性  

Concentrations and Components of Dissolved Organic Matter and Its Spectral Characteristics in Soil Leachates from a Temperate Forest Stand

作　　者：苗敏 吴浩浩 韩琳[1] 傅平青[2] 徐星凯[2,3] MIAO Min;WU Haohao;HAN Lin;FU Pingqing;XU Xingkai(College of Atmospheric Science,Chengdu University of Information Technology,Chengdu 610225,China;State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China;Department of Atmospheric Chemistry and Environmental Science,College of Earth Science,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]成都信息工程大学大气科学学院,四川成都610225 [2]中国科学院大气物理研究所大气边界层物理和大气化学国家重点实验室,北京100029 [3]中国科学院大学地球科学学院大气化学与环境科学系,北京100049

出　　处：《环境科学与技术》2018年第12期169-178,共10页Environmental Science & Technology

基　　金：国家自然科学基金(41275166;41575154;41775163)

摘　　要：文章利用连续流动分析和三维荧光光谱技术,研究了不同形态[(NH_4)_2SO_4、NH_4Cl和KNO_3]和剂量(22.5和45 kgN/(hm^2·a)模拟氮沉降、碳添加(葡萄糖,64 kgC/(hm^2·a)以及去除凋落物处理9 a后温带森林实验样地,在融化末期(5月)和植被生长旺期(7月)森林土壤渗漏液溶解性有机质(DOM)含量与组分及其光谱特性的变化规律。对实验所有处理森林土壤渗漏液三维荧光光谱进行平行因子分析,得到DOM的3个荧光组分:富里酸类DOM、腐殖酸类DOM和蛋白类DOM。在不考虑实验处理的影响,与融化末期相比,植被生长旺期森林土壤渗漏液溶解性有机碳(DOC)及其生物可降解(BDOC)含量均显著地增加,DOM中蛋白类组分贡献率较低、腐殖化程度较高、生物源贡献较少而陆源贡献较大。长期碳氮干扰对融化末期森林土壤渗漏液DOC含量及其生物可降解性均无显著影响。长期去除凋落物和碳添加处理降低了植被生长旺期森林土壤渗漏液DOC和BDOC含量。长期模拟氮沉降对森林土壤渗漏液DOM 3种组分的含量和贡献率的影响与外源氮的形态和剂量有关。该研究显示长期碳氮干扰条件下,在上述2种不同时期森林土壤渗漏液DOM的生物可降解性与荧光组分及相关参数所反映的DOM活性具有较高的一致性。实验结果为深入研究森林土壤渗漏液DOM含量和组分及其稳定性的影响因素提供参考。By using continuous flow analysis and three-dimensional fluorescence spectroscopy technology, the changes in concentrations, compositions and spectral characteristics of dissolved organic matter(DOM) in forest soil leachates during the most productive period of vegetation growth(July) and the end of spring thaw(May) were studied. The soil leachate samples were collected from a long-term temperate forest experiment field which experienced nine-year anthropogenic treatments, including different forms [(NH4)2 SO4, NH4Cl and KNO3)] and doses(22.5 and 45 kgN/(hm2·a) of simulated nitrogen(N) deposition, carbon(C) addition(glucose, 64 kg C/(hm2·a) and litter removal. By parallel factor analysis for the three-dimensional fluorescence spectroscopy of all the forest soil leachates, three fluorescence components of DOM were obtained, which included fulvic acid-like component, humic-like component and protein-like component. Without considering the influences of the experimental treatments, the concentrations of dissolved organic carbon(DOC) and biodegradable DOC(BDOC), humification degree and terrestrial contribution of DOM were significantly higher, but the contribution of protein-like component and biological sources of DOM were significantly lower in forest soil leachates during the most productive period of vegetation growth compared with those during the end of spring thaw. The long-term C and N addition had no significant effect on theconcentration and biodegradability of DOC in the soil leachates during the end of spring thaw. The long-term litter removal and C addition treatment reduced DOC and BDOC concentrations in the soil leachates during the most productive period of vegetation growth. The effects of long-term simulated N deposition on the concentrations and contribution of DOM components in forest soil leachates were related to the forms and doses of exogenous N. In this study, the DOM biodegradability in forest soil leachates was highly consistent with its activity under the two different periods upon long-

关 键 词：森林土壤渗漏液 氮沉降 凋落物 溶解性有机质 三维荧光光谱-平行因子分析 

分 类 号：X826[环境科学与工程—环境工程]