doi:10.16186/j.cnki.1673-9787.2020030007

Received:2020/03/03

Revised:2020/06/29

Published:2022/01/10

Comparative study of ultraviolet and fluorescence characteristics of populus tomentosa leaf litter and DOM from soil at different depths

ZHAO Li1,2,3,4, SUN Chao1,2,3, HUANG Xingyu1,2,3, LUO Shaohe1, DU Congcong1, DONG Dazhuang1, KANG Qingqing1

1.Department of Resource & Environmental Engineering， Henan Polytechnic University， Jiaozuo  454000 ， Henan， China；2.Henan Key Laboratory of Coal Green Conversion， Henan Polytechnic University， Jiaozuo  454000 ， Henan， China；3.Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region， Jiaozuo  454000 ， Henan， China；4.Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard，Xi ’ an  710077 ， Shaanxi， China

Abstract: Taking the DOM extracted from the leaf litter of Populus tomentosa and the soil at depths of 0.1 m，1 m and 50 m in Xinmi County，Zhengzhou City，Henan Province as the research object，the evolution and distribution characteristics of DOM in soil layers were compared and analysed by UV-vis and three dimensional fluorescence spectroscopy，combined with the measurement of physical and chemical indexes.The results showed that the fluorescence intensity of the fulvic acid peak was the highest in the fluorescence spectrum of DOM extracted from Populus tomentosa，while there was no obvious humic acid peak in the DOM samples extracted from the studied soil.The fluorescence intensity of aromatic protein peak and microbial byproduct peak decreased with the increase of soil depth，and there was only weak fulvic acid peak in the DOM from the soil with the depth of 50 m.The soil in the study area was alkalescent.The carbon content in the studied soil decreased gradually with the soil depth while the nitrogen content increased first and then decreased.The soild at the location of 1m from the surface might be the active layer of chemical reaction in shallow soil，with the most obvious characteristics of“autogenous source”，and the microbial activity was significantly higher than other soil layers.The studied natural organic matter degraded with rainfall and surface runoff infiltration to generate small molecular organic matter，and the migration capability of organic matter decreased with the increase of depth.There was a significant linear positive correlation between humification degree and hydrophobic component content of DOM samples from plant leaf litter and soils(R₂ = 0.998) .

Key words:dissolved organic matter;three-dimensional fluorescence spectrum;soil;leaf  litter of Populus to-mentosa

 毛白杨落叶与不同深度土中DOM的紫外与荧光特性对比研究_赵丽.pdf