Ultraviolet-Visible and Fluorescence Characteristics of Dissolved Organic Matter in the Fallen Leaves of Populus tomentosa
ZHAO Li
WANG Changyuan
YANG Zhibin
ZHEN Xiaoge
Abstract：To study the structure and type of dissolved organic matter extracted from the fallen leaves of Populus tomentosa,which are widely grown in the geothermal water recharge area in the plain of East Henan,experiments were carried out firstly to determine the optical time of extracting dissolved organic matter (DOM) from the fallen leaves of Populus tomentosa.Then the UV-Vis and three-dimensional fluorescence spectrum of DOM were measured,after which the parameters of SUVA254,A253/A203,A250/A365 and r(A/c)were calculated.The results showed that it is better to extract DOM from the fallen leaves of Populus tomenwsa after oscillating for 24h.DOC is highly linearly correlated with UV2254 indicated by the regression coefficient (R2=0.92) for the studied DOM sample,suggesting that many simple aromatic compounds containing benzene ring exist in the studied DOM and many kinds of aromatic ring substituents contain carbonyl,carboxyl,hydroxyl and lipids.Totally 4 types of fluorescence peak appear in the studied DOM,and the fluorescence intensity in the descending order are humic-like peak (including fulvic-like peak A and humic substances peak C in ultraviolet region),tyrosine aromatic protein peak T and soluble microbial metabolites peak B.At different dilution conditions of DOM samples,the validated structure and relative content of dissolved organic matter with fluorescent properties are slightly different,which are related with the factors such as the pH change of DOM samples,complex composition and disturbance of mixed fluorescent signal.
Keywords：environmental sciencedissolved organic matterultraviolet-visible spectrathree-dimensional excitation emission matrix (3D-EEM) fluorescence spectroscopyfulvic acidhumic acid
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 98-102 )