Optical properties of dissolved organic matter (DOM): Effects of biological and photolytic degradation

Limnology and Oceanography
By: , and 

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Abstract

Advances in spectroscopic techniques have led to an increase in the use of optical properties (absorbance and fluorescence) to assess dissolved organic matter (DOM) composition and infer sources and processing. However, little information is available to assess the impact of biological and photolytic processing on the optical properties of original DOM source materials. We measured changes in commonly used optical properties and indices in DOM leached from peat soil, plants, and algae following biological and photochemical degradation to determine whether they provide unique signatures that can be linked to original DOM source. Changes in individual optical parameters varied by source material and process, with biodegradation and photodegradation often causing values to shift in opposite directions. Although values for different source materials overlapped at the end of the 111-day lab experiment, multivariate statistical analyses showed that unique optical signatures could be linked to original DOM source material even after degradation, with 17 optical properties determined by discriminant analysis to be significant (p<0.05) in distinguishing between DOM source and environmental processing. These results demonstrate that inferring the source material from optical properties is possible when parameters are evaluated in combination even after extensive biological and photochemical alteration.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Optical properties of dissolved organic matter (DOM): Effects of biological and photolytic degradation
Series title Limnology and Oceanography
DOI 10.1002/lno.10270
Volume 61
Issue 3
Year Published 2016
Language English
Publisher Association for the Sciences of Limnology and Oceanography
Contributing office(s) California Water Science Center
Description 18 p.
First page 1015
Last page 1032
Online Only (Y/N) N
Additional Online Files (Y/N) N