Seasonal and spatial variability in dissolved organic matter quantity and composition from the Yukon River basin, Alaska

Global Biogeochemical Cycles
By: , and 

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Abstract

[1] The seasonal and spatial variability of dissolved organic matter (DOM) quantity and chemical composition were investigated in the Yukon River basin of Alaska, United States, and northwestern Canada. Dissolved organic carbon (DOC), chromophoric DOM (CDOM), and dissolved lignin phenols were measured across a range of source waters and the seasonal hydrograph. Strong relationships were determined between CDOM and both DOC and lignin phenols, highlighting the potential for deriving detailed spatial and temporal distributions of DOM composition from CDOM monitoring. Maximum concentrations of measured parameters were observed during the spring flush, when DOM had a remarkably high content of aromatic vascular plant material derived from surface soil and litter layers. A larger portion of riverine DOM was attributed to vascular plant sources than previously believed by utilizing representative vegetation leachates and a soil pore water as end‐members. In combination with recent studies highlighting export of young, labile DOM during the spring flush in northern high‐latitude river systems, our results suggest riverine DOM is less degraded and more labile than previously thought with clear ramifications for its biomineralization or photo‐oxidation in marine environments.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Seasonal and spatial variability in dissolved organic matter quantity and composition from the Yukon River basin, Alaska
Series title Global Biogeochemical Cycles
DOI 10.1029/2008GB003231
Volume 22
Issue 4
Year Published 2008
Language English
Publisher AGU
Contributing office(s) Toxic Substances Hydrology Program
Description GB4002