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Title: Changes in light absorption and composition of chromophoric marine-dissolved organic matter across a microbial bloom
Marine chromophoric dissolved organic matter (m-CDOM) mediates many vital photochemical processes at the ocean's surface. Isolating m-CDOM within the chemical complexity of marine dissolved organic matter has remained an analytical challenge. The SeaSCAPE campaign, a large-scale mesocosm experiment, provided a unique opportunity to probe the in situ production of m-CDOM across phytoplankton and microbial blooms. Results from mass spectrometry coupled with UV-VIS spectroscopy reveal production of a chemodiverse set of compounds well-correlated with increases in absorbance after a bacterial bloom, indicative of autochthonous m-CDOM production. Notably, many of the absorbing compounds were found to be enriched in nitrogen, which may be essential to chromophore function. From these results, quinoids, porphyrins, flavones, and amide-like compounds were identified via structural analysis and may serve as important photosensitizers in the marine boundary layer. Overall, this study demonstrates a step forward in identifying and characterizing m-CDOM using temporal mesocosm data and integrated UV-VIS spectroscopy and mass spectrometry analyses.  more » « less
Award ID(s):
1801971
PAR ID:
10397572
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Environmental Science: Processes & Impacts
Volume:
24
Issue:
10
ISSN:
2050-7887
Page Range / eLocation ID:
1923 to 1933
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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