Role of the photo-Fenton reaction in the production of hydroxyl radicals and photobleaching of colored dissolved organic matter in a coastal river of the southeastern United States

2003 ◽  
Vol 65 (4) ◽  
pp. 402-414 ◽  
Author(s):  
Emily M. White ◽  
Pamela P. Vaughan ◽  
Richard G. Zepp
Keyword(s):  
United States ◽  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Hydroxyl Radicals ◽  
Fenton Reaction ◽  
Southeastern United States ◽  
Colored Dissolved Organic Matter ◽  
Coastal River

Photooxidation and Its Effects on the Carboxyl Content of Dissolved Organic Matter in Two Coastal Rivers in the Southeastern United States

2004 ◽  
Vol 38 (15) ◽  
pp. 4113-4119 ◽  
Author(s):  
Huixiang Xie ◽  
Oliver C. Zafiriou ◽  
Wei-Jun Cai ◽  
Richard G. Zepp ◽  
Yongchen Wang
Keyword(s):  
United States ◽  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Southeastern United States ◽  
Carboxyl Content ◽  
Coastal Rivers

scholarly journals DOM degradation by light and microbes along the Yukon River-coastal ocean continuum

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Brice K. Grunert ◽  
Maria Tzortziou ◽  
Patrick Neale ◽  
Alana Menendez ◽  
Peter Hernes
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Salinity Gradient ◽  
Coastal Ocean ◽  
Interactive Effects ◽  
The Arctic ◽  
Yukon River ◽  
Spring Freshet ◽  
Dom Composition

AbstractThe Arctic is experiencing rapid warming, resulting in fundamental shifts in hydrologic connectivity and carbon cycling. Dissolved organic matter (DOM) is a significant component of the Arctic and global carbon cycle, and significant perturbations to DOM cycling are expected with Arctic warming. The impact of photochemical and microbial degradation, and their interactive effects, on DOM composition and remineralization have been documented in Arctic soils and rivers. However, the role of microbes, sunlight and their interactions on Arctic DOM alteration and remineralization in the coastal ocean has not been considered, particularly during the spring freshet when DOM loads are high, photoexposure can be quite limited and residence time within river networks is low. Here, we collected DOM samples along a salinity gradient in the Yukon River delta, plume and coastal ocean during peak river discharge immediately after spring freshet and explored the role of UV exposure, microbial transformations and interactive effects on DOM quantity and composition. Our results show: (1) photochemical alteration of DOM significantly shifts processing pathways of terrestrial DOM, including increasing relative humification of DOM by microbes by > 10%; (2) microbes produce humic-like material that is not optically distinguishable from terrestrial humics; and (3) size-fractionation of the microbial community indicates a size-dependent role for DOM remineralization and humification of DOM observed through modeled PARAFAC components of fluorescent DOM, either through direct or community effects. Field observations indicate apparent conservative mixing along the salinity gradient; however, changing photochemical and microbial alteration of DOM with increasing salinity indicate changing DOM composition likely due to microbial activity. Finally, our findings show potential for rapid transformation of DOM in the coastal ocean from photochemical and microbial alteration, with microbes responsible for the majority of dissolved organic matter remineralization.

Coastal conduit in southwestern Hudson Bay (Canada) in summer: Rapid transit of freshwater and significant loss of colored dissolved organic matter

2009 ◽  
Vol 114 (C8) ◽  
Author(s):  
Mats A. Granskog ◽  
Robie W. Macdonald ◽  
Zou Zou A. Kuzyk ◽  
Simon Senneville ◽  
Christopher-John Mundy ◽  
...  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Significant Loss ◽  
Hudson Bay ◽  
Rapid Transit ◽  
Colored Dissolved Organic Matter
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