The role of dissolved organic matter in arctic surface waters in the photolysis of hexachlorobenzene and lindane

2012 ◽  
Vol 117 (G1) ◽  
Author(s):  
Amanda M. Grannas ◽  
Rose M. Cory ◽  
Penney L. Miller ◽  
Yu-Ping Chin ◽  
Diane M. McKnight
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Surface Waters ◽  
Arctic Surface

scholarly journals Assessing the prevalence, products, and pathways of dissolved organic matter partial photo-oxidation in arctic surface waters

2020 ◽  
Vol 22 (5) ◽  
pp. 1214-1223 ◽  
Author(s):  
Collin P. Ward ◽  
Rose M. Cory
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Surface Waters ◽  
Photochemical Oxidation ◽  
Photo Oxidation ◽  
Isotope Tracer ◽  
Arctic Surface ◽  
Tracer Experiments

Isotope tracer experiments reveal that rates of dissolved organic matter partial photochemical oxidation are considerably underestimated in arctic surface waters.

Evidence for dissolved organic matter as the primary source and sink of photochemically produced hydroxyl radical in arctic surface waters

2014 ◽  
Vol 16 (4) ◽  
pp. 807-822 ◽  
Author(s):  
Sarah E. Page ◽  
J. Robert Logan ◽  
Rose M. Cory ◽  
Kristopher McNeill
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Hydroxyl Radical ◽  
Residence Time ◽  
Surface Waters ◽  
Primary Source ◽  
The Arctic ◽  
Water Residence Time ◽  
Arctic Surface ◽  
Source And Sink

Photochemical hydroxyl radical formation decreases with increasing water residence time in a system of lakes connected by streams in the Arctic.

scholarly journals Using fluorescent dissolved organic matter to trace and distinguish the origin of Arctic surface waters

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Rafael Gonçalves-Araujo ◽  
Mats A. Granskog ◽  
Astrid Bracher ◽  
Kumiko Azetsu-Scott ◽  
Paul A. Dodd ◽  
...  
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Matter ◽  
Surface Waters ◽  
Fluorescent Dissolved Organic Matter ◽  
Arctic Surface

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.

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