Glacier Outflow Dissolved Organic Matter as a Window Into Seasonally Changing Carbon Sources: Leverett Glacier, Greenland

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F20%3A10420527" target="_blank" >RIV/00216208:11310/20:10420527 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=vutr.ahZu1" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=vutr.ahZu1</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2019JG005161" target="_blank" >10.1029/2019JG005161</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Glacier Outflow Dissolved Organic Matter as a Window Into Seasonally Changing Carbon Sources: Leverett Glacier, Greenland

Popis výsledku v původním jazyce

The Greenland Ice Sheet is losing mass at a remarkable rate as a result of climatic warming. This mass loss coincides with the export of dissolved organic matter (DOM) in glacial meltwaters. However, little is known about how the source and composition of exported DOM changes over the melt season, which is key for understanding its fate in downstream ecosystems. Over the 2015 ablation season, we sampled the outflow of Leverett Glacier, a large land-terminating glacier of the Greenland Ice Sheet. Dissolved organic carbon (DOC) concentrations and DOM fluorescence were analyzed to assess the evolution of DOM sources over the course of the melt season. DOC concentrations and red-shifted fluorescence were highly associated (R-2 &gt; 0.95) and suggest terrestrial inputs from overridden soils dominated DOM early season inputs before progressive dilution with increasing discharge. During the outburst period, supraglacial drainage events disrupted the subglacial drainage system and introduced dominant protein-like fluorescence signatures not observed in basal flow. These results suggest that subglacial hydrology and changing water sources influence exported DOC concentration and DOM composition, and these sources were differentiated using fluorescence characteristics. Red-shifted fluorescence components were robust proxies for DOC concentration. Finally, the majority of DOM flux, which occurs during the outburst and postoutburst periods, was characterized by protein-like fluorescence from supraglacial and potentially subglacial microbial sources. As protein-like fluorescence is linked to the bioavailability of DOM, the observed changes likely reflect seasonal variations in the impact of glacial inputs on secondary production in downstream ecosystems due to shifting hydrologic regimes.

Název v anglickém jazyce

Glacier Outflow Dissolved Organic Matter as a Window Into Seasonally Changing Carbon Sources: Leverett Glacier, Greenland

Popis výsledku anglicky

The Greenland Ice Sheet is losing mass at a remarkable rate as a result of climatic warming. This mass loss coincides with the export of dissolved organic matter (DOM) in glacial meltwaters. However, little is known about how the source and composition of exported DOM changes over the melt season, which is key for understanding its fate in downstream ecosystems. Over the 2015 ablation season, we sampled the outflow of Leverett Glacier, a large land-terminating glacier of the Greenland Ice Sheet. Dissolved organic carbon (DOC) concentrations and DOM fluorescence were analyzed to assess the evolution of DOM sources over the course of the melt season. DOC concentrations and red-shifted fluorescence were highly associated (R-2 &gt; 0.95) and suggest terrestrial inputs from overridden soils dominated DOM early season inputs before progressive dilution with increasing discharge. During the outburst period, supraglacial drainage events disrupted the subglacial drainage system and introduced dominant protein-like fluorescence signatures not observed in basal flow. These results suggest that subglacial hydrology and changing water sources influence exported DOC concentration and DOM composition, and these sources were differentiated using fluorescence characteristics. Red-shifted fluorescence components were robust proxies for DOC concentration. Finally, the majority of DOM flux, which occurs during the outburst and postoutburst periods, was characterized by protein-like fluorescence from supraglacial and potentially subglacial microbial sources. As protein-like fluorescence is linked to the bioavailability of DOM, the observed changes likely reflect seasonal variations in the impact of glacial inputs on secondary production in downstream ecosystems due to shifting hydrologic regimes.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/GJ15-17346Y" target="_blank" >GJ15-17346Y: Světlé zítřky subglaciálních ekosystémů: Dopady odledňování na mikrobiální aktivitu a koloběh uhlíku pod ledovci</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Geophysical Research-Biogeosciences

ISSN

2169-8953

e-ISSN

—

Svazek periodika

125

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

16

Strana od-do

—

Kód UT WoS článku

000535659000002

EID výsledku v databázi Scopus

2-s2.0-85091026394