Dissolved organic matter characterization in soils and streams in a small coastal low-Arctic catchment

Abstract δ 13 C DOC, optical properties and source apportionment) and bioavailability (incubations; optical indices such as slope ratio, S r T mg DOC g - 1 soil OC) generally increases with depth but shows a large variability near the transition zone (around the permafrost table). Active-layer porewater DOC generally is more labile than permafrost DOC, due to various reasons (heterogeneity, presence of a paleo-active-layer and sampling strategies). Despite these differences, the very long transport times of porewater DOC indicate that substantial processing occurs in soils prior to release into streams. Within the stream, DOC strongly dominates over POC, illustrated by DOC/POC ratios around 50, yet storm events decrease that ratio to around 5. Source apportionment of stream DOC suggests a contribution of around 50 % from permafrost/deep-active-layer OC, which contrasts with patterns observed in large Arctic rivers (12 ± d monitoring period demonstrated temporal DOC patterns on multiple scales (i.e., diurnal patterns, storm events and longer-term trends), underlining the need for high-resolution long-term monitoring. First estimates of Black Creek annual DOC (8.2 ± t DOC yr - 1) and POC (0.21 ± t yr - 1) export allowed us to make a rough upscaling towards the entire Yukon Coastal Plain (34.51 ± kt DOC yr - 1 and 8.93 ± kt POC yr - 1). Rising Arctic temperatures, increases in runoff, soil organic matter (OM) leaching, permafrost thawing and primary production are likely to increase the net lateral OC flux. Consequently, altered lateral fluxes may have strong impacts on Arctic aquatic ecosystems and Arctic carbon cycling.

Angaben zum Objekt

• Standort: Deutsche Nationalbibliothek Frankfurt am Main
• Umfang: Online-Ressource
• Sprache: Englisch

Verweise und Beziehungen

• Erschienen in: Dissolved organic matter characterization in soils and streams in a small coastal low-Arctic catchment ; volume:19 ; number:12 ; year:2022 ; pages:3073-3097 ; extent:25 ; Biogeosciences ; 19, Heft 12 (2022), 3073-3097 (gesamt 25)

Beteiligte, Orts- und Zeitangaben

• Urheber: Speetjens, Niek Jesse ; Tanski, George ; Martin, Victoria ; Wagner, Julia ; Richter, Andreas ; Hugelius, Gustaf ; Boucher, Chris ; Lodi, Rachele ; Knoblauch, Christian ; Koch, Boris ; Wünsch, Urban ; Lantuit, Hugues ; Vonk, Jorien E.

Weitere Informationen

• DOI: 10.5194/bg-19-3073-2022
• URN: urn:nbn:de:101:1-2022070705222891661331
• Rechteinformation: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Letzte Aktualisierung: 15.08.2025, 07:30 MESZ