Permafrost degradation and its consequences for carbon storage in soils of Interior Alaska

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Patrick Liebmann - , Leibniz Universität Hannover (LUH) (Autor:in)
  • Jiří Bárta - , University of South Bohemia (Autor:in)
  • Cordula Vogel - , Institut für Bodenkunde und Standortslehre (BOKU), Professur für Bodenressourcen und Landnutzung, Technische Universität Dresden (Autor:in)
  • Tim Urich - , Ernst-Moritz-Arndt-Universität Greifswald (Autor:in)
  • Alexander Kholodov - , University of Alaska Fairbanks (Autor:in)
  • Milan Varsadiya - , University of South Bohemia, Universität Bayreuth (Autor:in)
  • Ole Mewes - , Leibniz Universität Hannover (LUH) (Autor:in)
  • Stefan Dultz - , Leibniz Universität Hannover (LUH) (Autor:in)
  • Muhammad Waqas - , University of South Bohemia (Autor:in)
  • Haitao Wang - , Ernst-Moritz-Arndt-Universität Greifswald (Autor:in)
  • Olga Shibistova - , Leibniz Universität Hannover (LUH) (Autor:in)
  • Georg Guggenberger - , Leibniz Universität Hannover (LUH) (Autor:in)

Abstract

Permafrost soils in the northern hemisphere are known to harbor large amounts of soil organic matter (SOM). Global climate warming endangers this stable soil organic carbon (SOC) pool by triggering permafrost thaw and deepening the active layer, while at the same time progressing soil formation. But depending, e.g., on ice content or drainage, conditions in the degraded permafrost can range from water-saturated/anoxic to dry/oxic, with concomitant shifts in SOM stabilizing mechanisms. In this field study in Interior Alaska, we investigated two sites featuring degraded permafrost, one water-saturated and the other well-drained, alongside a third site with intact permafrost. Soil aggregate- and density fractions highlighted that permafrost thaw promoted macroaggregate formation, amplified by the incorporation of particulate organic matter, in topsoils of both degradation sites, thus potentially counteracting a decrease in topsoil SOC induced by the permafrost thawing. However, the subsoils were found to store notably less SOC than the intact permafrost in all fractions of both degradation sites. Our investigations revealed up to net 75% smaller SOC storage in the upper 100 cm of degraded permafrost soils as compared to the intact one, predominantly related to the subsoils, while differences between soils of wet and dry degraded landscapes were minor. This study provides evidence that the consideration of different permafrost degradation landscapes and the employment of soil fractionation techniques is a useful combination to investigate soil development and SOM stabilization processes in this sensitive ecosystem.

Details

OriginalspracheEnglisch
Seiten (von - bis)199-223
Seitenumfang25
FachzeitschriftBiogeochemistry
Jahrgang167
Ausgabenummer3
PublikationsstatusVeröffentlicht - März 2024
Peer-Review-StatusJa

Externe IDs

ORCID /0000-0002-6525-2634/work/167215333

Schlagworte

Ziele für nachhaltige Entwicklung

Schlagwörter

  • Climate change, Microbial decomposition, Permafrost thaw, Soil development, Soil fractions, Soil organic matter