Linking soil architecture formation with changing permafrost regime to carbon turnover in high latitude soils at multiple spatial scales

Permafrost soils store large amounts of carbon due to their permanently frozen subsoil and a lack of oxygen in the active layer, but they lack complex soil structure. With permafrost thaw more oxidative conditions and increasing soil temperature presumably enhance the build-up of more complex units of soil architecture and may counterbalance, at least partly, SOC mineralization. We aim to explore the development of mineral-organic associations and aggregates under different permafrost impact with respect to SOC stabilization. This information will be linked to environmental control factors relevant for SOC turnover at the pedon and stand scale to bridge processes occurring at the aggregate scale to larger spatial dimensions. We will combine in situ spectroscopic techniques with fractionation approaches and identify mechanisms relevant for SOC turnover at different scales by multivariate statistics and variogram analyses. From this we expect a deeper knowledge about soil architecture formation in the transition of permafrost soils to terrestrial soils and a scale-spanning mechanistic understanding of SOC cycling in permafrost regions.

Funding:

German Research Foundation (DFG)

Project team:

Alevtina Evgrafova, Prof. Dr. Sandra Spielvogel

Collaborators involved:

Ina Haase (Leibniz-Universität Hannover),
Dr. Leopold Sauheitl (Leibniz-Universität Hannover)