Long-term ecological consequences of forest fires in the continuous permafrost zone of Siberia ...

• Main Authors: Kirdyanov, AV, Saurer, M, Siegwolf, R, Knorre, AA, Prokushkin, AS, Churakova, OV, Fonti, MV, Büntgen, U
• Format: Article in Journal/Newspaper
• Language: English
• Published: IOP Publishing 2020
• Subjects: active soil layer; boreal forest; permafrost; Siberia; stable isotopes; tree rings; wildfire
• Online Access: https://dx.doi.org/10.17863/cam.50177; https://www.repository.cam.ac.uk/handle/1810/303100

Abstract Wildfires are an important factor in controlling forest ecosystem dynamics across the circumpolar boreal zone. An improved understanding of their direct and indirect, short- to long-term impacts on vegetation cover and permafrost–vegetation coupling is particularly important to predict changes in carbon, nutrient and water cycles under projected climate warming. Here, we apply dendrochronological techniques on a multi-parameter dataset to reconstruct the effect of wildfires on tree growth and seasonal permafrost thaw depth in Central Siberia. Based on annually-resolved and absolutely dated information from 19 Gmelin larch (Larix gmelinii (Rupr.) Rupr.) trees and active soil layer thickness measurements, we find substantial stand-level die-off, as well as the removal of ground vegetation and the organic layer following a major wildfire in 1896. Reduced stem growth coincides with increased δ 13 C in the cellulose of the surviving trees during the first decade after the wildfire, when stomatal ...