Did long-term fire control the coniferous boreal forest composition of the northern Ural region (Komi Republic, Russia)?

• Published in: Journal of Biogeography
• Main Authors: Barhoumi, Cheima, A. Ali, Adam, Peyron, Odile, Dugerdil, Lucas, Borisova, Olga, Golubeva, Yulia, Subetto, Dmitri, Kryshen, Alexander, Drobyshev, Igor, Ryzhkova, Nina, Joannin, Sébastien
• Other Authors: Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement IRD : UR226, Institute of Geography of RAS, Russian Academy of Sciences Moscow (RAS), Herzen State Pedagogical University of Russia, Swedish University of Agricultural Sciences (SLU), Université du Québec en Abitibi-Témiscamingue (UQAT)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: charcoal; disturbances; fire history; palaeoenvironmental reconstruction; pollen; REVEALS model; Russian boreal forest; vegetation-fire interactions; [SDE.MCG]Environmental Sciences/Global Changes; [SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology; taiga
• Online Access: https://hal.archives-ouvertes.fr/hal-03023952; https://hal.archives-ouvertes.fr/hal-03023952/document; https://hal.archives-ouvertes.fr/hal-03023952/file/Barhoumi%20et%20al.,%202020%20%281%29.pdf; https://doi.org/10.1111/jbi.13922

International audience Aim Documenting past vegetation dynamics and fire-vegetation relationships at a regional scale is necessary to understand the mechanisms that control the functioning of the boreal forest, which is particularly sensitive to climate change. The objective of this study is to document these interactions in the Komi Republic during the Holocene.Location Yaksha, Vychegda river basin, Republic of Komi, Russia. Taxon Plantae, gymnosperms, angiosperms.Methods Two palaeoecological approaches are combined, based (1) on pollen (this study) and charcoal analysis (recomputed from our previous analysis) applied to cores from two peatlands and (2) on a REVEALS model (a part of the Landscape Reconstruction Algorithm "LRA") applied to six regional pollen cores in order to obtain a regional estimate of vegetation cover during the Holocene. Results The pollen diagram produced locally from Yaksha was compared with the regional vegetation cover determined by REVEALS. Taxa such asAbiessp. andPinusspp. showed differences between the two approaches, but vegetation signals remain qualitatively consistent. From 10,000 to 6,000 cal. yr BP, the forest was mainly a light taiga (composed ofPinus sylvestrisandBetulaspp.) and low fire activity was recorded. From 6,000 to 3,500 cal. yr BP, a dark taiga (composed ofPiceaspp.,Abies sibiricaandPinus sibirica) was established due to favourable climatic conditions, despite higher fire activity. From 3,500 cal. yr BP onwards, the continuous increase in fire activity allowed for a gradual return of light taiga,Betulaspp., likely reinforced by human activities. The dynamics ofPiceaspp. andAbies sp. were asynchronous between the sites. ForPiceaspp., the hypothesis of local inter-site expansion distributed along stream corridors is supported by the data. ForAbiessp., a bias in REVEALS, and in climate cooling may explain disparities between sites.Main conclusions We found evidence that in the early and mid-Holocene, vegetation dynamics were probably more influenced by climate, as ...