Document generated on 10/02/2021 1:43 a.m. Géographie physique et Quaternaire Holocene Development and Permafrost History of the Usinsk Mire, Northeast European Russia Évolution à l’Holocène et histoire du pergélisol de la tourbière d'Usinsk, au nord-est de la Russie d’Europe Развитие в голоцене и история вечной мерзлоты Усинского болота на Северо-Востоке европейской России Pirita O. Oksanen, Peter Kuhry and Rimma N. Alekseeva Volume 57, Number 2-3, 2003 Article abstract This study discusses Holocene vegetation succession, permafrost dynamics and URI: https://id.erudit.org/iderudit/011312ar peat accumulation in the Usinsk mire, located in the Pechora lowlands of DOI: https://doi.org/10.7202/011312ar Northeast European Russia. At present, the area is situated in the extreme northern taiga subzone near the southern limit of permafrost. Reconstructions See table of contents are based on plant macrofossil analysis, physico-chemical analysis and AMS (accelerator mass spectrometry) radiocarbon dating of two peat profiles investigated in detail. Additional information is available from seven other 14 Publisher(s) sites. Organic accumulation started at ca. 11 350 BP ( C yrs). Terrestrialization of ponds was the most common pathway for mire initiation. During a large Les Presses de l'Université de Montréal part of their history, the sites have been Cyperaceae-dominated fens. A change into Sphagnum-dominated ecosystems is recorded at 3700-3000 BP. Permafrost ISSN became established around 2300 BP, although first signs of embryonic palsa formation can be tentatively traced back to about 2900 BP. Palsas and peat 0705-7199 (print) plateaus have experienced several periods of freezing and entire or partial 1492-143X (digital) thawing. The extant permafrost stages are young. The long-term carbon accumulation rate in the investigated sites is 19 g/m2/yr. The average rate of Explore this journal carbon accumulation in the dynamic permafrost stage is 23 g/m2/yr. Cite this article Oksanen, P. O., Kuhry, P. & Alekseeva, R. N. (2003). Holocene Development and Permafrost History of the Usinsk Mire, Northeast European Russia. Géographie physique et Quaternaire, 57(2-3), 169–187. https://doi.org/10.7202/011312ar Tous droits réservés © Les Presses de l'Université de Montréal, 2005 This document is protected by copyright law. Use of the services of Érudit (including reproduction) is subject to its terms and conditions, which can be viewed online. https://apropos.erudit.org/en/users/policy-on-use/ This article is disseminated and preserved by Érudit. Érudit is a non-profit inter-university consortium of the Université de Montréal, Université Laval, and the Université du Québec à Montréal. Its mission is to promote and disseminate research. https://www.erudit.org/en/ GPQ_57-2-3.qxd 20/06/05 22:54 Page 169 Géographie physique et Quaternaire, 2003, vol. 57, nos 2-3, p. 169-187, 6 fig., 3 tabl. HOLOCENE DEVELOPMENT AND PERMAFROST HISTORY OF THE USINSK MIRE, NORTHEAST EUROPEAN RUSSIA Pirita O. OKSANEN*, Peter KUHRY and Rimma N. ALEKSEEVA; first and second authors: Arctic Centre, University of Lapland, P.O. Box 122, 96101 Rovaniemi, Finland; third author: Institute of Biology, Komi Science Centre, Ural Branch, Russian Academy of Sciences, Kommunisticheskaya Street 26, 167610 Syktyvkar, Russia. ABSTRACT This study discusses Holocene RÉSUMÉ Évolution à l’Holocène et histoire РЕФЕРАТ Развитие в голоцене и история vegetation succession, permafrost dynamics du pergélisol de la tourbière d'Usinsk, au вечной мерзлоты Усинского болота на and peat accumulation in the Usinsk mire, nord-est de la Russie d’Europe. Cette étude Северо-Востоке европейской России. located in the Pechora lowlands of Northeast discute de la succession de la végétation, de Изучены развитие растительности в European Russia. At present, the area is la dynamique du pergélisol et de l'accumula- голоцене, динамика вечной мерзлоты и situated in the extreme northern taiga sub- tion de la tourbe à l'Holocène dans la tour- аккумуляция торфа на Усинском болоте, zone near the southern limit of permafrost. bière d'Usinsk, située dans les basses terres которое находится на Печорской равнине Reconstructions are based on plant macro- de Pechora, au nord-est de la Russie Северо-Востока европейской Россий. В fossil analysis, physico-chemical analysis and d’Europe. La région se trouve dans l'extrême настоящее время район расположен в AMS (accelerator mass spectrometry) radio- nord de la taïga actuelle, près de la limite крайнесеверной тайге вближи южной carbon dating of two peat profiles investigated méridionale du pergélisol. Les reconstitutions границы вечной мерзлоты. Реконструкция in detail. Additional information is available sont fondées sur l'analyse macrofossile des основана на анализе растительных from seven other sites. Organic accumulation plantes, l'analyse physico-chimique et les остатков, физико-химического анализа и started at ca. 11 350 BP (14C yrs). Terres- dates au radiocarbone déterminées par spec- радиоуглеродной датировки (АМS) двух trialization of ponds was the most common trométrie de masse à l’aide d’un accélérateur подробно изученных профилей торфа. pathway for mire initiation. During a large de particules (SMA) de deux profils de tourbe Также получена информация из семи part of their history, the sites have been étudiés en détail. De l'information addition- других точек. Органическая аккумуляция Cyperaceae-dominated fens. A change into nelle provient de sept autres sites. L'accu- началась примерно в 11 350 ВP (14C годы). Sphagnum-dominated ecosystems is recor- mulation de matière organique a commencé Заболачивание как правило пройсходило ded at 3700-3000 BP. Permafrost became vers 11 350 BP (années 14C). L’accumulation путем зарастания озер. На протяжении established around 2300 BP, although first de tourbe dans les étangs était alors le point большей части их развития в signs of embryonic palsa formation can be de départ le plus habituel des tourbières. растительности изученных болотных tentatively traced back to about 2900 BP. Pendant une grande partie de leur formation, участков преобладало семейство Palsas and peat plateaus have experienced ces sites ont été des marais dominés par les Cyperaceae. Изменение в преобладании several periods of freezing and entire or par- Cyperaceae. La transition vers des écosys- Sphagnum отмечено в 3700-3000 ВP. tial thawing. The extant permafrost stages are tèmes dominés par les Sphagnum est enre- Вечная мерзлота сформировалась young. The long-term carbon accumulation gistrée entre 3700 et 3000 BP. Le pergélisol в 2300 ВP, хотя первые признаки rate in the investigated sites is 19 g/m2/yr. The s'est établi vers 2300 BP, bien que des signes формации эмбрионального мерзлотного average rate of carbon accumulation in the de formation embryonnaire de palses soient бугра можно проследить в 2900 ВP. dynamic permafrost stage is 23 g/m2/yr. déjà observables vers 2900 BP. Les palses Мерзлотные бугры проходили многие ont connu plusieurs épisodes de gel et de периоды замерзания и полного или dégel complet ou partiel. Les couches de per- частичного таяния. Существующие в gélisol actuellement observables sont d'ori- настоящее время мерзлотные фазы gine récente. Le taux d'accumulation du car- молодые. Долгосрочная скорость bone à long terme dans les sites étudiés est аккумуляции угля на изученных участках de 19 g/m2/an. Le taux moyen d'accumula- 19 гр/м2/г. Средняя скорость аккумуляции tion du pergélisol en phase active est в динамичной фазе вечной мерзлоты de 23 g/m2/an. 23 гр/м2/г. Manuscrit reçu le 28 février 2003 ; manuscrit révisé accepté le 23 octobre 2003 (publié le 3e trimestre 2005) * E-mail address: [email protected] _57-2-3.qxd 31/08/05 16:18 Page 170 170 P.O. OKSANEN, P.KUHRY and R. N. ALEKSEEVA INTRODUCTION but P’yavchenko (1955) used pollen stratigraphy for indirect dating of permafrost occurrence. In the southernmost regions of its distribution, like in the northern taiga of European Russia, permafrost occurrence is Plant macrofossil studies with radiocarbon dates from mires restricted to mires.Typical permafrost landforms are palsas and are reported in Oksanen et al. (1998, 2001) from the forest- peat plateaus (Andreev, 1935; P’yavchenko, 1955; Oksanen, tundra zone and in Väliranta et al. (2003) from the tundra zone. 2002). These landforms consist of frozen peat/mineral soil and The same methods used in these previous studies are applied segregated ice. Palsas are usually 1-7 m high and a few metres to the Usinsk mire, in the northern taiga, in order to compare to 100 m in diameter. Peat plateaus are larger, flat-topped ele- the age and dynamics of permafrost in different eco-climatic vated expanses of peat (van Everdingen, 1998). Aapa ridges zones. The main purpose of the present study is to date per- can in some cases be considered permafrost landforms as well, mafrost aggradation and study its effect on ecology, hydrol- maintaining frost over several years and longer (string palsas). ogy and carbon balance of the mire ecosystem. The research Permafrost degradation in mires is most noticeably observed is conducted in the central part of the Usinsk mire, where per- as collapse scars and thermokarst ponds. mafrost landforms occur. Modern vegetation is studied as a reference for the interpretation of plant macrofossil assem- Through its effect on topography and hydrology, permafrost blages. The Holocene vegetation succession and peat accu- is significant for the ecology and carbon balance of mires. An mulation rates are discussed. estimated 22% of the carbon pool in mires of the former Soviet Union is located in permafrost mires (Botch et al., 1995). A warming climate resulting in permafrost thawing and enlarged STUDY AREA wet surface areas would probably cause increased organic The Usinsk mire occupies an area of about 1 400 km2 near accumulation but also increased methane production in north- the confluence of the rivers Pechora and Usa, Komi Republic, ern taiga and tundra (Martikainen, 1996). Russia (Fig. 1). Our investigations are limited to an area of The Usinsk mire is situated at the southern limit of discon- about 12 km2 in the central part of the mire (Fig.