{"title":"Permafrost development in northern Fennoscandian peatlands since the mid-Holocene","authors":"Marit Hichens-Bergström, A. Britta K. Sannel","doi":"10.1080/15230430.2023.2250035","DOIUrl":null,"url":null,"abstract":"Increased permafrost temperatures have been reported in the circum-Arctic, and widespread degradation of permafrost peatlands has occurred in recent decades. The timing of permafrost aggradation in these ecosystems could have implications for the soil carbon lability upon thawing, and an increased understanding of the permafrost history is therefore needed to better project future carbon feedbacks. In this study, we have conducted high-resolution plant macrofossil and geochemical analyses and accelerator mass spectrometry radiocarbon dating of active layer cores from four permafrost peatlands in northern Sweden and Norway. In the mid-Holocene, all four sites were wet fens, and at least three of them remained permafrost-free until a shift in vegetation toward bog species was recorded around 800 to 400 cal. BP, suggesting permafrost aggradation during the Little Ice Age. At one site, Karlebotn, the plant macrofossil record also indicated a period of dry bog conditions between 3300 and 2900 cal. BP, followed by a rapid shift toward species growing in waterlogged fens or open pools, suggesting that permafrost possibly was present around 3000 cal. BP but thawed and was replaced by thermokarst.","PeriodicalId":8391,"journal":{"name":"Arctic, Antarctic, and Alpine Research","volume":"18 1","pages":"0"},"PeriodicalIF":1.6000,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Arctic, Antarctic, and Alpine Research","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1080/15230430.2023.2250035","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 1
Abstract
Increased permafrost temperatures have been reported in the circum-Arctic, and widespread degradation of permafrost peatlands has occurred in recent decades. The timing of permafrost aggradation in these ecosystems could have implications for the soil carbon lability upon thawing, and an increased understanding of the permafrost history is therefore needed to better project future carbon feedbacks. In this study, we have conducted high-resolution plant macrofossil and geochemical analyses and accelerator mass spectrometry radiocarbon dating of active layer cores from four permafrost peatlands in northern Sweden and Norway. In the mid-Holocene, all four sites were wet fens, and at least three of them remained permafrost-free until a shift in vegetation toward bog species was recorded around 800 to 400 cal. BP, suggesting permafrost aggradation during the Little Ice Age. At one site, Karlebotn, the plant macrofossil record also indicated a period of dry bog conditions between 3300 and 2900 cal. BP, followed by a rapid shift toward species growing in waterlogged fens or open pools, suggesting that permafrost possibly was present around 3000 cal. BP but thawed and was replaced by thermokarst.
期刊介绍:
The mission of Arctic, Antarctic, and Alpine Research (AAAR) is to advance understanding of cold region environments by publishing original scientific research from past, present and future high-latitude and mountain regions. Rapid environmental change occurring in cold regions today highlights the global importance of this research. AAAR publishes peer-reviewed interdisciplinary papers including original research papers, short communications and review articles. Many of these papers synthesize a variety of disciplines including ecology, climatology, geomorphology, glaciology, hydrology, paleoceanography, biogeochemistry, and social science. Papers may be uni- or multidisciplinary but should have interdisciplinary appeal. Special thematic issues and proceedings are encouraged. The journal receives contributions from a diverse group of international authors from academia, government agencies, and land managers. In addition the journal publishes opinion pieces, book reviews and in memoria. AAAR is associated with the Institute of Arctic and Alpine Research (INSTAAR) the oldest active research institute at the University of Colorado Boulder.