RESEARCH ARTICLE
Study of Subarctic Palsa Permafrost Under Various Thawing Conditions Based on Geophysical and Geospatial Models
Pavel Ryazantsev,
Stanislav Kutenkov,
Alexey Kabonen,
Corresponding Author
Pavel Ryazantsev
Department of Multidisciplinary Scientific Research of the Karelian Research Centre, Russian Academy of Sciences, Petrozavodsk, Russia
Correspondence:
Pavel Ryazantsev ([email protected])
Search for more papers by this authorStanislav Kutenkov
Institute of Biology of the Karelian Research Centre, Russian Academy of Sciences, Petrozavodsk, Russia
Search for more papers by this authorAlexey Kabonen
Petrozavodsk State University, Petrozavodsk, Russia
Search for more papers by this authorPavel Ryazantsev,
Stanislav Kutenkov,
Alexey Kabonen,
Corresponding Author
Pavel Ryazantsev
Department of Multidisciplinary Scientific Research of the Karelian Research Centre, Russian Academy of Sciences, Petrozavodsk, Russia
Correspondence:
Pavel Ryazantsev ([email protected])
Search for more papers by this authorStanislav Kutenkov
Institute of Biology of the Karelian Research Centre, Russian Academy of Sciences, Petrozavodsk, Russia
Search for more papers by this authorAlexey Kabonen
Petrozavodsk State University, Petrozavodsk, Russia
Search for more papers by this authorFunding: This research was funded by the Russian Science Foundation under grant No. 22-77-10055.
ABSTRACT
Subarctic palsa mires are natural indicators of the status of permafrost in its sporadic distribution zone. Estimation of the rate of their thawing can become an auxiliary indicator to predict climate shifts. The formation, growth, and degradation of palsas are dynamic processes that depend on seasonal weather fluctuations and local environmental factors. Therefore, accurate forecasts of palsas conditions and related ecosystem shifts must be based on a broad set of attributes of palsas from different regions of the Northern Hemisphere. With this in mind, we studied two palsa mires sites on the Kola Peninsula, for which no thorough descriptions were previously available. The first site, Chavanga, is at the southern limit of the permafrost zone under unfavorable climatic conditions and is a collapsing relic. The second site, Ponoy, in contrast, is within the sporadic permafrost zone with relatively cold and dry conditions. Our dataset was created by combining several methods to produce detailed spatial models of permafrost for the studied palsa mires. We used 3D ground-penetrating radar (GPR) survey, UAV-based orthophoto maps, peat thermometry, time-domain reflectometry, and manual sampling. We developed two integrated geospatial models that describe the active layer, the configuration of the palsa frozen core, and its thermal state and identify the zones of the most intense thawing. These observations revealed a significant thermal effect of the groundwater flow and its critical role in the palsas segmentation and rapid collapse. We have investigated a regulating effect of micromorphological features of palsa mounds such as heights, slope, depressions, and mire mineral bed through groundwater drainage. As a result, two new scenarios for the palsa degradation process have been developed, emphasizing the influence of environmental factors on the permafrost condition.
Conflicts of Interest
The authors declare no conflicts of interest.
Open Research
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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