Rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the Siberian lowland tundra
Thermokarst features, such as thaw ponds, are hotspots for methane emissions in warming lowland tundra. Presently we lack quantitative knowledge on the formation rates of formation of thaw ponds and subsequent vegetation succession, necessary to determine their net contribution to greenhouse gas emi...
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ftdanspts:doi:10.17026/dans-29c-tdq5 2024-09-15T17:59:52+00:00 Rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the Siberian lowland tundra R.I. Magnusson 2019-01-01 https://doi.org/10.17026/dans-29c-tdq5 English eng DANS Data Station Phys-Tech Sciences https://doi.org/10.17026/dans-29c-tdq5 Field measurements and dendrochronological analysis of Betula nana shrubs, digitized polygon shapefiles based on very high resolution satellite imagery (GeoEye1, August 2010; WorldView2, July 2015; WorldView2, July 2017; WorldView2; July 2018). Agricultural Sciences thermokarst tundra arctic siberia thaw pond vegetation succession 2019 ftdanspts https://doi.org/10.17026/dans-29c-tdq5 2024-07-26T14:05:20Z Thermokarst features, such as thaw ponds, are hotspots for methane emissions in warming lowland tundra. Presently we lack quantitative knowledge on the formation rates of formation of thaw ponds and subsequent vegetation succession, necessary to determine their net contribution to greenhouse gas emissions. This study set out to identify development trajectories and formation rates approximate rates of of small-scale (< 1 km2) arctic thaw ponds in north-eastern Siberia. We selected 40 ponds of different age classes based on a time-series of satellite images and measured vegetation composition, microtopography, water table and active layer thicknessthaw depth in the field and measured age of recruiting colonizing shrubs in thaw ponds using dendrochronology. We found that young thaw ponds are characterised by dead shrubs, while older ponds show rapid paludification through colonization bycontain mostly sedges and Sphagnum moss. While dead shrubs and open water are associated with permafrost degradation (lower surface elevation, high active layer thicknesslarger thaw depth), sites with sedge and in particular Sphagnum display indications of permafrost recovery. Recruitment of Betula nana on Sphagnum carpets in ponds indicates a potential recovery towards shrub dominated vegetation, although it remains unclear if and on what timescale this occurs. Our results suggest that thaw ponds display potentially cyclic vegetation succession associated with permafrost degradation and recovery. Thaw pond formation and initial colonization by sedges can occur on subdecadal timescales, which is relatively fast compared to rates known for ice wedge degradation (subdecadal to century-scale). The rates of formation and recovery of small-scale thaw ponds have implications for the greening/browning dynamics and carbon balance of this ecosystem. Additional information is in the README file Other/Unknown Material Betula nana Ice permafrost Thermokarst Tundra wedge* Siberia DANS Data Station Physical and Technical Sciences (Data Archiving and Networked Services) |
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Open Polar |
collection |
DANS Data Station Physical and Technical Sciences (Data Archiving and Networked Services) |
op_collection_id |
ftdanspts |
language |
English |
topic |
Agricultural Sciences thermokarst tundra arctic siberia thaw pond vegetation succession |
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Agricultural Sciences thermokarst tundra arctic siberia thaw pond vegetation succession R.I. Magnusson Rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the Siberian lowland tundra |
topic_facet |
Agricultural Sciences thermokarst tundra arctic siberia thaw pond vegetation succession |
description |
Thermokarst features, such as thaw ponds, are hotspots for methane emissions in warming lowland tundra. Presently we lack quantitative knowledge on the formation rates of formation of thaw ponds and subsequent vegetation succession, necessary to determine their net contribution to greenhouse gas emissions. This study set out to identify development trajectories and formation rates approximate rates of of small-scale (< 1 km2) arctic thaw ponds in north-eastern Siberia. We selected 40 ponds of different age classes based on a time-series of satellite images and measured vegetation composition, microtopography, water table and active layer thicknessthaw depth in the field and measured age of recruiting colonizing shrubs in thaw ponds using dendrochronology. We found that young thaw ponds are characterised by dead shrubs, while older ponds show rapid paludification through colonization bycontain mostly sedges and Sphagnum moss. While dead shrubs and open water are associated with permafrost degradation (lower surface elevation, high active layer thicknesslarger thaw depth), sites with sedge and in particular Sphagnum display indications of permafrost recovery. Recruitment of Betula nana on Sphagnum carpets in ponds indicates a potential recovery towards shrub dominated vegetation, although it remains unclear if and on what timescale this occurs. Our results suggest that thaw ponds display potentially cyclic vegetation succession associated with permafrost degradation and recovery. Thaw pond formation and initial colonization by sedges can occur on subdecadal timescales, which is relatively fast compared to rates known for ice wedge degradation (subdecadal to century-scale). The rates of formation and recovery of small-scale thaw ponds have implications for the greening/browning dynamics and carbon balance of this ecosystem. Additional information is in the README file |
author |
R.I. Magnusson |
author_facet |
R.I. Magnusson |
author_sort |
R.I. Magnusson |
title |
Rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the Siberian lowland tundra |
title_short |
Rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the Siberian lowland tundra |
title_full |
Rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the Siberian lowland tundra |
title_fullStr |
Rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the Siberian lowland tundra |
title_full_unstemmed |
Rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the Siberian lowland tundra |
title_sort |
rapid vegetation succession and coupled permafrost dynamics in arctic thaw ponds in the siberian lowland tundra |
publisher |
DANS Data Station Phys-Tech Sciences |
publishDate |
2019 |
url |
https://doi.org/10.17026/dans-29c-tdq5 |
genre |
Betula nana Ice permafrost Thermokarst Tundra wedge* Siberia |
genre_facet |
Betula nana Ice permafrost Thermokarst Tundra wedge* Siberia |
op_source |
Field measurements and dendrochronological analysis of Betula nana shrubs, digitized polygon shapefiles based on very high resolution satellite imagery (GeoEye1, August 2010; WorldView2, July 2015; WorldView2, July 2017; WorldView2; July 2018). |
op_relation |
https://doi.org/10.17026/dans-29c-tdq5 |
op_doi |
https://doi.org/10.17026/dans-29c-tdq5 |
_version_ |
1810436986126729216 |