Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways
Permafrost-affected soils around the Arctic Ocean contain a large reservoir of organic matter including nitrogen, which partly reaches the riverine system after thawing, degradation and erosion of permafrost. After mobilization, reactive nitrogen in form of dissolved organic nitrogen (DON) ordissolv...
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ftawi:oai:epic.awi.de:57856 2024-09-15T17:54:14+00:00 Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways Sanders, Tina Fiencke, Claudia Juhls, Bennet Ogneva, Olga Strauss, Jens Schulz, Gesa Tuerena, Robyn Wetterich, Sebastian Dähnke, Kirstin 2023-06-22 application/pdf https://epic.awi.de/id/eprint/57856/ https://epic.awi.de/id/eprint/57856/1/Sanders_EUCOP2023-ABSTRACTS-2.pdf https://hdl.handle.net/10013/epic.b683d057-4819-4481-abe0-04f4d6b82604 unknown https://epic.awi.de/id/eprint/57856/1/Sanders_EUCOP2023-ABSTRACTS-2.pdf Sanders, T. , Fiencke, C. , Juhls, B. , Ogneva, O. , Strauss, J. orcid:0000-0003-4678-4982 , Schulz, G. , Tuerena, R. , Wetterich, S. and Dähnke, K. (2023) Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways hdl:10013/epic.b683d057-4819-4481-abe0-04f4d6b82604 EPIC3 Conference NonPeerReviewed 2023 ftawi 2024-06-24T04:30:12Z Permafrost-affected soils around the Arctic Ocean contain a large reservoir of organic matter including nitrogen, which partly reaches the riverine system after thawing, degradation and erosion of permafrost. After mobilization, reactive nitrogen in form of dissolved organic nitrogen (DON) ordissolved inorganic nitrogen (DIN: ammonium and nitrate) is either used for primary production, microbial turnover and/or is transported to coastal waters where it serves as a key source of nutrition for the marine food web. In this study, we have followed the nitrogen released from permafrost soil via the Lena River into the Laptev Sea and used the natural abundance of 15N stable isotopes to identify sources, sinks and processes. Therefore, we have investigated different soil. We present a comprehensive data set from two transect cruises (03/08 2019) through the delta, and the outcome of a monitoring program (2018 - 2021) at Samoylov Island in the central delta. High-frequency monitoring and cruise data shows that the nitrogen transported from the river to the Laptev Sea was dominated by DON and nitrate, which occurred in similar amounts of approx. 10 μmol L–1 in the river water. The nitrate concentration decreased during the early summer and increased from late summer throughout the winter until the spring flood. During the spring flood, the nitrogen concentration was up to ten times higher. Thus, spring floods transport approx. 20 % of the annual load of reactive nitrogen into the Laptev Sea just at the onset of the growing season. The nitrogen stable isotope values of the different nitrogen components ranged mainly between 0.5 and 4.5‰, and were subsequently enriched from the permafrost soils via suspended particulate matter/sediment and DON to nitrate, which indicate an oligotrophic ecosystem. Using a Bayesian mixing model, the stable isotope signature of nitrate suggested a strong source of atmospheric deposition during the spring flood. During the rest of the year, soils are the main source of the reactive nitrogen, ... Conference Object Arctic Ocean laptev Laptev Sea lena river permafrost Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Permafrost-affected soils around the Arctic Ocean contain a large reservoir of organic matter including nitrogen, which partly reaches the riverine system after thawing, degradation and erosion of permafrost. After mobilization, reactive nitrogen in form of dissolved organic nitrogen (DON) ordissolved inorganic nitrogen (DIN: ammonium and nitrate) is either used for primary production, microbial turnover and/or is transported to coastal waters where it serves as a key source of nutrition for the marine food web. In this study, we have followed the nitrogen released from permafrost soil via the Lena River into the Laptev Sea and used the natural abundance of 15N stable isotopes to identify sources, sinks and processes. Therefore, we have investigated different soil. We present a comprehensive data set from two transect cruises (03/08 2019) through the delta, and the outcome of a monitoring program (2018 - 2021) at Samoylov Island in the central delta. High-frequency monitoring and cruise data shows that the nitrogen transported from the river to the Laptev Sea was dominated by DON and nitrate, which occurred in similar amounts of approx. 10 μmol L–1 in the river water. The nitrate concentration decreased during the early summer and increased from late summer throughout the winter until the spring flood. During the spring flood, the nitrogen concentration was up to ten times higher. Thus, spring floods transport approx. 20 % of the annual load of reactive nitrogen into the Laptev Sea just at the onset of the growing season. The nitrogen stable isotope values of the different nitrogen components ranged mainly between 0.5 and 4.5‰, and were subsequently enriched from the permafrost soils via suspended particulate matter/sediment and DON to nitrate, which indicate an oligotrophic ecosystem. Using a Bayesian mixing model, the stable isotope signature of nitrate suggested a strong source of atmospheric deposition during the spring flood. During the rest of the year, soils are the main source of the reactive nitrogen, ... |
format |
Conference Object |
author |
Sanders, Tina Fiencke, Claudia Juhls, Bennet Ogneva, Olga Strauss, Jens Schulz, Gesa Tuerena, Robyn Wetterich, Sebastian Dähnke, Kirstin |
spellingShingle |
Sanders, Tina Fiencke, Claudia Juhls, Bennet Ogneva, Olga Strauss, Jens Schulz, Gesa Tuerena, Robyn Wetterich, Sebastian Dähnke, Kirstin Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways |
author_facet |
Sanders, Tina Fiencke, Claudia Juhls, Bennet Ogneva, Olga Strauss, Jens Schulz, Gesa Tuerena, Robyn Wetterich, Sebastian Dähnke, Kirstin |
author_sort |
Sanders, Tina |
title |
Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways |
title_short |
Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways |
title_full |
Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways |
title_fullStr |
Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways |
title_full_unstemmed |
Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways |
title_sort |
permafrost land-ocean interactions: fluxes, transport processes and degradation pathways |
publishDate |
2023 |
url |
https://epic.awi.de/id/eprint/57856/ https://epic.awi.de/id/eprint/57856/1/Sanders_EUCOP2023-ABSTRACTS-2.pdf https://hdl.handle.net/10013/epic.b683d057-4819-4481-abe0-04f4d6b82604 |
genre |
Arctic Ocean laptev Laptev Sea lena river permafrost |
genre_facet |
Arctic Ocean laptev Laptev Sea lena river permafrost |
op_source |
EPIC3 |
op_relation |
https://epic.awi.de/id/eprint/57856/1/Sanders_EUCOP2023-ABSTRACTS-2.pdf Sanders, T. , Fiencke, C. , Juhls, B. , Ogneva, O. , Strauss, J. orcid:0000-0003-4678-4982 , Schulz, G. , Tuerena, R. , Wetterich, S. and Dähnke, K. (2023) Permafrost land-ocean interactions: fluxes, transport processes and degradation pathways hdl:10013/epic.b683d057-4819-4481-abe0-04f4d6b82604 |
_version_ |
1810430481683972096 |