On\uffe2\uff80\uff90going shrinkage of Greenland's icecap, permafrost thaw, and changes in precipitation are exposing its landscapes to erosion and remobilization of ancient organic carbon (OC) held in soils and sedimentary rocks. The fate of this OC and potential feedbacks to climate are still unclear. Here, we show that the glacial Zackenberg river (Northeastern Greenland) exports aged particulate OC (POC, uncalibrated radiocarbon ages of \uffe2\uff88\uffbc4,000\uffc2\uffa0years). Many of the smaller periglacial streams affected by abrupt permafrost thaw transport substantially older POC (up to 32,000\uffc2\uffa0years), especially with enhanced discharge following intense precipitation. Mineralogical analysis, and density and size fractionation of soils and both glacial and nonglacial river sediments reveal that OC is largely associated with phyllosilicate minerals, suggesting stabilization against microbial processing. Enhanced export of ancient, mineral\uffe2\uff80\uff90associated OC as a consequence of summer rainfall may accelerate translocation of OC from terrestrial to marine environments, but could have limited consequences for climate.The Arctic is warming and significant changes to the landscape, including increased vegetative cover (\uffe2\uff80\uff9cgreening\uffe2\uff80\uff9d), are expected in the near future. These landscape changes may alter nitrogen (N) availability in terrestrial, stream, and coastal ecosystems, where production is often N limited, but the exact changes in nutrient cycling are uncertain. Here, we analyzed the relationship between vegetation greenness (i.e., NDVI) and dissolved inorganic (DIN) and organic (DON) concentrations in streams draining 14 headwater catchments (mean 3.6\uffc2\uffa0km2, range 0.4\uffe2\uff80\uff9311\uffc2\uffa0km2) across three samplings in the Zackenberg area, Northeast Greenland. We found large variation in DIN and DON concentrations across the sampled streams. We further show that this variation is correlated to water temperature and catchment NDVI, such that increased vegetation greenness and temperature correlated with lower DIN, and increased greenness also correlated with higher DON concentrations in streams. The results suggest that increased terrestrial vegetation due to rising air temperature could substantially alter dissolved N concentrations and form in streams, with potentially cascading impacts on coastal areas.The Arctic is warming and significant changes to the landscape, including increased vegetative cover (\uffe2\uff80\uff9cgreening\uffe2\uff80\uff9d), are expected in the near future. These landscape changes may alter nitrogen (N) availability in terrestrial, stream, and coastal ecosystems, where production is often N limited, but the exact changes in nutrient cycling are uncertain. Here, we analyzed the relationship between vegetation greenness (i.e., NDVI) and dissolved inorganic (DIN) and organic (DON) concentrations in streams draining 14 headwater catchments (mean 3.6\uffc2\uffa0km2, range 0.4\uffe2\uff80\uff9311\uffc2\uffa0km2) across three samplings in the Zackenberg area, Northeast Greenland. We found large variation in DIN and DON concentrations across the sampled streams. We further show that this variation is correlated to water temperature and catchment NDVI, such that increased vegetation greenness and temperature correlated with lower DIN, and increased greenness also correlated with higher DON concentrations in streams. The results suggest that increased terrestrial vegetation due to rising air temperature could substantially alter dissolved N concentrations and form in streams, with potentially cascading impacts on coastal areas.Recent hypotheses, based on atmospheric records and models, suggest that permafrost carbon (PF-C) accumulated during the last glaciation may have been an important source for the atmospheric CO2 rise during post-glacial warming. However, direct physical indications for such PF-C release have so far been absent. Here we use the Laptev Sea (Arctic Ocean) as an archive to investigate PF-C destabilization during the last glacial\uffe2\uff80\uff93interglacial period. Our results show evidence for massive supply of PF-C from Siberian soils as a result of severe active layer deepening in response to the warming. Thawing of PF-C must also have brought about an enhanced organic matter respiration and, thus, these findings suggest that PF-C may indeed have been an important source of CO2 across the extensive permafrost domain. The results challenge current paradigms on the post-glacial CO2 rise and, at the same time, serve as a harbinger for possible consequences of the present-day warming of PF-C soils.Rapid temperature and precipitation changes in High Arctic tundra ecosystems are altering the biogeochemical cycles of carbon (C) and nitrogen (N), but in ways that are difficult to predict. The challenge grows from the uncertainty of N cycle responses and the extent to which shifts in soil N are coupled with the C cycle and productivity of tundra systems. We used a long\uffe2\uff80\uff90term (since 2003) experiment of summer warming and supplemental summer water additions to a High Arctic ecosystem in NW Greenland, and applied a combination of discrete sampling and in situ soil core incubations to measure C and N pools and seasonal microbial processes that might control plant\uffe2\uff80\uff90available N. We hypothesized that elevated temperature and increased precipitation would stimulate microbial activity and net inorganic N mineralization, thereby increasing plant N\uffe2\uff80\uff90availability through the growing season. While we did find increased N mineralization rates under both global change scenarios, water addition also significantly increased net nitrification rates, loss of NO3\uffe2\uff88\uff92\uffe2\uff80\uff90N via leaching, and lowered rates of labile organic N production. We also expected the chronic warming and watering would lead to long\uffe2\uff80\uff90term changes in soil N\uffe2\uff80\uff90cycling that would be reflected in soil \uffce\uffb415N values. We found that soil \uffce\uffb415N decreased under the different climate change scenarios. Our results suggest that temperature accelerates biological processes and existing C and N transformations, but moisture increases soil hydraulic connectivity and so alters the pathways, and changes the fate of the products of C and N transformations. In addition, our findings indicate that warmer, wetter High Arctic tundra will be cycling N and C in ways that may transform these landscapes in part leading to greater C sequestration, but simultaneously, N losses from the upper soil profile that may be transported to depth dissolved in water and or transported off site in lateral flow.
", "keywords": ["Arctic Regions", "Nitrogen", "Rain", "Greenland", "Temperature", "Water", "Salix", "04 agricultural and veterinary sciences", "15. Life on land", "01 natural sciences", "Carbon", "Plant Leaves", "Soil", "13. Climate action", "0401 agriculture", " forestry", " and fisheries", "Fluorides", " Topical", "Rosaceae", "Soil Microbiology", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1111/gcb.12318"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Global%20Change%20Biology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/gcb.12318", "name": "item", "description": "10.1111/gcb.12318", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/gcb.12318"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2013-09-11T00:00:00Z"}}, {"id": "10.5061/dryad.mf3gd/9", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-19T16:19:10Z", "type": "Dataset", "title": "real-model1", "description": "settings and output for migrate-N model 1", "keywords": ["Spitsbergen", "Sweden", "Speciation", "the Netherlands", "Greenland", "population genetics", "SNP", "admixture", "Branta leucopsis", "cultural evolution", "migration modelling", "Russia"], "contacts": [{"organization": "Jonker, Rudy M., Kraus, Robert H. S., Zhang, Qiong, Van Hooft, Pim, Larsson, Kjell, Van Der Jeugd, Henk P., Kurvers, Ralf H. J. M., Van Wieren, Sip E., Loonen, Maarten J. J. E., Crooijmans, Richard P. M. A., Ydenberg, Ronald C., Groenen, Martien A. M., Prins, Herbert H. T.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.5061/dryad.mf3gd/9"}, {"rel": "self", "type": "application/geo+json", "title": "10.5061/dryad.mf3gd/9", "name": "item", "description": "10.5061/dryad.mf3gd/9", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.5061/dryad.mf3gd/9"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2013-01-01T00:00:00Z"}}, {"id": "20.500.11850/582974", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-19T16:21:40Z", "type": "Journal Article", "created": "2022-11-01", "title": "Contrasting Export of Particulate Organic Carbon From Greenlandic Glacial and Nonglacial Streams", "description": "AbstractOn\uffe2\uff80\uff90going shrinkage of Greenland's icecap, permafrost thaw, and changes in precipitation are exposing its landscapes to erosion and remobilization of ancient organic carbon (OC) held in soils and sedimentary rocks. The fate of this OC and potential feedbacks to climate are still unclear. Here, we show that the glacial Zackenberg river (Northeastern Greenland) exports aged particulate OC (POC, uncalibrated radiocarbon ages of \uffe2\uff88\uffbc4,000\uffc2\uffa0years). Many of the smaller periglacial streams affected by abrupt permafrost thaw transport substantially older POC (up to 32,000\uffc2\uffa0years), especially with enhanced discharge following intense precipitation. Mineralogical analysis, and density and size fractionation of soils and both glacial and nonglacial river sediments reveal that OC is largely associated with phyllosilicate minerals, suggesting stabilization against microbial processing. Enhanced export of ancient, mineral\uffe2\uff80\uff90associated OC as a consequence of summer rainfall may accelerate translocation of OC from terrestrial to marine environments, but could have limited consequences for climate.Recent hypotheses, based on atmospheric records and models, suggest that permafrost carbon (PF-C) accumulated during the last glaciation may have been an important source for the atmospheric CO2 rise during post-glacial warming. However, direct physical indications for such PF-C release have so far been absent. Here we use the Laptev Sea (Arctic Ocean) as an archive to investigate PF-C destabilization during the last glacial\uffe2\uff80\uff93interglacial period. Our results show evidence for massive supply of PF-C from Siberian soils as a result of severe active layer deepening in response to the warming. Thawing of PF-C must also have brought about an enhanced organic matter respiration and, thus, these findings suggest that PF-C may indeed have been an important source of CO2 across the extensive permafrost domain. The results challenge current paradigms on the post-glacial CO2 rise and, at the same time, serve as a harbinger for possible consequences of the present-day warming of PF-C soils.