The ice-free McMurdo Dry Valleys of Antarctica are dominated by nutrient-poor mineral soil and rocky outcrops. The principal habitat for microorganisms is within rocks (endolithic). In this environment, microorganisms are provided with protection against sub-zero temperatures, rapid thermal fluctuations, extreme dryness, and ultraviolet and solar radiation. Endolithic communities include lichen, algae, fungi, and a diverse array of bacteria. Chloroflexota is among the most abundant bacterial phyla present in these communities. Among the Chloroflexota are four novel classes of bacteria, here named Candidatus Spiritibacteria class. nov. (=UBA5177), Candidatus Martimicrobia class. nov. (=UBA4733), Candidatus Tarhunnaeia class. nov. (=UBA6077), and Candidatus Uliximicrobia class. nov. (=UBA2235). We retrieved 17 high-quality metagenome-assembled genomes (MAGs) that represent these four classes. Based on genome predictions, all these bacteria are inferred to be aerobic heterotrophs that encode enzymes for the catabolism of diverse sugars. These and other organic substrates are likely derived from lichen, algae, and fungi, as metabolites (including photosynthate), cell wall components, and extracellular matrix components. The majority of MAGs encode the capacity for trace gas oxidation using high-affinity uptake hydrogenases, which could provide energy and metabolic water required for survival and persistence. Furthermore, some MAGs encode the capacity to couple the energy generated from H 2 and CO oxidation to support carbon fixation (atmospheric chemosynthesis). All encode mechanisms for the detoxification and efflux of heavy metals. Certain MAGs encode features that indicate possible interactions with other organisms, such as Tc-type toxin complexes, hemolysins, and macroglobulins.
IMPORTANCEThe ice-free McMurdo Dry Valleys of Antarctica are the coldest and most hyperarid desert on Earth. It is, therefore, the closest analog to the surface of the planet Mars. Bacteria and other microorganisms survive by inhabiting airspaces within rocks (endolithic). We identify four novel classes of phylum Chloroflexota , and, based on interrogation of 17 metagenome-assembled genomes, we predict specific metabolic and physiological adaptations that facilitate the survival of these bacteria in this harsh environment\uffe2\uff80\uff94including oxidation of trace gases and the utilization of nutrients (including sugars) derived from lichen, algae, and fungi. We propose that such adaptations allow these endolithic bacteria to eke out an existence in this cold and extremely dry habitat.
", "keywords": ["570", "Bacteria", "Fungi", "Antarctic Regions", "Chloroflexi", "15. Life on land", "Survival strategies", "Cold Temperature", "Extremophiles", "13. Climate action", "Antarctica", "Endolithic communities", "Metagenomics", "14. Life underwater", "Sugars", "Settore BIO/19 - MICROBIOLOGIA GENERALE"]}, "links": [{"href": "https://doi.org/10.1128/aem.02264-23"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Applied%20and%20Environmental%20Microbiology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1128/aem.02264-23", "name": "item", "description": "10.1128/aem.02264-23", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1128/aem.02264-23"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2024-02-19T00:00:00Z"}}, {"id": "10.1111/gcb.14582", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:17:48Z", "type": "Journal Article", "created": "2019-02-26", "title": "Volatile emissions from thawing permafrost soils are influenced by meltwater drainage conditions", "description": "AbstractVast amounts of carbon are bound in both active layer and permafrost soils in the Arctic. As a consequence of climate warming, the depth of the active layer is increasing in size and permafrost soils are thawing. We hypothesize that pulses of biogenic volatile organic compounds are released from the near\uffe2\uff80\uff90surface active layer during spring, and during late summer season from thawing permafrost, while the subsequent biogeochemical processes occurring in thawed soils also lead to emissions. Biogenic volatile organic compounds are reactive gases that have both negative and positive climate forcing impacts when introduced to the Arctic atmosphere, and the knowledge of their emission magnitude and pattern is necessary to construct reliable climate models. However, it is unclear how different ecosystems and environmental factors such as drainage conditions upon permafrost thaw affect the emission and compound composition. Here we show that incubations of frozen B horizon of the active layer and permafrost soils collected from a High Arctic heath and fen release a range of biogenic volatile organic compounds upon thaw and during subsequent incubation experiments at temperatures of 10\uffc2\uffb0C and 20\uffc2\uffb0C. Meltwater drainage in the fen soils increased emission rates nine times, while having no effect in the drier heath soils. Emissions generally increased with temperature, and emission profiles for the fen soils were dominated by benzenoids and alkanes, while benzenoids, ketones, and alcohols dominated in heath soils. Our results emphasize that future changes affecting the drainage conditions of the Arctic tundra will have a large influence on volatile emissions from thawing permafrost soils \uffe2\uff80\uff93 particularly in wetland/fen areas.
", "keywords": ["0301 basic medicine", "tundra", "Climate Change", "Permafrost", "01 natural sciences", "meltwater drainage", "Soil", "03 medical and health sciences", "Arctic", "11. Sustainability", "biogenic volatile organic compounds", "gas fluxes", "Tundra", "0105 earth and related environmental sciences", "Volatile Organic Compounds", "Arctic Regions", "Water", "15. Life on land", "soil ecology", "climate change", "13. Climate action", "Gases", "Seasons", "permafrost", "Environmental Monitoring"]}, "links": [{"href": "https://onlinelibrary.wiley.com/doi/pdf/10.1111/gcb.14582"}, {"href": "https://doi.org/10.1111/gcb.14582"}, {"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.14582", "name": "item", "description": "10.1111/gcb.14582", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/gcb.14582"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-02-25T00:00:00Z"}}, {"id": "10.1002/2017gb005693", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:14:24Z", "type": "Journal Article", "created": "2017-10-02", "title": "Release of Black Carbon From Thawing Permafrost Estimated by Sequestration Fluxes in the East Siberian Arctic Shelf Recipient", "description": "AbstractBlack carbon (BC) plays an important role in carbon burial in marine sediments globally. Yet the sequestration of BC in the Arctic Ocean is poorly understood. Here we assess the concentrations, fluxes, and sources of soot BC (SBC)\uffe2\uff80\uff94the most refractory component of BC\uffe2\uff80\uff94in sediments from the East Siberian Arctic Shelf (ESAS), the World's largest shelf sea system. SBC concentrations in the contemporary shelf sediments range from 0.1 to 2.1\uffc2\uffa0mg\uffc2\uffa0g\uffe2\uff88\uff921\uffc2\uffa0dw, corresponding to 2\uffe2\uff80\uff9312% of total organic carbon. The 210Pb\uffe2\uff80\uff90derived fluxes of SBC (0.42\uffe2\uff80\uff9311\uffc2\uffa0g\uffc2\uffa0m\uffe2\uff88\uff922\uffc2\uffa0yr\uffe2\uff88\uff921) are higher or in the same range as fluxes reported for marine surface sediments closer to anthropogenic emissions. The total burial flux of SBC in the ESAS (~4,000\uffc2\uffa0Gg\uffc2\uffa0yr\uffe2\uff88\uff921) illustrates the great importance of this Arctic shelf in marine sequestration of SBC. The radiocarbon signal of the SBC shows more depleted yet also more uniform signatures (\uffe2\uff88\uff92721 to \uffe2\uff88\uff92896\uffe2\uff80\uffb0; average of \uffe2\uff88\uff92774\uffc2\uffa0\uffc2\uffb1\uffc2\uffa062\uffe2\uff80\uffb0) than of the non\uffe2\uff80\uff90SBC pool (\uffe2\uff88\uff92304 to \uffe2\uff88\uff92728\uffe2\uff80\uffb0; average of \uffe2\uff88\uff92491\uffc2\uffa0\uffc2\uffb1\uffc2\uffa0163\uffe2\uff80\uffb0), suggesting that SBC is coming from an, on average, 5,900\uffc2\uffa0\uffc2\uffb1\uffc2\uffa0300\uffc2\uffa0years older and more specific source than the non\uffe2\uff80\uff90SBC pool. We estimate that the atmospheric BC input to the ESAS is negligible (~0.6% of the SBC burial flux). Statistical source apportionment modeling suggests that the ESAS sedimentary SBC is remobilized by thawing of two permafrost carbon (PF/C) systems: surface soil permafrost (topsoil/PF; 25\uffc2\uffa0\uffc2\uffb1\uffc2\uffa08%) and Pleistocene ice complex deposits (ICD/PF; 75\uffc2\uffa0\uffc2\uffb1\uffc2\uffa08%). The SBC contribution to the total mobilized permafrost carbon (PF/C) increases with increasing distance from the coast (from 5 to 14%), indicating that the SBC is more recalcitrant than other forms of translocated PF/C. These results elucidate for the first time the key role of permafrost thaw in the transport of SBC to the Arctic Ocean. With ongoing global warming, these findings have implications for the biogeochemical carbon cycle, increasing the size of this refractory carbon pool in the Arctic Ocean.Herbivores can exert major controls over biogeochemical cycling. As invertebrates are highly sensitive to temperature shifts (ectothermal), the abundances of insects in high\uffe2\uff80\uff90latitude systems, where climate warming is rapid, is expected to increase. In subarctic mountain birch forests, research has focussed on geometrid moth outbreaks, while the contribution of background insect herbivory (BIH) to elemental cycling is poorly constrained. In northern Sweden, we estimated BIH along 9 elevational gradients distributed across a gradient in regional elevation, temperature, and precipitation to allow evaluation of consistency in local versus regional variation. We converted foliar loss via BIH to fluxes of C, nitrogen (N), and phosphorus (P) from the birch canopy to the soil to compare with other relevant soil inputs of the same elements and assessed different abiotic and biotic drivers of the observed variability. We found that leaf area loss due to BIH was ~1.6% on average. This is comparable to estimates from tundra, but considerably lower than ecosystems at lower latitudes. The C, N, and P fluxes from canopy to soil associated with BIH were 1\uffe2\uff80\uff932 orders of magnitude lower than the soil input from senesced litter and external nutrient sources such as biological N fixation, atmospheric deposition of N, and P weathering estimated from the literature. Despite the minor contribution to overall elemental cycling in subarctic birch forests, the higher quality and earlier timing of the input of herbivore deposits to soils compared to senesced litter may make this contribution disproportionally important for various ecosystem functions. BIH increased significantly with leaf N content as well as local elevation along each transect, yet showed no significant relationship with temperature or humidity, nor the commonly used temperature proxy, absolute elevation. The lack of consistency between the local and regional elevational trends calls for caution when using elevation gradients as climate proxies.Black carbon (BC) plays an important role in carbon burial in marine sediments globally. Yet the sequestration of BC in the Arctic Ocean is poorly understood. Here we assess the concentrations, fluxes, and sources of soot BC (SBC)\uffe2\uff80\uff94the most refractory component of BC\uffe2\uff80\uff94in sediments from the East Siberian Arctic Shelf (ESAS), the World's largest shelf sea system. SBC concentrations in the contemporary shelf sediments range from 0.1 to 2.1\uffc2\uffa0mg\uffc2\uffa0g\uffe2\uff88\uff921\uffc2\uffa0dw, corresponding to 2\uffe2\uff80\uff9312% of total organic carbon. The 210Pb\uffe2\uff80\uff90derived fluxes of SBC (0.42\uffe2\uff80\uff9311\uffc2\uffa0g\uffc2\uffa0m\uffe2\uff88\uff922\uffc2\uffa0yr\uffe2\uff88\uff921) are higher or in the same range as fluxes reported for marine surface sediments closer to anthropogenic emissions. The total burial flux of SBC in the ESAS (~4,000\uffc2\uffa0Gg\uffc2\uffa0yr\uffe2\uff88\uff921) illustrates the great importance of this Arctic shelf in marine sequestration of SBC. The radiocarbon signal of the SBC shows more depleted yet also more uniform signatures (\uffe2\uff88\uff92721 to \uffe2\uff88\uff92896\uffe2\uff80\uffb0; average of \uffe2\uff88\uff92774\uffc2\uffa0\uffc2\uffb1\uffc2\uffa062\uffe2\uff80\uffb0) than of the non\uffe2\uff80\uff90SBC pool (\uffe2\uff88\uff92304 to \uffe2\uff88\uff92728\uffe2\uff80\uffb0; average of \uffe2\uff88\uff92491\uffc2\uffa0\uffc2\uffb1\uffc2\uffa0163\uffe2\uff80\uffb0), suggesting that SBC is coming from an, on average, 5,900\uffc2\uffa0\uffc2\uffb1\uffc2\uffa0300\uffc2\uffa0years older and more specific source than the non\uffe2\uff80\uff90SBC pool. We estimate that the atmospheric BC input to the ESAS is negligible (~0.6% of the SBC burial flux). Statistical source apportionment modeling suggests that the ESAS sedimentary SBC is remobilized by thawing of two permafrost carbon (PF/C) systems: surface soil permafrost (topsoil/PF; 25\uffc2\uffa0\uffc2\uffb1\uffc2\uffa08%) and Pleistocene ice complex deposits (ICD/PF; 75\uffc2\uffa0\uffc2\uffb1\uffc2\uffa08%). The SBC contribution to the total mobilized permafrost carbon (PF/C) increases with increasing distance from the coast (from 5 to 14%), indicating that the SBC is more recalcitrant than other forms of translocated PF/C. These results elucidate for the first time the key role of permafrost thaw in the transport of SBC to the Arctic Ocean. With ongoing global warming, these findings have implications for the biogeochemical carbon cycle, increasing the size of this refractory carbon pool in the Arctic Ocean.
", "keywords": ["13. Climate action", "Arctic Ocean", "SDG 14 - Life Below Water", "14. Life underwater", "black carbon", "01 natural sciences", "permafrost", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2017GB005693"}, {"href": "https://doi.org/10.1002/2017GB005693"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Global%20Biogeochemical%20Cycles", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1002/2017GB005693", "name": "item", "description": "10.1002/2017GB005693", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1002/2017GB005693"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2017-10-01T00:00:00Z"}}, {"id": "10.1002/2017jg004139", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:14:24Z", "type": "Journal Article", "created": "2017-12-12", "title": "Acclimation of Biogenic Volatile Organic Compound Emission From Subarctic Heath Under Long-Term Moderate Warming", "description": "AbstractBiogenic volatile organic compound (BVOC) emissions from subarctic ecosystems have shown to increase drastically in response to a long\uffe2\uff80\uff90term temperature increase of only 2\uffc2\uffb0C. We assessed whether this increase takes place already after 3\uffc2\uffa0years of warming and how the increase changes over time. To test this, we measured BVOC emissions and CO2 fluxes in a field experiment on a subarctic wet heath, where ecosystem plots were subjected to passive warming by open top chambers for 3 (OTC3) or 13\uffc2\uffa0years (OTC13) or were kept as unmanipulated controls. Already after 3\uffc2\uffa0years of moderate temperature increase of 1\uffe2\uff80\uff932\uffc2\uffb0C, warming increased the emissions of isoprene (five\uffe2\uff80\uff90 to sixfold) and monoterpenes (three\uffe2\uff80\uff90 to fourfold) from the subarctic heath. The several\uffe2\uff80\uff90fold higher BVOC emissions in the warmed plots are likely a result of increased vegetation biomass and altered vegetation composition as a shift in the species coverage was observed already after 3\uffc2\uffa0years of warming. Warming also increased gross ecosystem production and ecosystem respiration, but the increases were much lower than those for BVOCs. Our results demonstrate that the strong BVOC responses to warming already appeared after 3\uffc2\uffa0years, and the BVOC and CO2 fluxes had acclimated to this warming after 3\uffc2\uffa0years, showing no differences with another 10\uffc2\uffa0years of warming. This finding has important implications for predicting CO2 and BVOC fluxes in subarctic ecosystems.
", "keywords": ["BVOC", "Arctic", "climate change", "tundra", "13. Climate action", "CO2 exchange", "11. Sustainability", "15. Life on land", "isoprene", "01 natural sciences", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2017JG004139"}, {"href": "https://doi.org/10.1002/2017jg004139"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Journal%20of%20Geophysical%20Research%3A%20Biogeosciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1002/2017jg004139", "name": "item", "description": "10.1002/2017jg004139", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1002/2017jg004139"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-01-01T00:00:00Z"}}, {"id": "10.1002/ecy.2137", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:14:26Z", "type": "Journal Article", "created": "2018-01-10", "title": "Ecological drivers of soil microbial diversity and soil biological networks in the Southern Hemisphere", "description": "AbstractThe ecological drivers of soil biodiversity in the Southern Hemisphere remain underexplored. Here, in a continental survey comprising 647 sites, across 58 degrees of latitude between tropical Australia and Antarctica, we evaluated the major ecological patterns in soil biodiversity and relative abundance of ecological clusters within a co\uffe2\uff80\uff90occurrence network of soil bacteria, archaea and eukaryotes. Six major ecological clusters (modules) of co\uffe2\uff80\uff90occurring soil taxa were identified. These clusters exhibited strong shifts in their relative abundances with increasing distance from the equator. Temperature was the major environmental driver of the relative abundance of ecological clusters when Australia and Antarctica are analyzed together. Temperature, aridity, soil properties and vegetation types were the major drivers of the relative abundance of different ecological clusters within Australia. Our data supports significant reductions in the diversity of bacteria, archaea and eukaryotes in Antarctica vs. Australia linked to strong reductions in temperature. However, we only detected small latitudinal variations in soil biodiversity within Australia. Different environmental drivers regulate the diversity of soil archaea (temperature and soil carbon), bacteria (aridity, vegetation attributes and pH) and eukaryotes (vegetation type and soil carbon) across Australia. Together, our findings provide new insights into the mechanisms driving soil biodiversity in the Southern Hemisphere.Meiofauna (all invertebrates smaller than 1\uffe2\uff80\uff89mm) are not only sensitive to environmental changes but also contribute significantly to nutrient cycling and energy transfer to higher trophic levels. Despite their importance, meiofauna distribution and ecology in the Siberian seas remain understudied. Here, we employ sediment environmental DNA metabarcoding to characterize meiofauna diversity across the unexplored Siberian seas. We show that meiofauna community structure is primarily driven by river discharge and coastal erosion, which are heavily influenced by climate change, rather than geographical distinctions between the seas. We observed higher meiofauna diversity in nearshore areas where river plumes promoted colonizer nematode communities that are resilient to disturbances. Yet, their dominance may lead to decreased ecosystem stability in the future. This study provides a valuable baseline for meiofauna diversity in remote Siberian seas undergoing rapid environmental change, which will be useful for assessing the future direction and pace of benthic ecological trajectories.The stabilizing properties of mineral\uffe2\uff80\uff93organic carbon (OC) interactions have been studied in many soil environments (temperate soils, podzol lateritic soils, and paddy soils). Recently, interest in their role in permafrost regions is increasing as permafrost was identified as a hotspot of change. In thawing ice\uffe2\uff80\uff90rich permafrost regions, such as the Yedoma domain, 327\uffe2\uff80\uff93466 Gt of frozen OC is buried in deep sediments. Interactions between minerals and OC are important because OC is located very near the mineral matrix. Mineral surfaces and elements could mitigate recent and future greenhouse gas emissions through physical and/or physicochemical protection of OC. The dynamic changes in redox and pH conditions associated with thermokarst lake formation and drainage trigger metal\uffe2\uff80\uff90oxide dissolution and precipitation, likely influencing OC stabilization and microbial mineralization. However, the influence of thermokarst processes on mineral\uffe2\uff80\uff93OC interactions remains poorly constrained. In this study, we aim to characterize Fe, Mn, Al, and Ca minerals and their potential protective role for OC. Total and selective extractions were used to assess the crystalline and amorphous oxides or complexed metal pools as well as the organic acids found within these pools. We analyzed four sediment cores from an ice\uffe2\uff80\uff90rich permafrost area in Central Yakutia, which were drilled (i) in undisturbed Yedoma uplands, (ii) beneath a recent lake formed within Yedoma deposits, (iii) in a drained thermokarst lake basin, and (iv) beneath a mature thermokarst lake from the early Holocene period. We find a decrease in the amount of reactive Fe, Mn, Al, and Ca in the deposits on lake formation (promoting reduction reactions), and this was largely balanced by an increase in the amount of reactive metals in the deposits on lake drainage (promoting oxidation reactions). We demonstrate an increase in the metal to C molar ratio on thermokarst process, which may indicate an increase in metal\uffe2\uff80\uff93C bindings and could provide a higher protective role against microbial mineralization of organic matter. Finally, we find that an increase in mineral\uffe2\uff80\uff93OC interactions corresponded to a decrease in CO2 and CH4 gas emissions on thermokarst process. Mineral\uffe2\uff80\uff93OC interactions could mitigate greenhouse gas production from permafrost thaw as soon as lake drainage occurs.
", "keywords": ["Yedoma", "ddc:550", "04 agricultural and veterinary sciences", "15. Life on land", "01 natural sciences", "redox processes", "Arctic", "organic carbon stabilization", "13. Climate action", "0401 agriculture", " forestry", " and fisheries", "Institut f\u00fcr Geowissenschaften", "thaw", "permafrost", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://onlinelibrary.wiley.com/doi/pdf/10.1002/ppp.2162"}, {"href": "https://doi.org/10.1002/ppp.2162"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Permafrost%20and%20Periglacial%20Processes", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1002/ppp.2162", "name": "item", "description": "10.1002/ppp.2162", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1002/ppp.2162"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-07-24T00:00:00Z"}}, {"id": "10.1007%2fbf00328785", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:14:32Z", "type": "Journal Article", "created": "2004-10-21", "title": "Shoot Biomass, ?13c, Nitrogen And Chlorophyll Responses Of Two Arctic Dwarf Shrubs To In Situ Shading, Nutrient Application And Warming Simulating Climatic Change", "description": "As climatic change might induce ecophysiological changes in plants which affect their long-term performance, we investigated responses in above-ground biomass, \u03b413C, nitrogen and chlorophyll of two evergreen arctic dwarf shrubs, Cassiope tetragona and Empetrum hermaphroditum, to 5 (biomass, N) or 6 years of shading, nutrient application and air/soil warming at a dwarf shrub dominated tree-line heath (450 m a.s.l) and a high altitude fellfield (1100 m a.s.l.) in Swedish Lapland. Warming enhanced the green biomass (equivalent to the last 3-4 years of leaf production) and the ratio of green to brown biomass of C. tetragona at the fellfield, and diluted the shoot N concentration. Fertilizer application led to higher shoot N concentration and larger green-to-brown biomass ratio at both sites, and fertilizer application and warming generally had an additive effect on the green biomass. We conclude that both warming and increased soil nutrient availability stimulated the growth of C. tetragona at the fellfield whereas at the heath there was a clear increase in production only if enhanced temperature was combined with nutrient application. Across treatments C. tetragona at the fellfield had 0.6\u2030 higher \u03b413C and 1.4 mg g-1 more leaf N, and the soil organic matter \u03b413C was 1.0\u2030 higher at the fellfield than at the heath. However, an increase in shoot N concentration with altitude does not necessarily lead to higher \u03b413C as no differences in \u03b413C were observed when leaf N of the two dwarf shrubs was increased by fertilizer application c. tetragona in non-warmed plots had higher \u03b413C values than those from warmed plots at the same altitude, which provides the first in situ experimental validation of the theory that temperature partly is responsible for altitudinal trends in plant carbon isotope discrimination. Increased biomass and chlorophyll concentration of C. tetragona in warmed plots points to increased assimilation, at least at the fellfield. As the \u03b413C-based and, therefore, time-integrated estimate of the ratio of CO2 concentration in the leaf intercellular spaces to that in the atmosphere (C i/C a) also increased, warming probably enhanced the stomatal conductance relatively more than the C assimilation, which may be harmful if climatic change leads to reduced soil moisture content and increased plant competition for water. At both sites C. tetragona and E. hermaphroditum responded to shade by increasing the concentration of shoot N and photosynthetic pigments whereas biomass production (and therefore also net photosynthesis) did not decline. Shade was accompanied by a 0.6-1.3\u2030 (E. hermaphroditum) or 1.2-2.2\u2030 (C. tetragona) decrease in \u03b413C. This could be due to enhanced stomatal conductance with shading, and perhaps to shade reducing the ericoid mycorrhizal uptake of soil organic C, a factor which has been overlooked as an influence on plant \u03b413C.", "keywords": ["0106 biological sciences", "jord", "plants", "04 agricultural and veterinary sciences", "15. Life on land", "planter", "01 natural sciences", "soil", "climate change", "mikroorganismer", "13. Climate action", "Faculty of Science", "arctic", "0401 agriculture", " forestry", " and fisheries", "\u00f8kologi", "/dk/atira/pure/core/keywords/TheFacultyOfScience", "arktis", "ecology", "microorganisms"]}, "links": [{"href": "https://doi.org/10.1007%2fbf00328785"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Oecologia", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1007%2fbf00328785", "name": "item", "description": "10.1007%2fbf00328785", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007%2fbf00328785"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "1996-01-01T00:00:00Z"}}, {"id": "10.1007/bf00328785", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:14:36Z", "type": "Journal Article", "created": "2004-10-21", "title": "Shoot Biomass, Delta C-13, Nitrogen And Chlorophyll Responses Of Two Arctic Dwarf Shrubs To In Situ Shading, Nutrient Application And Warming Simulating Climatic Change", "description": "As climatic change might induce ecophysiological changes in plants which affect their long-term performance, we investigated responses in above-ground biomass, \u03b413C, nitrogen and chlorophyll of two evergreen arctic dwarf shrubs, Cassiope tetragona and Empetrum hermaphroditum, to 5 (biomass, N) or 6 years of shading, nutrient application and air/soil warming at a dwarf shrub dominated tree-line heath (450 m a.s.l) and a high altitude fellfield (1100 m a.s.l.) in Swedish Lapland. Warming enhanced the green biomass (equivalent to the last 3-4 years of leaf production) and the ratio of green to brown biomass of C. tetragona at the fellfield, and diluted the shoot N concentration. Fertilizer application led to higher shoot N concentration and larger green-to-brown biomass ratio at both sites, and fertilizer application and warming generally had an additive effect on the green biomass. We conclude that both warming and increased soil nutrient availability stimulated the growth of C. tetragona at the fellfield whereas at the heath there was a clear increase in production only if enhanced temperature was combined with nutrient application. Across treatments C. tetragona at the fellfield had 0.6\u2030 higher \u03b413C and 1.4 mg g-1 more leaf N, and the soil organic matter \u03b413C was 1.0\u2030 higher at the fellfield than at the heath. However, an increase in shoot N concentration with altitude does not necessarily lead to higher \u03b413C as no differences in \u03b413C were observed when leaf N of the two dwarf shrubs was increased by fertilizer application c. tetragona in non-warmed plots had higher \u03b413C values than those from warmed plots at the same altitude, which provides the first in situ experimental validation of the theory that temperature partly is responsible for altitudinal trends in plant carbon isotope discrimination. Increased biomass and chlorophyll concentration of C. tetragona in warmed plots points to increased assimilation, at least at the fellfield. As the \u03b413C-based and, therefore, time-integrated estimate of the ratio of CO2 concentration in the leaf intercellular spaces to that in the atmosphere (C i/C a) also increased, warming probably enhanced the stomatal conductance relatively more than the C assimilation, which may be harmful if climatic change leads to reduced soil moisture content and increased plant competition for water. At both sites C. tetragona and E. hermaphroditum responded to shade by increasing the concentration of shoot N and photosynthetic pigments whereas biomass production (and therefore also net photosynthesis) did not decline. Shade was accompanied by a 0.6-1.3\u2030 (E. hermaphroditum) or 1.2-2.2\u2030 (C. tetragona) decrease in \u03b413C. This could be due to enhanced stomatal conductance with shading, and perhaps to shade reducing the ericoid mycorrhizal uptake of soil organic C, a factor which has been overlooked as an influence on plant \u03b413C.", "keywords": ["0106 biological sciences", "jord", "plants", "04 agricultural and veterinary sciences", "15. Life on land", "planter", "01 natural sciences", "soil", "climate change", "mikroorganismer", "13. Climate action", "Faculty of Science", "arctic", "0401 agriculture", " forestry", " and fisheries", "\u00f8kologi", "/dk/atira/pure/core/keywords/TheFacultyOfScience", "arktis", "ecology", "microorganisms"]}, "links": [{"href": "https://doi.org/10.1007/bf00328785"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Oecologia", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1007/bf00328785", "name": "item", "description": "10.1007/bf00328785", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/bf00328785"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "1996-01-01T00:00:00Z"}}, {"id": "10.1016/j.geoderma.2022.115915", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:16:05Z", "type": "Journal Article", "created": "2022-05-02", "title": "Mineral element recycling in topsoil following permafrost degradation and a vegetation shift in sub-Arctic tundra", "description": "Climate change affects the Arctic and sub-Arctic regions by exposing previously frozen permafrost to thaw, unlocking soil nutrients, changing hydrological processes, and boosting plant growth. As a result, sub-Arctic tundra is subject to a shrub expansion, called \u201cshrubification\u201d, at the expense of sedge species. Depending on the intrinsic foliar properties of these plant species, changes in foliar mineral element fluxes with shrubification in the context of permafrost degradation may influence topsoil mineral element composition. Despite the potential implications of changes in topsoil mineral element concentrations for the fate of organic carbon, this remains poorly quantified. Here, we investigate vegetation foliar and topsoil mineral element composition (Si, K, Ca, P, Mn, Zn, Cu, Mo, V) across a natural gradient of permafrost degradation at a typical sub-Arctic tundra at Eight Mile Lake (Alaska, USA). Results show that foliar mineral element concentrations are higher (up to 9 times; Si, K, Mo for all species, and for some species Zn) or lower (up to 2 times; Ca, P, Mn, Cu, V for all species, and for some species Zn) in sedge than in shrub species. As a result, a vegetation shift over ~40 years has resulted in lower topsoil concentrations in Si, K, Zn, and Mo (respectively of 52, 24, 20, and 51%) in highly degraded permafrost sites compared to poorly degraded permafrost sites due to lower foliar fluxes of these elements. For other elements (Ca, P, Mn, Cu, and V), the vegetation shift has not induced a marked change in topsoil concentrations at this current stage of permafrost degradation. A modeled amplified shrubification associated with a further permafrost degradation is expected to increase foliar Ca, P, Mn, Cu, and V fluxes, which will likely change these element concentrations in topsoil. These data can serve as a first estimate to assess the influence of other shifts in vegetation in Arctic and sub-Arctic tundra such as sedge expansion under wetter soil conditions.", "keywords": ["topsoil", "[SDV.SA.STA] Life Sciences [q-bio]/Agricultural sciences/Sciences and technics of agriculture", "mineral elements", "04 agricultural and veterinary sciences", "sub-Arctic tundra", "15. Life on land", "01 natural sciences", "vegetation change", "13. Climate action", "[SDV.SA.STA]Life Sciences [q-bio]/Agricultural sciences/Sciences and technics of agriculture", "0401 agriculture", " forestry", " and fisheries", "shrubification", "permafrost degradation", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1016/j.geoderma.2022.115915"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Geoderma", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.geoderma.2022.115915", "name": "item", "description": "10.1016/j.geoderma.2022.115915", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.geoderma.2022.115915"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-09-01T00:00:00Z"}}, {"id": "10.1007/s00114-021-01748-8", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-09-22T16:14:39Z", "type": "Journal Article", "created": "2021-09-07", "title": "Societal importance of Antarctic negative feedbacks on climate change: blue carbon gains from sea ice, ice shelf and glacier losses", "description": "AbstractDiminishing prospects for environmental preservation under climate change are intensifying efforts to boost capture, storage and sequestration (long-term burial) of carbon. However, as Earth\uffe2\uff80\uff99s biological carbon sinks also shrink, remediation has become a key part of the narrative for terrestrial ecosystems. In contrast, blue carbon on polar continental shelves have stronger pathways to sequestration and have increased with climate-forced marine ice losses\uffe2\uff80\uff94becoming the largest known natural negative feedback on climate change. Here we explore the size and complex dynamics of blue carbon gains with spatiotemporal changes in sea ice (60\uffe2\uff80\uff93100 MtCyear\uffe2\uff88\uff921), ice shelves (4\uffe2\uff80\uff9340 MtCyear\uffe2\uff88\uff921\uffe2\uff80\uff89=\uffe2\uff80\uff89giant iceberg generation) and glacier retreat (<\uffe2\uff80\uff891 MtCyear\uffe2\uff88\uff921). Estimates suggest that, amongst these, reduced duration of seasonal sea ice is most important. Decreasing sea ice extent drives longer (not necessarily larger biomass) smaller cell-sized phytoplankton blooms, increasing growth of many primary consumers and benthic carbon storage\uffe2\uff80\uff94where sequestration chances are maximal. However, sea ice losses also create positive feedbacks in shallow waters through increased iceberg movement and scouring of benthos. Unlike loss of sea ice, which enhances existing sinks, ice shelf losses generate brand new carbon sinks both where giant icebergs were, and in their wake. These also generate small positive feedbacks from scouring, minimised by repeat scouring at biodiversity hotspots. Blue carbon change from glacier retreat has been least well quantified, and although emerging fjords are small areas, they have high storage-sequestration conversion efficiencies, whilst blue carbon in polar waters faces many diverse and complex stressors. The identity of these are known (e.g. fishing, warming, ocean acidification, non-indigenous species and plastic pollution) but not their magnitude of impact. In order to mediate multiple stressors, research should focus on wider verification of blue carbon gains, projecting future change, and the broader environmental and economic benefits to safeguard blue carbon ecosystems through law.Background and aims: Permafrost degradation has the potential to change the Arctic tundra landscape. We observed rapid local thawing of ice-rich permafrost resulting in thaw pond formation, which was triggered by removal of the shrub cover in a field experiment. This study aimed to examine the rate of permafrost thaw and the initial vegetation succession after the permafrost collapse. Methods: In the experiment, we measured changes in soil thaw depth, plant species cover and soil subsidence over nine years (2007\u20132015). Results: After abrupt initial thaw, soil subsidence in the removal plots continued indicating further thawing of permafrost albeit at a much slower pace: 1 cm y\u22121 over 2012\u20132015 vs. 5 cm y\u22121 over 2007\u20132012. Grass cover strongly increased after the initial shrub removal, but later declined with ponding of water in the subsiding removal plots. Sedges established and expanded in the wetter removal plots. Thereby, the removal plots have become increasingly similar to nearby \u2018natural\u2019 thaw ponds. Conclusions: The nine years of field observations in a unique shrub removal experiment at a Siberian tundra site document possible trajectories of small-scale permafrost collapse and the initial stage of vegetation recovery, which is essential knowledge for assessing future tundra landscape changes.
", "keywords": ["0301 basic medicine", "Ecology (including Biodiversity Conservation)", "Permafrost degradation", "Betula nana", "15. Life on land", "01 natural sciences", "Thermokarst", "Vegetation dynamics", "03 medical and health sciences", "13. Climate action", "Arctic tundra", "Environmental Sciences", "SDG 15 - Life on Land", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1007/s11104-017-3369-8"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Plant%20and%20Soil", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1007/s11104-017-3369-8", "name": "item", "description": "10.1007/s11104-017-3369-8", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s11104-017-3369-8"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2017-08-22T00:00:00Z"}}, {"id": "10.1016/j.agsy.2022.103507", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:15:26Z", "type": "Journal Article", "created": "2022-09-22", "title": "The challenges fraught opportunity of agriculture expansion into boreal and Arctic regions", "description": "2022", "keywords": ["Land use and land use change", "Northern agriculture", "Arctic", "Climate change", "0401 agriculture", " forestry", " and fisheries", "04 agricultural and veterinary sciences", "Boreal", "01 natural sciences", "Perspectives", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1016/j.agsy.2022.103507"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Agricultural%20Systems", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.agsy.2022.103507", "name": "item", "description": "10.1016/j.agsy.2022.103507", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.agsy.2022.103507"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-12-01T00:00:00Z"}}, {"id": "10.1016/j.apsoil.2007.12.014", "type": "Feature", "geometry": null, "properties": {"license": "Closed Access", "updated": "2026-09-22T16:15:29Z", "type": "Journal Article", "created": "2008-03-06", "title": "Effects Of Litter Addition And Warming On Soil Carbon, Nutrient Pools And Microbial Communities In A Subarctic Heath Ecosystem", "description": "Climatic warming leads to the expansion of deciduous shrubs and trees in the Arctic. This leads to higher leaf litter inputs, which together with warming may alter the rate of carbon and nutrient cycling in the arctic ecosystems. We assessed effects of factorial warming and additional litter on the soil ecosystem of a subarctic heath in a 7-year-long field experiment. Fine root biomass, dissolved organic carbon (DOC) and total C concentration increased in response to warming, which probably was a result of the increased vegetation cover. Litter addition increased the concentration of inorganic P in the uppermost 5 cm soil, while decreasing the pool of total P per unit area of the organic profile and having no significant effects on N concentrations or pools. Microbial biomass C and N were unaffected by the treatments, while the microbial biomass P increased significantly with litter addition. Soil ergosterol concentration was also slightly increased by the added litter in the uppermost soil, although not statistically significantly. According to a principal component analysis of the phospholipid fatty acid profiles, litter addition differed from the other treatments by increasing the relative proportion of biomarkers for Gram-positive bacteria. The combined warming plus litter addition treatment decreased the soil water content in the uppermost 5 cm soil, which was a likely reason for many interactions between the effects of warming and litter addition. The soil organic matter quality of the combined treatment was also clearly different from the control based on a near-infrared reflectance (NIR) spectroscopic analysis, implying that the treatment altered the composition of soil organic matter. However, it appears that the biological processes and the microbial community composition responded more to the soil and litter moisture conditions than to the change in the quality of the organic matter.", "keywords": ["2. Zero hunger", "jord", "plants", "04 agricultural and veterinary sciences", "15. Life on land", "planter", "soil", "climate change", "13. Climate action", "Faculty of Science", "arctic", "0401 agriculture", " forestry", " and fisheries", "\u00f8kologi", "/dk/atira/pure/core/keywords/TheFacultyOfScience", "arktis", "ecology"]}, "links": [{"href": "https://doi.org/10.1016/j.apsoil.2007.12.014"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Applied%20Soil%20Ecology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.apsoil.2007.12.014", "name": "item", "description": "10.1016/j.apsoil.2007.12.014", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.apsoil.2007.12.014"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2008-07-01T00:00:00Z"}}, {"id": "10.1016/j.envexpbot.2025.106262", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:15:47Z", "type": "Journal Article", "created": "2025-10-26", "title": "Is moss-associated nitrogen fixation controlled by the same factors across shoots, species and sites?", "description": "Biological N2 fixation performed by moss-associated cyanobacteria is among the main sources of new nitrogen (N) input in pristine subarctic ecosystems. Yet, until now there has been a lack of knowledge on the drivers of biological N2 fixation on small spatial scales (moss segment) in relation to the drivers at larger scales (moisture ecosystem). To investigate this, we assessed the capacity of N2 fixation along shoots of two common moss species, Pleurozium schreberi and Hylocomium splendens, collected along a steep precipitation gradient in the Subarctic. Furthermore, concentrations of nutrients and pH were analysed along the same moss shoot-gradients. We found the highest nitrogenase activity in H. splendens collected at the location with the highest mean annual precipitation. Nitrogenase activity varied significantly along the moss shoots, and between species and location along the precipitation gradient. P. schreberi had the highest nitrogenase activity in the middle segments, while for H. splendens , it was highest in the lowest segments (below 3\u202fcm). Contents of iron, molybdenum and N generally increased with moss segment depth, but phosphorus concentrations decreased and pH was stable across segments. Taken together, the factors that drive nitrogenase activity at small scales differ between moss species, whereas precipitation predominantly controls nitrogenase activity at larger scales (across habitats).
", "keywords": ["Hylocomium splendens", "Arctic", "Nitrogen fixation", "Bryophytes", "Pleurozium schreberi", "Precipitation", "Limiting nutrients"], "contacts": [{"organization": "J\u00f8rgen Ulrik Graudal Levinsen, Mingyue Yuan, Anders Michelsen, Kathrin Rousk,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1016/j.envexpbot.2025.106262"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Environmental%20and%20Experimental%20Botany", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.envexpbot.2025.106262", "name": "item", "description": "10.1016/j.envexpbot.2025.106262", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.envexpbot.2025.106262"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2025-11-01T00:00:00Z"}}, {"id": "10449/84316", "type": "Feature", "geometry": null, "properties": {"license": "Restricted", "updated": "2026-09-22T16:22:03Z", "type": "Journal Article", "created": "2024-02-19", "title": "Novel endolithic bacteria of phylum Chloroflexota reveal a myriad of potential survival strategies in the Antarctic desert", "description": "ABSTRACTThe ice-free McMurdo Dry Valleys of Antarctica are dominated by nutrient-poor mineral soil and rocky outcrops. The principal habitat for microorganisms is within rocks (endolithic). In this environment, microorganisms are provided with protection against sub-zero temperatures, rapid thermal fluctuations, extreme dryness, and ultraviolet and solar radiation. Endolithic communities include lichen, algae, fungi, and a diverse array of bacteria. Chloroflexota is among the most abundant bacterial phyla present in these communities. Among the Chloroflexota are four novel classes of bacteria, here named Candidatus Spiritibacteria class. nov. (=UBA5177), Candidatus Martimicrobia class. nov. (=UBA4733), Candidatus Tarhunnaeia class. nov. (=UBA6077), and Candidatus Uliximicrobia class. nov. (=UBA2235). We retrieved 17 high-quality metagenome-assembled genomes (MAGs) that represent these four classes. Based on genome predictions, all these bacteria are inferred to be aerobic heterotrophs that encode enzymes for the catabolism of diverse sugars. These and other organic substrates are likely derived from lichen, algae, and fungi, as metabolites (including photosynthate), cell wall components, and extracellular matrix components. The majority of MAGs encode the capacity for trace gas oxidation using high-affinity uptake hydrogenases, which could provide energy and metabolic water required for survival and persistence. Furthermore, some MAGs encode the capacity to couple the energy generated from H 2 and CO oxidation to support carbon fixation (atmospheric chemosynthesis). All encode mechanisms for the detoxification and efflux of heavy metals. Certain MAGs encode features that indicate possible interactions with other organisms, such as Tc-type toxin complexes, hemolysins, and macroglobulins.
IMPORTANCEThe ice-free McMurdo Dry Valleys of Antarctica are the coldest and most hyperarid desert on Earth. It is, therefore, the closest analog to the surface of the planet Mars. Bacteria and other microorganisms survive by inhabiting airspaces within rocks (endolithic). We identify four novel classes of phylum Chloroflexota , and, based on interrogation of 17 metagenome-assembled genomes, we predict specific metabolic and physiological adaptations that facilitate the survival of these bacteria in this harsh environment\uffe2\uff80\uff94including oxidation of trace gases and the utilization of nutrients (including sugars) derived from lichen, algae, and fungi. We propose that such adaptations allow these endolithic bacteria to eke out an existence in this cold and extremely dry habitat.
", "keywords": ["570", "Bacteria", "Fungi", "Antarctic Regions", "Chloroflexi", "15. Life on land", "Survival strategies", "Cold Temperature", "Extremophiles", "13. Climate action", "Antarctica", "Endolithic communities", "Metagenomics", "14. Life underwater", "Sugars", "Settore BIO/19 - MICROBIOLOGIA GENERALE"]}, "links": [{"href": "https://doi.org/10449/84316"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Applied%20and%20Environmental%20Microbiology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10449/84316", "name": "item", "description": "10449/84316", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10449/84316"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2024-02-19T00:00:00Z"}}, {"id": "10.1016/j.envpol.2022.118808", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-09-22T16:15:49Z", "type": "Journal Article", "created": "2022-01-07", "title": "Microplastic variability in subsurface water from the Arctic to Antarctica", "description": "Comparative investigations of microplastic (MP) occurrence in the global ocean are often hampered by the application of different methods. In this study, the same sampling and analytical approach was applied during five different cruises to investigate MP covering a route from the East-Siberian Sea in the Arctic, through the Atlantic, and into the Antarctic Peninsula. A total of 121 subsurface water samples were collected using underway pump-through system on two different vessels. This approach allowed subsurface MP (100\u00a0\u03bcm-5\u00a0mm) to be evaluated in five regions of the World Ocean (Antarctic, Central Atlantic, North Atlantic, Barents Sea and Siberian Arctic) and to assess regional differences in MP characteristics. The average abundance of MP for whole studied area was 0.7\u00a0\u00b1\u00a00.6 items/m3 (ranging from 0 to 2.6 items/m3), with an equal average abundance for both fragments and fibers (0.34 items/m3). Although no statistical difference was found for MP abundance between the studied regions. Differences were found between the size, morphology, polymer types and weight concentrations. The Central Atlantic and Barents Sea appeared to have more MP in terms of weight concentration (7-7.5\u00a0\u03bcg/m3) than the North Atlantic and Siberian Arctic (0.6\u00a0\u03bcg/m3). A comparison of MP characteristics between the two Hemispheres appears to indicate that MP in the Northern Hemisphere mostly originate from terrestrial input, while offshore industries play an important role as a source of MP in the Southern Hemisphere. The waters of the Northern Hemisphere were found to be more polluted by fibers than those of the Southern Hemisphere. The results presented here suggest that fibers can be transported by air and water over long distances from the source, while distribution of fragments is limited mainly to the water mass where the source is located.", "keywords": ["550", "Arctic Regions", "Microplastics", "Microplastic", "Antarctic Regions", "Water", "Subsurface water", "01 natural sciences", "Global distribution", "Fibers", "Harmonization", "13. Climate action", "14. Life underwater", "Plastics", "Water Pollutants", " Chemical", "Environmental Monitoring", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1016/j.envpol.2022.118808"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Environmental%20Pollution", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.envpol.2022.118808", "name": "item", "description": "10.1016/j.envpol.2022.118808", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.envpol.2022.118808"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-04-01T00:00:00Z"}}, {"id": "10.1038/s41586-024-07274-7", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:17:08Z", "type": "Journal Article", "created": "2024-04-17", "title": "Environmental drivers of increased ecosystem respiration in a warming tundra", "description": "AbstractArctic and alpine tundra ecosystems are large reservoirs of organic carbon1,2. Climate warming may stimulate ecosystem respiration and release carbon into the atmosphere3,4. The magnitude and persistency of this stimulation and the environmental mechanisms that drive its variation remain uncertain5\uffe2\uff80\uff937. This hampers the accuracy of global land carbon\uffe2\uff80\uff93climate feedback projections7,8. Here we synthesize 136 datasets from 56 open-top chamber in situ warming experiments located at 28 arctic and alpine tundra sites which have been running for less than 1\uffe2\uff80\uff89year up to 25\uffe2\uff80\uff89years. We show that a mean rise of 1.4\uffe2\uff80\uff89\uffc2\uffb0C [confidence interval (CI) 0.9\uffe2\uff80\uff932.0\uffe2\uff80\uff89\uffc2\uffb0C] in air and 0.4\uffe2\uff80\uff89\uffc2\uffb0C [CI 0.2\uffe2\uff80\uff930.7\uffe2\uff80\uff89\uffc2\uffb0C] in soil temperature results in an increase in growing season ecosystem respiration by 30% [CI 22\uffe2\uff80\uff9338%] (n\uffe2\uff80\uff89=\uffe2\uff80\uff89136). Our findings indicate that the stimulation of ecosystem respiration was due to increases in both plant-related and microbial respiration (n\uffe2\uff80\uff89=\uffe2\uff80\uff899) and continued for at least 25\uffe2\uff80\uff89years (n\uffe2\uff80\uff89=\uffe2\uff80\uff89136). The magnitude of the warming effects on respiration was driven by variation in warming-induced changes in local soil conditions, that is, changes in total nitrogen concentration and pH and by context-dependent spatial variation in these conditions, in particular total nitrogen concentration and the carbon:nitrogen ratio. Tundra sites with stronger nitrogen limitations and sites in which warming had stimulated plant and microbial nutrient turnover seemed particularly sensitive in their respiration response to warming. The results highlight the importance of local soil conditions and warming-induced changes therein for future climatic impacts on respiration.Ongoing permafrost thaw in the Arctic may remobilize large amounts of old organic matter. Upon transport to the Siberian shelf seas, this material may be degraded and released to the atmosphere, exported off\uffe2\uff80\uff90shelf, or buried in the sediments. While our understanding of the fate of permafrost\uffe2\uff80\uff90derived organic matter in shelf waters is improving, poor constraints remain regarding degradation in sediments. Here we use an extensive data set of organic carbon concentrations and isotopes (n\uffc2\uffa0=\uffc2\uffa0109) to inventory terrigenous organic carbon (terrOC) in surficial sediments of the Laptev and East Siberian Seas (LS\uffc2\uffa0+\uffc2\uffa0ESS). Of these ~2.7 Tg terrOC about 55% appear resistant to degradation on a millennial timescale. A first\uffe2\uff80\uff90order degradation rate constant of 1.5\uffc2\uffa0kyr\uffe2\uff88\uff921 is derived by combining a previously established relationship between water depth and cross\uffe2\uff80\uff90shelf sediment\uffe2\uff80\uff90terrOC transport time with mineral\uffe2\uff80\uff90associated terrOC loadings. This yields a terrOC degradation flux of ~1.7\uffc2\uffa0Gg/year from surficial sediments during cross\uffe2\uff80\uff90shelf transport, which is orders of magnitude lower than earlier estimates for degradation fluxes of dissolved and particulate terrOC in the water column of the LS\uffc2\uffa0+\uffc2\uffa0ESS. The difference is mainly due to the low degradation rate constant of sedimentary terrOC, likely caused by a combination of factors: (i) the lower availability of oxygen in the sediments compared to fully oxygenated waters, (ii) the stabilizing role of terrOC\uffe2\uff80\uff90mineral associations, and (iii) the higher proportion of material that is intrinsically recalcitrant due to its chemical/molecular structure in sediments. Sequestration of permafrost\uffe2\uff80\uff90released terrOC in shelf sediments may thereby attenuate the otherwise expected permafrost carbon\uffe2\uff80\uff90climate feedback.Ongoing rapid arctic warming leads to extensive permafrost thaw, which in turn increases the hydrologic connectivity of the landscape by opening up subsurface flow paths. Suspended particulate organic matter (POM) has proven useful to trace permafrost thaw signals in arctic rivers, which may experience higher organic matter loads in the future due to expansion and increasing intensity of thaw processes such as thermokarst and river bank erosion. Here we focus on the Kolyma River watershed in Northeast Siberia, the world's largest watershed entirely underlain by continuous permafrost. To evaluate and characterize the present\uffe2\uff80\uff90day fluvial release of POM from permafrost thaw, we collected water samples every 4\uffe2\uff80\uff937 days during the 4\uffe2\uff80\uff90month open water season in 2013 and 2015 from the lower Kolyma River mainstem and from a small nearby headwater stream (Y3) draining an area completely underlain by Yedoma permafrost (Pleistocene ice\uffe2\uff80\uff90 and organic\uffe2\uff80\uff90rich deposits). Concentrations of particulate organic carbon generally followed the hydrograph with the highest concentrations during the spring flood in late May/early June. For the Kolyma River, concentrations of dissolved organic carbon showed a similar behavior, in contrast to the headwater stream, where dissolved organic carbon values were generally higher and particulate organic carbon concentrations lower than for Kolyma. Carbon isotope analysis (\uffce\uffb413C, \uffce\uff9414C) suggested Kolyma\uffe2\uff80\uff90POM to stem from both contemporary and older permafrost sources, while Y3\uffe2\uff80\uff90POM was more strongly influenced by in\uffe2\uff80\uff90stream production and recent vegetation. Lipid biomarker concentrations (high\uffe2\uff80\uff90molecular\uffe2\uff80\uff90weight n\uffe2\uff80\uff90alkanoic acids and n\uffe2\uff80\uff90alkanes) did not display clear seasonal patterns, yet implied Y3\uffe2\uff80\uff90POM to be more degraded than Kolyma\uffe2\uff80\uff90POM.Rock-dwelling microorganisms are key players in ecosystem functioning of Antarctic ice free-areas. Yet, little is known about their diversity and ecology. Here, we performed metagenomic analyses on rocks from across Antarctica comprising >75,000 viral operational taxonomic units (vOTUS). We found largely undescribed, highly diverse and spatially structured virus communities potentially influencing bacterial adaptation and biogeochemistry. This catalog lays the foundation for expanding knowledge of the virosphere in extreme environments.Extreme weather events can have strong negative impacts on species survival and community structure when surpassing lethal thresholds. Extreme, short\uffe2\uff80\uff90lived, winter warming events in the Arctic rapidly melt snow and expose ecosystems to unseasonably warm air (for instance, 2\uffe2\uff80\uff9310\uffe2\uff80\uff83\uffc2\uffb0C for 2\uffe2\uff80\uff9314 days) but upon return to normal winter climate exposes the ecosystem to much colder temperatures due to the loss of insulating snow. Single events have been shown to reduce plant reproduction and increase shoot mortality, but impacts of multiple events are little understood as are the broader impacts on community structure, growth, carbon balance, and nutrient cycling. To address these issues, we simulated week\uffe2\uff80\uff90long extreme winter warming events \uffe2\uff80\uff93 using infrared heating lamps and soil warming cables \uffe2\uff80\uff93 for 3 consecutive years in a sub\uffe2\uff80\uff90Arctic heathland dominated by the dwarf shrubsEmpetrum hermaphroditum, Vaccinium vitis\uffe2\uff80\uff90idaea(both evergreen) andVaccinium myrtillus(deciduous). During the growing seasons after the second and third winter event, spring bud burst was delayed by up to a week forE. hermaphroditumandV. myrtillus, and berry production reduced by 11\uffe2\uff80\uff9375% and 52\uffe2\uff80\uff9395% forE. hermaphroditumandV. myrtillus, respectively. Greater shoot mortality occurred inE. hermaphroditum(up to 52%),V. vitis\uffe2\uff80\uff90idaea(51%), andV. myrtillus(80%). Root growth was reduced by more than 25% but soil nutrient availability remained unaffected. Gross primary productivity was reduced by more than 50% in the summer following the third simulation. Overall, the extent of damage was considerable, and critically plant responses were opposite in direction to the increased growth seen in long\uffe2\uff80\uff90term summer warming simulations and the \uffe2\uff80\uff98greening\uffe2\uff80\uff99 seen for some arctic regions. Given the Arctic is warming more in winter than summer, and extreme events are predicted to become more frequent, this generates large uncertainty in our current understanding of arctic ecosystem responses to climate change.
", "keywords": ["flowering phenology", "0106 biological sciences", "extreme events", "climate change", "13. Climate action", "arctic", "winter warming", "nutrient cycling", "GPP", "15. Life on land", "dwarf shrub", "01 natural sciences", "SDG 15 - Life on Land"]}, "links": [{"href": "https://doi.org/10.1111/j.1365-2486.2011.02424.x"}, {"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/j.1365-2486.2011.02424.x", "name": "item", "description": "10.1111/j.1365-2486.2011.02424.x", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/j.1365-2486.2011.02424.x"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2011-04-13T00:00:00Z"}}, {"id": "10.1890/es13-00281.1", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-09-22T16:18:42Z", "type": "Journal Article", "created": "2014-06-19", "title": "Long-Term Experimental Warming And Nutrient Additions Increase Productivity In Tall Deciduous Shrub Tundra", "description": "Warming Arctic temperatures can drive changes in vegetation structure and function directly by stimulating plant growth or indirectly by stimulating microbial decomposition of organic matter and releasing more nutrients for plant uptake and growth. The arctic biome is currently increasing in deciduous shrub cover and this increase is expected to continue with climate warming. However, little is known how current deciduous shrub communities will respond to future climate induced warming and nutrient increase. We examined the plant and ecosystem response to a long\uffe2\uff80\uff90term (18 years) nutrient addition and warming experiment in an Alaskan arctic tall deciduous shrub tundra ecosystem to understand controls over plant productivity and carbon (C) and nitrogen (N) storage in shrub tundra ecosystems. In addition, we used a meta\uffe2\uff80\uff90analysis approach to compare the treatment effect size for aboveground biomass among seven long\uffe2\uff80\uff90term studies conducted across multiple plant community types within the Arctic. We found that biomass, productivity, and aboveground N pools increased with nutrient additions and warming, while species diversity decreased. Both nutrient additions and warming caused the dominant functional group, deciduous shrubs, to increase biomass and proportional C and N allocation to aboveground stems but decreased allocation to belowground stems. For all response variables except soil C and N pools, effects of nutrients plus warming were largest. Soil C and N pools were highly variable and we could not detect any response to the treatments. The biomass response to warming and fertilization in tall deciduous shrub tundra was greater than moist acidic and moist non\uffe2\uff80\uff90acidic tundra and more similar to the biomass response of wet sedge tundra. Our data suggest that in a warmer and more nutrient\uffe2\uff80\uff90rich Arctic, tall deciduous shrub tundra will have greater total deciduous shrub biomass and a higher proportion of woody tissue that has a longer residence time, with a lower proportion of C and N allocated to belowground stems.
", "keywords": ["580", "0106 biological sciences", "Nitrogen pools", "Carbon pools", "15. Life on land", "01 natural sciences", "Deciduous shrubs", "Meta-analysis", "Arctic", "Manipulated warming", "13. Climate action", "11. Sustainability", "Climate change", "Nutrient additions", "Tundra", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1890/es13-00281.1"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Ecosphere", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1890/es13-00281.1", "name": "item", "description": "10.1890/es13-00281.1", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1890/es13-00281.1"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2014-06-01T00:00:00Z"}}, {"id": "10.1029/2021jg006688", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-09-22T16:17:02Z", "type": "Journal Article", "created": "2022-06-11", "title": "Bidirectional Exchange of Biogenic Volatile Organic Compounds in Subarctic Heath Mesocosms During Autumn Climate Scenarios", "description": "AbstractBiogenic volatile organic compound (BVOC) flux dynamics during the subarctic autumn are largely unexplored and have been considered insignificant due to the relatively low biological activity expected during autumn. Here, we exposed subarctic heath ecosystems to predicted future autumn climate scenarios (ambient, warming, and colder, dark conditions), changes in light availability, and flooding, to mimic the more extreme rainfall or snowmelt events expected in the future. We used climate chambers to measure the net ecosystem fluxes and bidirectional exchange of BVOCs from intact heath mesocosms using a dynamic enclosure technique coupled to a proton\uffe2\uff80\uff90transfer\uffe2\uff80\uff90reaction time\uffe2\uff80\uff90of\uffe2\uff80\uff90flight mass spectrometer (PTR\uffe2\uff80\uff93ToF\uffe2\uff80\uff93MS). We focused on six BVOCs (methanol, acetic acid, acetaldehyde, acetone, isoprene, and monoterpenes) that were among the most dominant and that were previously identified in arctic tundra ecosystems. Warming increased ecosystem respiration and resulted in either net BVOC release or increased uptake compared to the ambient scenario. None of the targeted BVOCs showed net release in the cold and dark scenario. Acetic acid exhibited significantly lower net uptake in the cold and dark scenario than in the ambient scenario, which suggests reduced microbial activity. Flooding was characterized by net uptake of the targeted BVOCs and overruled any temperature effects conferred by the climate scenarios. Monoterpenes were mainly taken up by the mesocosms and their fluxes were not affected by the climate scenarios or flooding. This study shows that although autumn BVOC fluxes on a subarctic heath are generally low, changes in future climate may strongly modify them.
", "keywords": ["LITTER", "volatile organic compound", "FLUXES", "flooding", "Arctic", "Flooding", "Autumn", "11. Sustainability", "arctic", "autumn", "Ecosystem-atmosphere interactions", "Global change", "global change", "EMISSIONS", "MICROBIAL ACTIVITY", "ecosystem-atmosphere interactions", "Volatile organic compound", "15. Life on land", "FOREST", "TUNDRA", "SOIL", "NITROGEN", "SUMMER", "13. Climate action", "WINTER", "Research Article"]}, "links": [{"href": "https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2021JG006688"}, {"href": "https://doi.org/10.1029/2021jg006688"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Journal%20of%20Geophysical%20Research%3A%20Biogeosciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1029/2021jg006688", "name": "item", "description": "10.1029/2021jg006688", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1029/2021jg006688"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2022-06-01T00:00:00Z"}}, {"id": "10.1029/2020gl088561", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-22T16:17:01Z", "type": "Journal Article", "created": "2020-07-17", "title": "Nearshore Zone Dynamics Determine Pathway of Organic Carbon From Eroding Permafrost Coasts", "description": "AbstractCollapse of permafrost coasts delivers large quantities of particulate organic carbon (POC) to Arctic coastal areas. With rapidly changing environmental conditions, sediment and organic carbon (OC) mobilization and transport pathways are also changing. Here, we assess the sources and sinks of POC in the highly dynamic nearshore zone of Herschel Island\uffe2\uff80\uff90Qikiqtaruk (Yukon, Canada). Our results show that POC concentrations sharply decrease, from 15.9 to 0.3\uffc2\uffa0mg\uffc2\uffa0L\uffe2\uff88\uff921, within the first 100\uffe2\uff80\uff93300\uffc2\uffa0m offshore. Simultaneously, radiocarbon ages of POC drop from 16,400 to 3,600 14C years, indicating rapid settling of old permafrost POC to underlying sediments. This suggests that permafrost OC is, apart from a very narrow resuspension zone (<5\uffc2\uffa0m water depth), predominantly deposited in nearshore sediments. While long\uffe2\uff80\uff90term storage of permafrost OC in marine sediments potentially limits biodegradation and its subsequent release as greenhouse gas, resuspension of fine\uffe2\uff80\uff90grained, OC\uffe2\uff80\uff90rich sediments in the nearshore zone potentially enhances OC turnover.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.Continental margins receive, process and sequester most of the terrestrial organic carbon (terrOC) released into the ocean. In the Arctic, increasing fluvial discharge and collapsing permafrost are expected to enhance terrOC release and degradation, leading to ocean acidification and translocated CO2 release to the atmosphere. However, the processes controlling terrOC transport beyond the continental shelf, and the amount of terrOC that reaches the slope and the rise are poorly described. Here we study terrOC transport to the Laptev Sea continental slope and rise by probing surface sediments with dual\uffe2\uff80\uff90isotope (\uffce\uffb413C/\uffce\uff9414C) source apportionment, degradation\uffe2\uff80\uff90diagnostic terrestrial biomarkers (n\uffe2\uff80\uff90alkanes, n\uffe2\uff80\uff90alkanoic acids, lignin phenols) and 210Pbxs\uffe2\uff80\uff90based mass accumulation rates (MAR). The MAR\uffe2\uff80\uff90terrOC (g\uffc2\uffa0m\uffe2\uff88\uff922\uffc2\uffa0yr\uffe2\uff88\uff921) decrease from 14.7\uffc2\uffa0\uffc2\uffb1\uffc2\uffa012.2 on the shelf, to 7.0\uffc2\uffa0\uffc2\uffb1\uffc2\uffa05.8 over the slope, to 2.3\uffc2\uffa0\uffc2\uffb1\uffc2\uffa00.3 for the rise. Scaling this to the respective regimes yields that 80% of the terrOC accumulates on the shelf, while 11% and 9% of the accumulation occurs in slope and rise sediments, respectively. TerrOC remineralization is evidenced by biomarker degradation proxies (CPI of n\uffe2\uff80\uff90alkanes and 3,5Bd/V) indicating 40% and 60% more terrOC degradation from slope to rise, consistent with a decline in terrOC concentrations by 57%. TerrOC degradation only partially explains this decline. An updated Laptev Sea terrOC budget suggests that sediment transport dynamics such as turbidity currents may drive terrOC shelf\uffe2\uff80\uff90basin export, contributing to the observed accumulation pattern. This study quantitatively demonstrates that Arctic shelf seas are key receptor systems for remobilized terrOC, emphasizing their importance in the carbon cycle of the rapidly changing Arctic.