Quantifying the upper limit of stable soil carbon storage is essential for guiding policies to increase soil carbon storage. One pool of carbon considered particularly stable across climate zones and soil types is formed when dissolved organic carbon sorbs to minerals. We quantified, for the first time, the potential of mineral soils to sorb additional dissolved organic carbon (DOC) for six soil orders. We compiled 402 laboratory sorption experiments to estimate the additional DOC sorption potential, that is the potential of excess DOC sorption in addition to the existing background level already sorbed in each soil sample. We estimated this potential using gridded climate and soil geochemical variables within a machine learning model. We find that mid- and low-latitude soils and subsoils have a greater capacity to store DOC by sorption compared to high-latitude soils and topsoils. The global additional DOC sorption potential for six soil orders is estimated to be 107 $$ pm$$ \uffc2\uffb1 13 Pg C to 1\uffc2\uffa0m depth. If this potential was realized, it would represent a 7% increase in the existing total carbon stock.Permafrost degradation is delivering bioavailable dissolved organic matter (DOM) and inorganic nutrients to surface water networks. While these permafrost subsidies represent a small portion of total fluvial DOM and nutrient fluxes, they could influence food webs and net ecosystem carbon balance via priming or nutrient effects that destabilize background DOM. We investigated how addition of biolabile carbon (acetate) and inorganic nutrients (nitrogen and phosphorus) affected DOM decomposition with 28\uffe2\uff80\uff90day incubations. We incubated late\uffe2\uff80\uff90summer stream water from 23 locations nested in seven northern or high\uffe2\uff80\uff90altitude regions in Asia, Europe, and North America. DOM loss ranged from 3% to 52%, showing a variety of longitudinal patterns within stream networks. DOM optical properties varied widely, but DOM showed compositional similarity based on Fourier transform ion cyclotron resonance mass spectrometry (FT\uffe2\uff80\uff90ICR MS) analysis. Addition of acetate and nutrients decreased bulk DOM mineralization (i.e., negative priming), with more negative effects on biodegradable DOM but neutral or positive effects on stable DOM. Unexpectedly, acetate and nutrients triggered breakdown of colored DOM (CDOM), with median decreases of 1.6% in the control and 22% in the amended treatment. Additionally, the uptake of added acetate was strongly limited by nutrient availability across sites. These findings suggest that biolabile DOM and nutrients released from degrading permafrost may decrease background DOM mineralization but alter stoichiometry and light conditions in receiving waterbodies. We conclude that priming and nutrient effects are coupled in northern aquatic ecosystems and that quantifying two\uffe2\uff80\uff90way interactions between DOM properties and environmental conditions could resolve conflicting observations about the drivers of DOM in permafrost zone waterways.
", "keywords": ["0106 biological sciences", "550", "permafrost regions", "thermokarst", "vaikutukset", "ta1171", "geosciences", "ikirouta", "carbon cycling", "551", "ravinteet", "01 natural sciences", "nutrients", "cryosphere and high-latitude processes", "Biology", "Research Articles", "organic matter", "0105 earth and related environmental sciences", "compositional similarities", "nutrients and nutrient cycling", "hiilen kierto", "ravinteiden kierr\u00e4tys", "15. Life on land", "rivers", "6. Clean water", "nutrient effects", "13. Climate action", "orgaaninen aines", "1171 Geotieteet", "SDG 6 - Clean Water and Sanitation", "joet", "permafrost"]}, "links": [{"href": "https://digitalcommons.usu.edu/context/biology_facpub/article/2820/viewcontent/2020GB006719.pdf"}, {"href": "https://doi.org/10.1029/2020gb006719"}, {"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": "10.1029/2020gb006719", "name": "item", "description": "10.1029/2020gb006719", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1029/2020gb006719"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2021-01-01T00:00:00Z"}}, {"id": "10.1111/gcb.16394", "type": "Feature", "geometry": null, "properties": {"updated": "2026-06-23T16:19:27Z", "type": "Journal Article", "created": "2022-08-17", "title": "Lowering water table reduces carbon sink strength and carbon stocks in northern peatlands", "description": "AbstractPeatlands at high latitudes have accumulated >400\uffe2\uff80\uff89Pg carbon (C) because saturated soil and cold temperatures suppress C decomposition. This substantial amount of C in Arctic and Boreal peatlands is potentially subject to increased decomposition if the water table (WT) decreases due to climate change, including permafrost thaw\uffe2\uff80\uff90related drying. Here, we optimize a version of the Organizing Carbon and Hydrology In Dynamic Ecosystems model (ORCHIDEE\uffe2\uff80\uff90PCH4) using site\uffe2\uff80\uff90specific observations to investigate changes in CO2 and CH4 fluxes as well as C stock responses to an experimentally manipulated decrease of WT at six northern peatlands. The unmanipulated control peatlands, with the WT <20\uffe2\uff80\uff89cm on average (seasonal max up to 45\uffe2\uff80\uff89cm) below the surface, currently act as C sinks in most years (58\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff8934\uffe2\uff80\uff89g C\uffe2\uff80\uff89m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921; including 6\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff897\uffe2\uff80\uff89g C\uffe2\uff80\uff93CH4 m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921 emission). We found, however, that lowering the WT by 10\uffe2\uff80\uff89cm reduced the CO2 sink by 13\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff8915\uffe2\uff80\uff89g\uffe2\uff80\uff89C\uffe2\uff80\uff89m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921 and decreased CH4 emission by 4\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff894\uffe2\uff80\uff89g CH4 m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921, thus accumulating less C over 100\uffe2\uff80\uff89years (0.2\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff890.2\uffe2\uff80\uff89kg\uffe2\uff80\uff89C\uffe2\uff80\uff89m\uffe2\uff88\uff922). Yet, the reduced emission of CH4, which has a larger greenhouse warming potential, resulted in a net decrease in greenhouse gas balance by 310\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff89360\uffe2\uff80\uff89g\uffe2\uff80\uff89CO2\uffe2\uff80\uff90eq\uffc2\uffa0m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921. Peatlands with the initial WT close to the soil surface were more vulnerable to C loss: Non\uffe2\uff80\uff90permafrost peatlands lost >2\uffe2\uff80\uff89kg\uffe2\uff80\uff89C\uffe2\uff80\uff89m\uffe2\uff88\uff922 over 100\uffe2\uff80\uff89years when WT is lowered by 50\uffe2\uff80\uff89cm, while permafrost peatlands temporally switched from C sinks to sources. These results highlight that reductions in C storage capacity in response to drying of northern peatlands are offset in part by reduced CH4 emissions, thus slightly reducing the positive carbon climate feedbacks of peatlands under a warmer and drier future climate scenario.Quantifying the upper limit of stable soil carbon storage is essential for guiding policies to increase soil carbon storage. One pool of carbon considered particularly stable across climate zones and soil types is formed when dissolved organic carbon sorbs to minerals. We quantified, for the first time, the potential of mineral soils to sorb additional dissolved organic carbon (DOC) for six soil orders. We compiled 402 laboratory sorption experiments to estimate the additional DOC sorption potential, that is the potential of excess DOC sorption in addition to the existing background level already sorbed in each soil sample. We estimated this potential using gridded climate and soil geochemical variables within a machine learning model. We find that mid- and low-latitude soils and subsoils have a greater capacity to store DOC by sorption compared to high-latitude soils and topsoils. The global additional DOC sorption potential for six soil orders is estimated to be 107 $$ pm$$ \uffc2\uffb1 13 Pg C to 1\uffc2\uffa0m depth. If this potential was realized, it would represent a 7% increase in the existing total carbon stock.Peatlands at high latitudes have accumulated >400\uffe2\uff80\uff89Pg carbon (C) because saturated soil and cold temperatures suppress C decomposition. This substantial amount of C in Arctic and Boreal peatlands is potentially subject to increased decomposition if the water table (WT) decreases due to climate change, including permafrost thaw\uffe2\uff80\uff90related drying. Here, we optimize a version of the Organizing Carbon and Hydrology In Dynamic Ecosystems model (ORCHIDEE\uffe2\uff80\uff90PCH4) using site\uffe2\uff80\uff90specific observations to investigate changes in CO2 and CH4 fluxes as well as C stock responses to an experimentally manipulated decrease of WT at six northern peatlands. The unmanipulated control peatlands, with the WT <20\uffe2\uff80\uff89cm on average (seasonal max up to 45\uffe2\uff80\uff89cm) below the surface, currently act as C sinks in most years (58\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff8934\uffe2\uff80\uff89g C\uffe2\uff80\uff89m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921; including 6\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff897\uffe2\uff80\uff89g C\uffe2\uff80\uff93CH4 m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921 emission). We found, however, that lowering the WT by 10\uffe2\uff80\uff89cm reduced the CO2 sink by 13\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff8915\uffe2\uff80\uff89g\uffe2\uff80\uff89C\uffe2\uff80\uff89m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921 and decreased CH4 emission by 4\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff894\uffe2\uff80\uff89g CH4 m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921, thus accumulating less C over 100\uffe2\uff80\uff89years (0.2\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff890.2\uffe2\uff80\uff89kg\uffe2\uff80\uff89C\uffe2\uff80\uff89m\uffe2\uff88\uff922). Yet, the reduced emission of CH4, which has a larger greenhouse warming potential, resulted in a net decrease in greenhouse gas balance by 310\uffe2\uff80\uff89\uffc2\uffb1\uffe2\uff80\uff89360\uffe2\uff80\uff89g\uffe2\uff80\uff89CO2\uffe2\uff80\uff90eq\uffc2\uffa0m\uffe2\uff88\uff922\uffc2\uffa0year\uffe2\uff88\uff921. Peatlands with the initial WT close to the soil surface were more vulnerable to C loss: Non\uffe2\uff80\uff90permafrost peatlands lost >2\uffe2\uff80\uff89kg\uffe2\uff80\uff89C\uffe2\uff80\uff89m\uffe2\uff88\uff922 over 100\uffe2\uff80\uff89years when WT is lowered by 50\uffe2\uff80\uff89cm, while permafrost peatlands temporally switched from C sinks to sources. These results highlight that reductions in C storage capacity in response to drying of northern peatlands are offset in part by reduced CH4 emissions, thus slightly reducing the positive carbon climate feedbacks of peatlands under a warmer and drier future climate scenario.Quantifying the upper limit of stable soil carbon storage is essential for guiding policies to increase soil carbon storage. One pool of carbon considered particularly stable across climate zones and soil types is formed when dissolved organic carbon sorbs to minerals. We quantified, for the first time, the potential of mineral soils to sorb additional dissolved organic carbon (DOC) for six soil orders. We compiled 402 laboratory sorption experiments to estimate the additional DOC sorption potential, that is the potential of excess DOC sorption in addition to the existing background level already sorbed in each soil sample. We estimated this potential using gridded climate and soil geochemical variables within a machine learning model. We find that mid- and low-latitude soils and subsoils have a greater capacity to store DOC by sorption compared to high-latitude soils and topsoils. The global additional DOC sorption potential for six soil orders is estimated to be 107 $$ pm$$ \uffc2\uffb1 13 Pg C to 1\uffc2\uffa0m depth. If this potential was realized, it would represent a 7% increase in the existing total carbon stock.