{"type": "FeatureCollection", "features": [{"id": "10.1016/j.soilbio.2004.08.013", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-21T16:16:09Z", "type": "Journal Article", "created": "2004-09-30", "title": "Decomposition Of C-14-Labeled Roots In A Pasture Soil Exposed To 10 Years Of Elevated Co2", "description": "Abstract   The net flux of soil C is determined by the balance between soil C input and microbial decomposition, both of which might be altered under prolonged elevated atmospheric CO 2 . In this study, we determined the effect of elevated CO 2  on decomposition of grass root material ( Lolium perenne  L.).  14 C-labeled root material, produced under ambient (35\u00a0Pa pCO 2 ) or elevated CO 2  (70\u00a0Pa pCO 2 ) was incubated in soil for 64 days. The soils were taken from a pasture ecosystem which had been exposed to ambient (35\u00a0Pa pCO 2 ) or elevated CO 2  (60\u00a0Pa pCO 2 ) under FACE-conditions for 10 years and two fertilizer N rates: 140 and 560\u00a0kg N ha \u22121 \u00a0year \u22121 . In soil exposed to elevated CO 2 , decomposition rates of root material grown at either ambient or elevated CO 2  were always lower than in the control soil exposed to ambient CO 2 , demonstrating a change in microbial activity. In the soil that received the high rate of N fertilizer, decomposition of root material grown at elevated CO 2  decreased by approximately 17% after incubation for 64 days compared to root material grown at ambient CO 2 . The amount of  14 CO 2  respired per amount of  14 C incorporated in the microbial biomass ( q  14 CO 2 ) was significantly lower when roots were grown under high CO 2  compared to roots grown under low CO 2 . We hypothesize that this decrease is the result of a shift in the microbial community, causing an increase in metabolic efficiency. Soils exposed to elevated CO 2  tended to respire more native SOC, both with and without the addition of the root material, probably resulting from a higher C supply to the soil during the 10 years of treatment with elevated CO 2 . The results show the importance of using soils adapted to elevated CO 2  in studies of decomposition of roots grown under elevated CO 2 . Our results further suggest that negative priming effects may obscure CO 2  data in incubation experiments with unlabeled substrates. From the results obtained, we conclude that a slower turnover of root material grown in an \u2018elevated-CO 2  world\u2019 may result in a limited net increase in C storage in ryegrass swards.", "keywords": ["organic-matter dynamics", "2. Zero hunger", "microbial biomass", "atmospheric carbon-dioxide", "turnover", "fine roots", "04 agricultural and veterinary sciences", "15. Life on land", "01 natural sciences", "forest soils", "tallgrass prairie", "trifolium-repens l", "lolium-perenne", "litter quality", "0401 agriculture", " forestry", " and fisheries", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1016/j.soilbio.2004.08.013"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Soil%20Biology%20and%20Biochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1016/j.soilbio.2004.08.013", "name": "item", "description": "10.1016/j.soilbio.2004.08.013", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1016/j.soilbio.2004.08.013"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2005-03-01T00:00:00Z"}}, {"id": "10.1073/pnas.0706518104", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-21T16:17:01Z", "type": "Journal Article", "created": "2007-08-21", "title": "Increases In Nitrogen Uptake Rather Than Nitrogen-Use Efficiency Support Higher Rates Of Temperate Forest Productivity Under Elevated Co2", "description": "<p>             Forest ecosystems are important sinks for rising concentrations of atmospheric CO             2             . In previous research, we showed that net primary production (NPP) increased by 23 \uffc2\uffb1 2% when four experimental forests were grown under atmospheric concentrations of CO             2             predicted for the latter half of this century. Because nitrogen (N) availability commonly limits forest productivity, some combination of increased N uptake from the soil and more efficient use of the N already assimilated by trees is necessary to sustain the high rates of forest NPP under free-air CO             2             enrichment (FACE). In this study, experimental evidence demonstrates that the uptake of N increased under elevated CO             2             at the Rhinelander, Duke, and Oak Ridge National Laboratory FACE sites, yet fertilization studies at the Duke and Oak Ridge National Laboratory FACE sites showed that tree growth and forest NPP were strongly limited by N availability. By contrast, nitrogen-use efficiency increased under elevated CO             2             at the POP-EUROFACE site, where fertilization studies showed that N was not limiting to tree growth. Some combination of increasing fine root production, increased rates of soil organic matter decomposition, and increased allocation of carbon (C) to mycorrhizal fungi is likely to account for greater N uptake under elevated CO             2             . Regardless of the specific mechanism, this analysis shows that the larger quantities of C entering the below-ground system under elevated CO             2             result in greater N uptake, even in N-limited ecosystems. Biogeochemical models must be reformulated to allow C transfers below ground that result in additional N uptake under elevated CO             2             .           </p>", "keywords": ["rotation poplar plantation", "0106 biological sciences", "Nitrogen", "Climate", "atmospheric carbon-dioxide", "enrichment face", "organic nitrogen", "Biological Transport", "deciduous forest", "04 agricultural and veterinary sciences", "Carbon Dioxide", "15. Life on land", "01 natural sciences", "Trees", "Kinetics", "13. Climate action", "0401 agriculture", " forestry", " and fisheries", "populus-tremuloides", "community composition", "soil-n availability", "fine-root production", "Ecosystem", "ecosystem responses"]}, "links": [{"href": "https://doi.org/10.1073/pnas.0706518104"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Proceedings%20of%20the%20National%20Academy%20of%20Sciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1073/pnas.0706518104", "name": "item", "description": "10.1073/pnas.0706518104", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1073/pnas.0706518104"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2007-08-28T00:00:00Z"}}, {"id": "10.1029/2002gb001886", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-21T16:16:39Z", "type": "Journal Article", "created": "2003-06-16", "title": "Effects Of Elevated Co2 And N Deposition On Ch4 Emissions From European Mires", "description": "<p>Methane fluxes were measured at five sites representing oligotrophic peatlands along a European transect. Five study plots were subjected to elevated CO2 concentration (560 ppm), and five plots to NH4NO3 (3 or 5 g N yr\uffe2\uff88\uff921). The CH4 emissions from the control plots correlated in most cases with the soil temperatures. The depth of the water table, the pH, and the DOC, N and SO4 concentrations were only weakly correlated with the CH4 emissions. The elevated CO2 treatment gave nonsignificantly higher CH4 emissions at three sites and lower at two sites. The N treatment resulted in higher methane emissions at three sites (nonsignificant). At one site, the CH4 fluxes of the N\uffe2\uff80\uff90treatment plots were significantly lower than those of the control plots. These results were not in agreement with our hypotheses, nor with the results obtained in some earlier studies. However, the results are consistent with the results of the vegetation analyses, which showed no significant treatment effects on species relationships or biomass production.</p>", "keywords": ["northern peatlands", "methane emissions", "atmospheric carbon-dioxide", "temperature", "04 agricultural and veterinary sciences", "15. Life on land", "01 natural sciences", "6. Clean water", "forest soils", "nitrogen deposition", "boreal mire", "13. Climate action", "raised co2", "0401 agriculture", " forestry", " and fisheries", "bog vegetation", "water-table", "0105 earth and related environmental sciences"]}, "links": [{"href": "https://doi.org/10.1029/2002gb001886"}, {"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": "10.1029/2002gb001886", "name": "item", "description": "10.1029/2002gb001886", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1029/2002gb001886"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2003-06-01T00:00:00Z"}}, {"id": "10.1098/rstb.2017.0408", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-21T16:17:21Z", "type": "Journal Article", "created": "2018-10-08", "title": "Widespread reduction in sun-induced fluorescence from the Amazon during the 2015/2016 El Ni\u00f1o", "description": "<p>             The tropical carbon balance dominates year-to-year variations in the CO             2             exchange with the atmosphere through photosynthesis, respiration and fires. Because of its high correlation with gross primary productivity (GPP), observations of sun-induced fluorescence (SIF) are of great interest. We developed a new remotely sensed SIF product with improved signal-to-noise in the tropics, and use it here to quantify the impact of the 2015/2016 El Ni\uffc3\uffb1o\uffc2\uffa0Amazon drought. We find that SIF was strongly suppressed over areas with anomalously high temperatures and decreased levels of water in the soil. SIF went below its climatological range starting from the end of the 2015 dry season (October) and returned to normal levels by February 2016 when atmospheric conditions returned to normal, but well before the end of anomalously low precipitation that persisted through June 2016. Impacts were not uniform across the Amazon basin, with the eastern part experiencing much larger (10\uffe2\uff80\uff9315%) SIF reductions than the western part of the basin (2\uffe2\uff80\uff935%). We estimate the integrated loss of GPP relative to eight previous years to be 0.34\uffe2\uff80\uff930.48 PgC in the three-month period October\uffe2\uff80\uff93November\uffe2\uff80\uff93December 2015.           </p>           <p>This article is part of a discussion meeting issue \uffe2\uff80\uff98The impact of the 2015/2016 El Ni\uffc3\uffb1o on the terrestrial tropical carbon cycle: patterns, mechanisms and implications\uffe2\uff80\uff99.</p>", "keywords": ["0301 basic medicine", "FLUXES", "El Ni\u00f1o-Southern Oscillation", "Amazon rainforest", "sun-induced fluorescence", "El Ni\u00f1o Southern Oscillation", "drought response", "Forests", "SOUTHERN-OSCILLATION", "01 natural sciences", "Fluorescence", "Trees", "SCIAMACHY", "03 medical and health sciences", "GOME-2", "ATMOSPHERIC CARBON-DIOXIDE", "SATELLITE", "0105 earth and related environmental sciences", "El Nino-Southern Oscillation", "Amazone rainforest", "Articles", "15. Life on land", "tropical terrestrial carbon cycle", "gross primary production", "TERRESTRIAL CHLOROPHYLL FLUORESCENCE", "SIMULATIONS", "6. Clean water", "Droughts", "CLIMATE", "13. Climate action", "BALANCE", "Remote Sensing Technology", "Sunlight", "Brazil"]}, "links": [{"href": "https://royalsocietypublishing.org/doi/pdf/10.1098/rstb.2017.0408"}, {"href": "https://doi.org/10.1098/rstb.2017.0408"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Philosophical%20Transactions%20of%20the%20Royal%20Society%20B%3A%20Biological%20Sciences", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1098/rstb.2017.0408", "name": "item", "description": "10.1098/rstb.2017.0408", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1098/rstb.2017.0408"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2018-10-08T00:00:00Z"}}, {"id": "10.1111/j.1365-2486.2006.01240.x", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-21T16:17:40Z", "type": "Journal Article", "created": "2006-09-26", "title": "Interactions between plant growth and soil nutrient cycling under elevated CO2: a meta-analysis", "description": "Abstract<p>free air carbon dioxide enrichment (FACE) and open top chamber (OTC) studies are valuable tools for evaluating the impact of elevated atmospheric CO2 on nutrient cycling in terrestrial ecosystems. Using meta\uffe2\uff80\uff90analytic techniques, we summarized the results of 117 studies on plant biomass production, soil organic matter dynamics and biological N2 fixation in FACE and OTC experiments. The objective of the analysis was to determine whether elevated CO2 alters nutrient cycling between plants and soil and if so, what the implications are for soil carbon (C) sequestration. Elevated CO2 stimulated gross N immobilization by 22%, whereas gross and net N mineralization rates remained unaffected. In addition, the soil C\uffe2\uff80\uff83:\uffe2\uff80\uff83N ratio and microbial N contents increased under elevated CO2 by 3.8% and 5.8%, respectively. Microbial C contents and soil respiration increased by 7.1% and 17.7%, respectively. Despite the stimulation of microbial activity, soil C input still caused soil C contents to increase by 1.2%\uffe2\uff80\uff83yr\uffe2\uff88\uff921. Namely, elevated CO2 stimulated overall above\uffe2\uff80\uff90 and belowground plant biomass by 21.5% and 28.3%, respectively, thereby outweighing the increase in CO2 respiration. In addition, when comparing experiments under both low and high N availability, soil C contents (+2.2%\uffe2\uff80\uff83yr\uffe2\uff88\uff921) and above\uffe2\uff80\uff90 and belowground plant growth (+20.1% and+33.7%) only increased under elevated CO2 in experiments receiving the high N treatments. Under low N availability, above\uffe2\uff80\uff90 and belowground plant growth increased by only 8.8% and 14.6%, and soil C contents did not increase. Nitrogen fixation was stimulated by elevated CO2 only when additional nutrients were supplied. These results suggest that the main driver of soil C sequestration is soil C input through plant growth, which is strongly controlled by nutrient availability. In unfertilized ecosystems, microbial N immobilization enhances acclimation of plant growth to elevated CO2 in the long\uffe2\uff80\uff90term. Therefore, increased soil C input and soil C sequestration under elevated CO2 can only be sustained in the long\uffe2\uff80\uff90term when additional nutrients are supplied.</p>", "keywords": ["2. Zero hunger", "enrichment", "microbial biomass", "atmospheric carbon-dioxide", "nitrogen-fixation", "dynamics", "04 agricultural and veterinary sciences", "15. Life on land", "6. Clean water", "forest", "tallgrass prairie", "13. Climate action", "responses", "0401 agriculture", " forestry", " and fisheries", "organic-matter", "respiration"]}, "links": [{"href": "https://doi.org/10.1111/j.1365-2486.2006.01240.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.1365-2486.2006.01240.x", "name": "item", "description": "10.1111/j.1365-2486.2006.01240.x", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/j.1365-2486.2006.01240.x"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2006-09-26T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=atmospheric+carbon-dioxide&f=json", "hreflang": "en-US"}, {"rel": "alternate", "type": "text/html", "title": "This document as HTML", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=atmospheric+carbon-dioxide&f=html", "hreflang": "en-US"}, {"rel": "collection", "type": "application/json", "title": "Collection URL", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main", "hreflang": "en-US"}, {"type": "application/geo+json", "rel": "first", "title": "items (first)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=atmospheric+carbon-dioxide&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=atmospheric+carbon-dioxide&offset=5", "hreflang": "en-US"}], "numberMatched": 5, "numberReturned": 5, "distributedFeatures": [], "timeStamp": "2026-09-22T01:48:05.625033Z"}