{"type": "FeatureCollection", "features": [{"id": "10.1007/s00248-003-9001-x", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:34Z", "type": "Journal Article", "created": "2004-06-15", "title": "Microbial Community Structure And Oxidative Enzyme Activity In Nitrogen-Amended North Temperate Forest Soils", "description": "Large regions of temperate forest are subject to elevated atmospheric nitrogen (N) deposition which can affect soil organic matter dynamics by altering mass loss rates, soil respiration, and dissolved organic matter production. At present there is no general model that links these responses to changes in the organization and operation of microbial decomposer communities. Toward that end, we studied the response of litter and soil microbial communities to high levels of N amendment (30 and 80 kg ha(-1) yr(-1)) in three types of northern temperate forest: sugar maple/basswood (SMBW), sugar maple/red oak (SMRO), and white oak/black oak (WOBO). We measured the activity of extracellular enzymes (EEA) involved directly in the oxidation of lignin and humus (phenol oxidase, peroxidase), and indirectly, through the production of hydrogen peroxide (glucose oxidase, glyoxal oxidase). Community composition was analyzed by extracting and quantifying phospholipid fatty acids (PLFA) from soils. Litter EEA responses at SMBW sites diverged from those at oak-bearing sites (SMRO, BOWO), but the changes were not statistically significant. For soil, EEA responses were consistent across forests types: phenol oxidase and peroxidase activities declined as a function of N dose (33-73% and 5-41%, respectively, depending on forest type); glucose oxidase and glyoxal oxidase activities increased (200-400% and 150-300%, respectively, depending on forest type). Principal component analysis (PCA) ordinated forest types and treatment responses along two axes; factor 1 (44% of variance) was associated with phenol oxidase and peroxidase activities, factor 2 (31%) with glucose oxidase. Microbial biomass did not respond to N treatment, but nine of the 23 PLFA that formed >1 mol% of total biomass showed statistically significant treatment responses. PCA ordinated forest types and treatment responses along three axes (36%, 26%, 12% of variance). EEA factors 1 and 2 correlated negatively with PLFA factor 1 ( r = -0.20 and -0.35, respectively, n = 108) and positively with PLFA factor 3 ( r = +0.36 and +0.20, respectively, n = 108). In general, EEA responses were more strongly tied to changes in bacterial PLFA than to changes in fungal PLFA. Collectively, our data suggests that N inhibition of oxidative activity involves more than the repression of ligninase expression by white-rot basidiomycetes.", "keywords": ["Michigan", "Nitrogen", "Science", "Ecology and Evolutionary Biology", "Nature Conservation", "Microbiology", "Trees", "Soil", "Geoecology/Natural Processes", "Health Sciences", "Cellular and Developmental Biology", "Ecosystem", "Phospholipids", "Soil Microbiology", "2. Zero hunger", "Analysis of Variance", "Principal Component Analysis", "Ecology", "Life Sciences", "Natural Resources and Environment", "Molecular", "04 agricultural and veterinary sciences", "15. Life on land", "Enzymes", "13. Climate action", "0401 agriculture", " forestry", " and fisheries"]}, "links": [{"href": "https://doi.org/10.1007/s00248-003-9001-x"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Microbial%20Ecology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1007/s00248-003-9001-x", "name": "item", "description": "10.1007/s00248-003-9001-x", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s00248-003-9001-x"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2004-04-19T00:00:00Z"}}, {"id": "10.1007/pl00008870", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:33Z", "type": "Journal Article", "created": "2006-04-10", "title": "Spring Ephemeral Herbs And Nitrogen Cycling In A Northern Hardwood Forest: An Experimental Test Of The Vernal Dam Hypothesis", "description": "In the late 1970s R.N. Muller and F.H. Bormann posited their 'vernal dam' hypothesis, stating that spring-ephemeral herbs in deciduous forests serve as a temporary sink for N when overstory trees are dormant, and then release this N later, in the summer, when the trees are active. This hypothesis has gained wide acceptance, yet two of its critical assumptions have never been experimentally tested: (1) that N taken up by spring ephemerals would otherwise be lost from the ecosystem, and (2) that N from senesced ephemeral tissues contributes to increased rates of summertime N mineralization. To test these assumptions, I quantified patterns of N cycling and loss from a set of paired plots, half of which served as controls and from half of which all spring-ephemeral plants were removed. There were no significant differences in NO3- leaching between plots with and without spring ephemeral vegetation. These results are consistent with the relatively low rates of N uptake by the dominant spring ephemeral, Allium tricoccum, and its apparent preference for NH4+, which is far less mobile in soil than NO3-. In addition, based on sequential sampling, I found that soil microorganisms took up 8 times as much N during the spring than did spring-ephemeral herbs (microbial uptake=3.19 vs. plant uptake=0.41 g N m-2), suggesting that microbial immobilization of N is the dominant sink for N during this season. Removal of spring ephemeral vegetation also had no effect on summertime rates of net N mineralization. Furthermore, the addition of spring ephemeral litter to soil+forest floor microcosms did not significantly increase rates of N mineralization in a laboratory incubation. Instead, this experiment demonstrated the overwhelming influence of forest floor litter in controlling the release of mineral N from these soils. Overall, neither assumption of the vernal dam hypothesis holds true in this ecosystem, where patterns of N cycling and loss appear to be dominated by microbial decomposition of forest floor material and soil organic matter.", "keywords": ["0106 biological sciences", "NO3\u2013 Leaching", "N Immobilization", "Science", "Ecology and Evolutionary Biology", "Key Words Vernal Dam", "Natural Resources and Environment", "Molecular", "04 agricultural and veterinary sciences", "15. Life on land", "Spring Ephemerals", "01 natural sciences", "Microbial Biomass", "Legacy", "Health Sciences", "0401 agriculture", " forestry", " and fisheries", "Cellular and Developmental Biology"], "contacts": [{"organization": "Rothstein, David E.", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1007/pl00008870"}, {"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/pl00008870", "name": "item", "description": "10.1007/pl00008870", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/pl00008870"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2000-08-23T00:00:00Z"}}, {"id": "10.1007/pl00008869", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:33Z", "type": "Journal Article", "created": "2006-04-10", "title": "Combined Effects Of Atmospheric Co2 And N Availability On The Belowground Carbon And Nitrogen Dynamics Of Aspen Mesocosms", "description": "It is uncertain whether elevated atmospheric CO2 will increase C storage in terrestrial ecosystems without concomitant increases in plant access to N. Elevated CO2 may alter microbial activities that regulate soil N availability by changing the amount or composition of organic substrates produced by roots. Our objective was to determine the potential for elevated CO2 to change N availability in an experimental plant-soil system by affecting the acquisition of root-derived C by soil microbes. We grew Populus tremuloides (trembling aspen) cuttings for 2 years under two levels of atmospheric CO2 (36.7 and 71.5 Pa) and at two levels of soil N (210 and 970 \u00b5g N g-1). Ambient and twice-ambient CO2 concentrations were applied using open-top chambers, and soil N availability was manipulated by mixing soils differing in organic N content. From June to October of the second growing season, we measured midday rates of soil respiration. In August, we pulse-labeled plants with 14CO2 and measured soil 14CO2 respiration and the 14C contents of plants, soils, and microorganisms after a 6-day chase period. In conjunction with the August radio-labeling and again in October, we used 15N pool dilution techniques to measure in situ rates of gross N mineralization, N immobilization by microbes, and plant N uptake. At both levels of soil N availability, elevated CO2 significantly increased whole-plant and root biomass, and marginally increased whole-plant N capital. Significant increases in soil respiration were closely linked to increases in root biomass under elevated CO2. CO2 enrichment had no significant effect on the allometric distribution of biomass or 14C among plant components, total 14C allocation belowground, or cumulative (6-day) 14CO2 soil respiration. Elevated CO2 significantly increased microbial 14C contents, indicating greater availability of microbial substrates derived from roots. The near doubling of microbial 14C contents at elevated CO2 was a relatively small quantitative change in the belowground C cycle of our experimental system, but represents an ecologically significant effect on the dynamics of microbial growth. Rates of plant N uptake during both 6-day periods in August and October were significantly greater at elevated CO2, and were closely related to fine-root biomass. Gross N mineralization was not affected by elevated CO2. Despite significantly greater rates of N immobilization under elevated CO2, standing pools of microbial N were not affected by elevated CO2, suggesting that N was cycling through microbes more rapidly. Our results contained elements of both positive and negative feedback hypotheses, and may be most relevant to young, aggrading ecosystems, where soil resources are not yet fully exploited by plant roots. If the turnover of microbial N increases, higher rates of N immobilization may not decrease N availability to plants under elevated CO2.", "keywords": ["0106 biological sciences", "root-: biomass-", "Ecology and Evolutionary Biology", "nitrogen-fixation", "Environmental-Sciences)", "01 natural sciences", "nitrogen", "biomass-", "nitrogen-cycle", "nitrogen-", "Microorganisms-", "carbon-14", "124-38-9: CARBON DIOXIDE", "C Cycle", "Spermatophytes-", "Spermatophyta-", "Key Words Atmospheric CO2", "Cellular and Developmental Biology", "Populus Tremuloides Michx", "2. Zero hunger", "carbon-dioxide: atmospheric-", "plant-nutrition", "Climatology- (Environmental-Sciences)", "Angiosperms-", "Angiospermae-", "Plants-", "Natural Resources and Environment", "04 agricultural and veterinary sciences", "global-climate-change", "microbe- (Microorganisms-)", "7727-37-9: NITROGEN", "chemical-composition", "carbon-sequestration", "mineral-uptake", "soil-biology", "Science", "Vascular-Plants", "poplars-", "respiration-", "carbon-dioxide-enrichment", "carbon-dioxide", "Populus-tremuloides [trembling-aspen] (Salicaceae-)", "carbon-cycle", "Health Sciences", "Salicaceae-: Dicotyledones-", "soil-respiration", "content", "Plantae-", "14762-75-5: CARBON-14", "mineralization-", "Molecular", "forest-soils", "15. Life on land", "Rhizodeposition", "soil-flora", "N Cycle", "13. Climate action", "cuttings-", "roots-", "Legacy", "Terrestrial-Ecology (Ecology-", "0401 agriculture", " forestry", " and fisheries", "Dicots-", "ecosystems-"], "contacts": [{"organization": "Mikan, Carl J., Zak, Donald R., Kubiske, Mark E., Pregitzer, Kurt S.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1007/pl00008869"}, {"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/pl00008869", "name": "item", "description": "10.1007/pl00008869", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/pl00008869"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2000-08-23T00:00:00Z"}}, {"id": "10.1007/s00442-005-0191-4", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:43Z", "type": "Journal Article", "created": "2005-07-22", "title": "Fine Root Chemistry And Decomposition In Model Communities Of North-Temperate Tree Species Show Little Response To Elevated Atmospheric Co2 And Varying Soil Resource Availability", "description": "Rising atmospheric [CO2] has the potential to alter soil carbon (C) cycling by increasing the content of recalcitrant constituents in plant litter, thereby decreasing rates of decomposition. Because fine root turnover constitutes a large fraction of annual NPP, changes in fine root decomposition are especially important. These responses will likely be affected by soil resource availability and the life history characteristics of the dominant tree species. We evaluated the effects of elevated atmospheric [CO2] and soil resource availability on the production and chemistry, mycorrhizal colonization, and decomposition of fine roots in an early- and late-successional tree species that are economically and ecologically important in north temperate forests. Open-top chambers were used to expose young trembling aspen (Populus tremuloides) and sugar maple (Acer saccharum) trees to ambient (36 Pa) and elevated (56 Pa) atmospheric CO2. Soil resource availability was composed of two treatments that bracketed the range found in the Upper Lake States, USA. After 2.5 years of growth, sugar maple had greater fine root standing crop due to relatively greater allocation to fine roots (30% of total root biomass) relative to aspen (7% total root biomass). Relative to the low soil resources treatment, aspen fine root biomass increased 76% with increased soil resource availability, but only under elevated [CO2]. Sugar maple fine root biomass increased 26% with increased soil resource availability (relative to the low soil resources treatment), and showed little response to elevated [CO2]. Concentrations of N and soluble phenolics, and C/N ratio in roots were similar for the two species, but aspen had slightly higher lignin and lower condensed tannins contents compared to sugar maple. As predicted by source-sink models of carbon allocation, pooled constituents (C/N ratio, soluble phenolics) increased in response to increased relative carbon availability (elevated [CO2]/low soil resource availability), however, biosynthetically distinct compounds (lignin, starch, condensed tannins) did not always respond as predicted. We found that mycorrhizal colonization of fine roots was not strongly affected by atmospheric [CO2] or soil resource availability, as indicated by root ergosterol contents. Overall, absolute changes in root chemical composition in response to increases in C and soil resource availability were small and had no effect on soil fungal biomass or specific rates of fine root decomposition. We conclude that root contributions to soil carbon cycling will mainly be influenced by fine root production and turnover responses to rising atmospheric [CO2], rather than changes in substrate chemistry.", "keywords": ["0106 biological sciences", "Science", "Climate", "Ecology and Evolutionary Biology", "Plant Roots", "01 natural sciences", "Trees", "Sugar Maple", "Soil", "Ergosterol", "Health Sciences", "Carbon-based Secondary Compounds", "Biomass", "Cellular and Developmental Biology", "Ecosystem", "Soil Microbiology", "Atmosphere", "Fungi", "Natural Resources and Environment", "Molecular", "04 agricultural and veterinary sciences", "Carbon Dioxide", "15. Life on land", "Soil C Cycling", "13. Climate action", "0401 agriculture", " forestry", " and fisheries", "Trembling Aspen"]}, "links": [{"href": "https://doi.org/10.1007/s00442-005-0191-4"}, {"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/s00442-005-0191-4", "name": "item", "description": "10.1007/s00442-005-0191-4", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s00442-005-0191-4"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2005-07-23T00:00:00Z"}}, {"id": "10.1007/s00442-005-0249-3", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:43Z", "type": "Journal Article", "created": "2005-10-04", "title": "Fungal Community Composition And Metabolism Under Elevated Co2 And O-3", "description": "Atmospheric CO(2) and O(3) concentrations are increasing due to human activity and both trace gases have the potential to alter C cycling in forest ecosystems. Because soil microorganisms depend on plant litter as a source of energy for metabolism, changes in the amount or the biochemistry of plant litter produced under elevated CO(2) and O(3) could alter microbial community function and composition. Previously, we have observed that elevated CO(2) increased the microbial metabolism of cellulose and chitin, whereas elevated O(3) dampened this response. We hypothesized that this change in metabolism under CO(2) and O(3) enrichment would be accompanied by a concomitant change in fungal community composition. We tested our hypothesis at the free-air CO(2) and O(3) enrichment (FACE) experiment at Rhinelander, Wisconsin, in which Populus tremuloides, Betula papyrifera, and Acer saccharum were grown under factorial CO(2) and O(3) treatments. We employed extracellular enzyme analysis to assay microbial metabolism, phospholipid fatty acid (PLFA) analysis to determine changes in microbial community composition, and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) to analyze the fungal community composition. The activities of 1,4-beta-glucosidase (+37%) and 1,4,-beta-N-acetylglucosaminidase (+84%) were significantly increased under elevated CO(2), whereas 1,4-beta-glucosidase activity (-25%) was significantly suppressed by elevated O(3). There was no significant main effect of elevated CO(2) or O(3) on fungal relative abundance, as measured by PLFA. We identified 39 fungal taxonomic units from soil using DGGE, and found that O(3) enrichment significantly altered fungal community composition. We conclude that fungal metabolism is altered under elevated CO(2) and O(3), and that there was a concomitant change in fungal community composition under elevated O(3). Thus, changes in plant inputs to soil under elevated CO(2) and O(3) can propagate through the microbial food web to alter the cycling of C in soil.", "keywords": ["0106 biological sciences", "Food Chain", "Extracellular Enzymes", "Science", "Ecology and Evolutionary Biology", "Polymerase Chain Reaction\u2013Denaturing Gradient Gel Electrophoresis", "Polymerase Chain Reaction", "01 natural sciences", "Soil Microbial Community", "Soil", "Ozone", "Health Sciences", "Acetylglucosaminidase", "Cellular and Developmental Biology", "Ecosystem", "Soil Microbiology", "beta-Glucosidase", "Fatty Acids", "Fungi", "Natural Resources and Environment", "Molecular", "04 agricultural and veterinary sciences", "Carbon Dioxide", "15. Life on land", "Fungal Metabolism", "Carbon", "Free-air CO 2 and O 3 Enrichment", "13. Climate action", "0401 agriculture", " forestry", " and fisheries", "Extracellular Space"]}, "links": [{"href": "https://doi.org/10.1007/s00442-005-0249-3"}, {"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/s00442-005-0249-3", "name": "item", "description": "10.1007/s00442-005-0249-3", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s00442-005-0249-3"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2005-10-05T00:00:00Z"}}, {"id": "10.1007/s00442-006-0381-8", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:43Z", "type": "Journal Article", "created": "2006-02-17", "description": "The aspen free-air CO2 and O3 enrichment (FACTS II-FACE) study in Rhinelander, Wisconsin, USA, is designed to understand the mechanisms by which young northern deciduous forest ecosystems respond to elevated atmospheric carbon dioxide (CO2) and elevated tropospheric ozone (O3) in a replicated, factorial, field experiment. Soil respiration is the second largest flux of carbon (C) in these ecosystems, and the objective of this study was to understand how soil respiration responded to the experimental treatments as these fast-growing stands of pure aspen and birch + aspen approached maximum leaf area. Rates of soil respiration were typically lowest in the elevated O3 treatment. Elevated CO2 significantly stimulated soil respiration (8-26%) compared to the control treatment in both community types over all three growing seasons. In years 6-7 of the experiment, the greatest rates of soil respiration occurred in the interaction treatment (CO2 + O3), and rates of soil respiration were 15-25% greater in this treatment than in the elevated CO2 treatment, depending on year and community type. Two of the treatments, elevated CO2 and elevated CO2 + O3, were fumigated with 13C-depleted CO2, and in these two treatments we used standard isotope mixing models to understand the proportions of new and old C in soil respiration. During the peak of the growing season, C fixed since the initiation of the experiment in 1998 (new C) accounted for 60-80% of total soil respiration. The isotope measurements independently confirmed that more new C was respired from the interaction treatment compared to the elevated CO2 treatment. A period of low soil moisture late in the 2003 growing season resulted in soil respiration with an isotopic signature 4-6 per thousand enriched in 13C compared to sample dates when the percentage soil moisture was higher. In 2004, an extended period of low soil moisture during August and early September, punctuated by a significant rainfall event, resulted in soil respiration that was temporarily 4-6 per thousand more depleted in 13C. Up to 50% of the Earth's forests will see elevated concentrations of both CO2 and O3 in the coming decades and these interacting atmospheric trace gases stimulated soil respiration in this study.", "keywords": ["0106 biological sciences", "Science", "Ecology and Evolutionary Biology", "Cell Respiration", "Acer", "Carbon Cycling", "Plant Roots", "01 natural sciences", "Trees", "Soil", "Ozone", "Stable Isotope", "Air Pollution", "Health Sciences", "\u03b4 13 C", "Global Change", "Cellular and Developmental Biology", "Betula", "Ecosystem", "Soil Microbiology", "Carbon Isotopes", "Atmosphere", "Natural Resources and Environment", "Molecular", "Carbon Dioxide", "15. Life on land", "Populus", "13. Climate action"]}, "links": [{"href": "https://doi.org/10.1007/s00442-006-0381-8"}, {"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/s00442-006-0381-8", "name": "item", "description": "10.1007/s00442-006-0381-8", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s00442-006-0381-8"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2006-02-18T00:00:00Z"}}, {"id": "10.1007/s004420050375", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:45Z", "type": "Journal Article", "created": "2002-08-25", "title": "Response Of Soil Biota To Elevated Atmospheric Co 2 In Poplar Model Systems", "description": "We tested the hypotheses that increased belowground allocation of carbon by hybrid poplar saplings grown under elevated atmospheric CO2 would increase mass or turnover of soil biota in bulk but not in rhizosphere soil. Hybrid poplar saplings (Populus\u00d7euramericana cv. Eugenei) were grown for 5 months in open-bottom root boxes at the University of Michigan Biological Station in northern, lower Michigan. The experimental design was a randomized-block design with factorial combinations of high or low soil N and ambient (34 Pa) or elevated (69 Pa) CO2 in five blocks. Rhizosphere microbial biomass carbon was 1.7 times greater in high-than in low-N soil, and did not respond to elevated CO2. The density of protozoa did not respond to soil N but increased marginally (P\u2009<\u20090.06) under elevated CO2. Only in high-N soil did arbuscular mycorrhizal fungi and microarthropods respond to CO2. In high-N soil, arbuscular mycorrhizal root mass was twice as great, and extramatrical hyphae were 11% longer in elevated than in ambient CO2 treatments. Microarthropod density and activity were determined in situ using minirhizotrons. Microarthropod density did not change in response to elevated CO2, but in high-N soil, microarthropods were more strongly associated with fine roots under elevated than ambient treatments. Overall, in contrast to the hypotheses, the strongest response to elevated atmospheric CO2 was in the rhizosphere where (1) unchanged microbial biomass and greater numbers of protozoa (P\u2009<\u20090.06) suggested faster bacterial turnover, (2) arbuscular mycorrhizal root length increased, and (3) the number of microarthropods observed on fine roots rose.", "keywords": ["0106 biological sciences", "2. Zero hunger", "Arbuscular Mycorrhizas", "Microarthropods", "Science", "Ecology and Evolutionary Biology", "Natural Resources and Environment", "Molecular", "04 agricultural and veterinary sciences", "15. Life on land", "Roots", "01 natural sciences", "Microbial Biomass", "Legacy", "Health Sciences", "0401 agriculture", " forestry", " and fisheries", "Key Words Atmospheric CO2", "Cellular and Developmental Biology"], "contacts": [{"organization": "Treonis, Amy, Lussenhop, John, Teeri, James A., Curtis, Peter S., Vogel, Christoph S.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1007/s004420050375"}, {"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/s004420050375", "name": "item", "description": "10.1007/s004420050375", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s004420050375"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "1998-01-09T00:00:00Z"}}, {"id": "10.1007/s004420100656", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:45Z", "type": "Journal Article", "created": "2003-02-13", "title": "Fine-Root Biomass And Fluxes Of Soil Carbon In Young Stands Of Paper Birch And Trembling Aspen As Affected By Elevated Atmospheric Co2 And Tropospheric O3", "description": "Rising atmospheric CO2 may stimulate future forest productivity, possibly increasing carbon storage in terrestrial ecosystems, but how tropospheric ozone will modify this response is unknown. Because of the importance of fine roots to the belowground C cycle, we monitored fine-root biomass and associated C fluxes in regenerating stands of trembling aspen, and mixed stands of trembling aspen and paper birch at FACTS-II, the Aspen FACE project in Rhinelander, Wisconsin. Free-air CO2 enrichment (FACE) was used to elevate concentrations of CO2 (average enrichment concentration 535\u00a0\u00b5l l-1) and O3 (53\u00a0nl l-1) in developing forest stands in 1998 and 1999. Soil respiration, soil pCO2, and dissolved organic carbon in soil solution (DOC) were monitored biweekly. Soil respiration was measured with a portable infrared gas analyzer. Soil pCO2 and DOC samples were collected from soil gas wells and tension lysimeters, respectively, at depths of 15, 30, and 125\u00a0cm. Fine-root biomass averaged 263\u00a0g m-2 in control plots and increased 96% under elevated CO2. The increased root biomass was accompanied by a 39% increase in soil respiration and a 27% increase in soil pCO2. Both soil respiration and pCO2 exhibited a strong seasonal signal, which was positively correlated with soil temperature. DOC concentrations in soil solution averaged ~12\u00a0mg l-1 in surface horizons, declined with depth, and were little affected by the treatments. A simplified belowground C budget for the site indicated that native soil organic matter still dominated the system, and that soil respiration was by far the largest flux. Ozone decreased the above responses to elevated CO2, but effects were rarely statistically significant. We conclude that regenerating stands of northern hardwoods have the potential for substantially greater C input to soil due to greater fine-root production under elevated CO2. Greater fine-root biomass will be accompanied by greater soil C efflux as soil respiration, but leaching losses of C will probably be unaffected.", "keywords": ["0106 biological sciences", "Ecology and Evolutionary Biology", "Aspen-FACE-project", "root-", "USA-", "pollutants-", "Environmental-Sciences)", "tropospheric-ozone", "forest-productivity", "01 natural sciences", "biomass-", "northern-forests", "124-38-9: CARBON DIOXIDE", "soil-carbon-flux", "terrestrial-ecosystems", "populus-tremuloides", "Cellular and Developmental Biology", "soil-carbon", "7440-44-0: CARBON", "carbon-", "fine-root", "Bioenergetics- (Biochemistry-and-Molecular-Biophysics)", "Natural Resources and Environment", "04 agricultural and veterinary sciences", "GLOBAL-ECOLOGY", "North-America", "Nearctic-region)", "Rhinelander- (Wisconsin-", "carbon-sequestration", "atmosphere-", "biomass-production", "dissolved-organic-carbon [DOC-]", "Science", "respiration-", "carbon-dioxide-enrichment", "forest-plantations", "carbon-dioxide", "carbon-storage", "fine-root-biomass", "belowground-biomass", "United-States-Wisconsin-Rhinelander", "carbon-cycle", "Health Sciences", "ozone-", "soil-respiration", "air-pollution", "global-change", "atmospheric-carbon-dioxide", "biomass", "Molecular", "15. Life on land", "ozone", "13. Climate action", "roots-", "Legacy", "Terrestrial-Ecology (Ecology-", "free-air-carbon-dioxide-enrichment [FREE-]: experimental-method", "0401 agriculture", " forestry", " and fisheries", "Northern Forests Global Change Carbon Sequestration Soil Respiration Dissolved Organic Carbon Soil PCO2"]}, "links": [{"href": "https://doi.org/10.1007/s004420100656"}, {"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/s004420100656", "name": "item", "description": "10.1007/s004420100656", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s004420100656"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2001-07-01T00:00:00Z"}}, {"id": "10.1007/s10533-004-7112-1", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:14:55Z", "type": "Journal Article", "created": "2005-11-04", "title": "Extracellular Enzyme Activities And Soil Organic Matter Dynamics For Northern Hardwood Forests Receiving Simulated Nitrogen Deposition", "description": "Anthropogenic nitrogen enrichment alters decomposition processes that control the flux of carbon (C) and nitrogen (N) from soil organic matter (SOM) pools. To link N-driven changes in SOM to microbial responses, we measured the potential activity of several extracellular enzymes involved in SOM degradation at nine experimental sites located in northern Michigan. Each site has three treatment plots (ambient, +30 and +80 kg N ha 1 y 1 ). Litter and soil samples were collected on five dates over the third growing season of N treatment. Phenol oxidase, peroxidase and cellobiohydrolase activities showed significant responses to N additions. In the Acer saccha- rum-Tilia americana ecosystem, oxidative activity was 38% higher in the litter horizon of high N treatment plots, relative to ambient plots, while oxidative activity in mineral soil showed little change. In the A. saccharum-Quercus rubra and Q. velutina-Q. alba ecosystems, oxidative activities declined in both litter (15 and 23%, respectively) and soil (29 and 38%, respectively) in response to high N treatment while cellobiohydrolase activity increased (6 and 39% for litter, 29 and 18% for soil, respectively). Over 3 years, SOM content in the high N plots has decreased in the Acer-Tilia ecosystem and increased in the two Quercus ecosystems, relative to ambient plots. For all three ecosystems, differences in SOM content in relation to N treatment were directly related (r 2 = 0.92) to an enzyme activity factor that included both oxidative and hydrolytic enzyme responses.", "keywords": ["Soil Science & Conservation", "Decomposition", "Science", "Ecology and Evolutionary Biology", "Terrestrial Pollution", "Natural Resources and Environment", "Molecular", "04 agricultural and veterinary sciences", "15. Life on land", "Biochemistry", "Phenol Oxidase", "Geochemistry", "Cellulase", "Soil Organic Matter", "Health Sciences", "0401 agriculture", " forestry", " and fisheries", "Nitrogen Deposition", "Cellular and Developmental Biology", "General", "Extracellular Enzyme Activity", "Geosciences"]}, "links": [{"href": "https://doi.org/10.1007/s10533-004-7112-1"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Biogeochemistry", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1007/s10533-004-7112-1", "name": "item", "description": "10.1007/s10533-004-7112-1", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1007/s10533-004-7112-1"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2005-08-01T00:00:00Z"}}, {"id": "10.1038/s41586-023-05791-5", "type": "Feature", "geometry": null, "properties": {"updated": "2026-04-04T16:18:00Z", "type": "Journal Article", "created": "2023-03-08", "title": "The giant diploid faba genome unlocks variation in a global protein crop", "description": "Abstract

Increasing the proportion of locally produced plant protein in currently meat-rich diets could substantially reduce greenhouse gas emissions and loss of biodiversity1. However, plant protein production is hampered by the lack of a cool-season legume equivalent to soybean in agronomic value2. Faba bean (Vicia fabaL.) has a high yield potential and is well suited for cultivation in temperate regions, but genomic resources are scarce. Here, we report a high-quality chromosome-scale assembly of the faba bean genome and show that it has expanded to a massive 13\uffe2\uff80\uff89Gb in size through an imbalance between the rates of amplification and elimination of retrotransposons and satellite repeats. Genes and recombination events are evenly dispersed across chromosomes and the gene space is remarkably compact considering the genome size, although with substantial copy number variation driven by tandem duplication. Demonstrating practical application of the genome sequence, we develop a targeted genotyping assay and use high-resolution genome-wide association analysis to dissect the genetic basis of seed size and hilum colour. The resources presented constitute a genomics-based breeding platform for faba bean, enabling breeders and geneticists to accelerate the\uffc2\uffa0improvement of sustainable protein production across the\uffc2\uffa0Mediterranean, subtropical and northern temperate agroecological zones. Increasing the proportion of locally produced plant protein in currently meat-rich diets could substantially reduce greenhouse gas emissions and loss of biodiversity 1 . However, plant protein production is hampered by the lack of a cool-season legume equivalent to soybean in agronomic value 2 . Faba bean ( Vicia faba L.) has a high yield potential and is well suited for cultivation in temperate regions, but genomic resources are scarce. Here, we report a high-quality chromosome-scale assembly of the faba bean genome and show that it has expanded to a massive 13\uffe2\uff80\uff89Gb in size through an imbalance between the rates of amplification and elimination of retrotransposons and satellite repeats. Genes and recombination events are evenly dispersed across chromosomes and the gene space is remarkably compact considering the genome size, although with substantial copy number variation driven by tandem duplication. Demonstrating practical application of the genome sequence, we develop a targeted genotyping assay and use high-resolution genome-wide association analysis to dissect the genetic basis of seed size and hilum colour. The resources presented constitute a genomics-based breeding platform for faba bean, enabling breeders and geneticists to accelerate the\uffc2\uffa0improvement of sustainable protein production across the\uffc2\uffa0Mediterranean, subtropical and northern temperate agroecological zones.