It has been hypothesized that greater production of total nonstructural carbohydrates (TNC) in foliage grown under elevated atmospheric carbon dioxide (CO2) will result in higher concentrations of defensive compounds in tree leaf litter, possibly leading to reduced rates of decomposition and nutrient cycling in forest ecosystems of the future. To evaluate the effects of elevated atmospheric CO2on litter chemistry and decomposition, we performed a 111 day laboratory incubation with leaf litter of trembling aspen (Populus tremuloidesMichaux) produced at 36\uffe2\uff80\uff83Pa and 56\uffe2\uff80\uff83Pa CO2and two levels of soil nitrogen (N) availability. Decomposition was quantified as microbially respired CO2and dissolved organic carbon (DOC) in soil solution, and concentrations of nonstructural carbohydrates, N, carbon (C), and condensed tannins were monitored throughout the incubation. Growth under elevated atmospheric CO2did not significantly affect initial litter concentrations of TNC, N, or condensed tannins. Rates of decomposition, measured as both microbially respired CO2and DOC did not differ between litter produced under ambient and elevated CO2. Total C lost from the samples was 38\uffe2\uff80\uff83mg\uffe2\uff80\uff83g\uffe2\uff88\uff921litter as respired CO2and 138\uffe2\uff80\uff83mg\uffe2\uff80\uff83g\uffe2\uff88\uff921litter as DOC, suggesting short\uffe2\uff80\uff90term pulses of dissolved C in soil solution are important components of the terrestrial C cycle. We conclude that litter chemistry and decomposition in trembling aspen are minimally affected by growth under higher concentrations of CO2.
", "keywords": ["Ecology and Evolutionary Biology", "carbohydrates", "Quaking aspen", "forest-soil", "litter-plant", "nitrogen", "nitrogen-", "Microlysimeter", "soil-chemistry", "cycling-", "populus-tremuloides", "Geology and Earth Sciences", "Soil Carbon", "Microbiology of soils", "Carbon cycle", "04 agricultural and veterinary sciences", "GLOBAL-ECOLOGY", "chemical-composition", "Organic-matter", "soil-solution", "nutrient-availability", "Tannin", "leaf-litter", "Science", "decomposition-", "Nutrient enrichment", "Carbohydrates", "carbohydrates-", "respiration-", "carbon-dioxide-enrichment", "Nitrogen in soil", "michigan-", "carbon sinks", "C", "Nutrient budget of forests", "Litter", "Populus tremuloides", "Global Change", "tannins-", "Decomposition", "forest-litter", "Foliage", "Carbon dioxide effects on forest litter", "Climatic changes", "15. Life on land", "carbon-nitrogen-ratio", "Forest litter decomposition", "N Ratio", "13. Climate action", "0401 agriculture", " forestry", " and fisheries", "microbial-activities", "nitrogen-content"]}, "links": [{"href": "https://doi.org/10.1046/j.1365-2486.2001.00388.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": "10.1046/j.1365-2486.2001.00388.x", "name": "item", "description": "10.1046/j.1365-2486.2001.00388.x", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1046/j.1365-2486.2001.00388.x"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2001-01-01T00:00:00Z"}}, {"id": "10.1093/treephys/22.7.435", "type": "Feature", "geometry": null, "properties": {"updated": "2026-07-25T16:18:28Z", "type": "Journal Article", "created": "2012-01-20", "title": "Responses Of Deciduous Broadleaf Trees To Defoliation In A Co2 Enriched Atmosphere", "description": "Relatively little is known about the implications of atmospheric CO2 enrichment for tree responses to biotic disturbances such as folivory. We examined the combined effects of elevated CO2 concentration ([CO2]) and defoliation on growth and physiology of sugar maple (Acer saccharum Marsh.) and trembling aspen (Populus tremuloides Michx.). Seedlings were planted in the ground in eight open-top chambers. Four chambers were ventilated with CO2-enriched air (ambient + 283 micromol mol-1) and four chambers were supplied with ambient air. After 6 weeks of growth, half of the leaf area was removed on a subset of seedlings of each species in each CO2 treatment. We monitored subsequent biomass gain and allocation, along with leaf gas exchange and chemistry. Defoliation did not significantly affect final seedling biomass in either species or CO2 treatment. Growth recovery following defoliation was associated with increased allocation to leaf mass in maple and a slight enhancement of mean photosynthesis in aspen. Elevated [CO2] did not significantly affect aspen growth, and the observed stimulation of maple growth was significant only in mid-season. Correspondingly, simulated responses of whole-tree photosynthesis to elevated [CO2] were constrained by a decrease in photosynthetic capacity in maple, and were partially offset by reductions in specific leaf area and biomass allocation to foliage in aspen. There was a significant interaction between [CO2] and defoliation on only a few of the measured traits. Thus, the data do not support the hypothesis that atmospheric CO2 enrichment will substantially alter tree responses to folivory. However, our findings do provide further indication that regeneration-stage growth rates of certain temperate tree species may respond only moderately to a near doubling of atmospheric [CO2].", "keywords": ["defoliation-", "0106 biological sciences", "Ecophysiology", "Quaking aspen", "biomass-allocation", "growth-response", "Growth", "Environmental-Sciences)", "01 natural sciences", "plant-composition", "Trees", "biomass-", "Spermatophyta-", "Biomass", "Photosynthesis", "plant-physiology", "defoliation", "Angiospermae-", "leaf-area", "GLOBAL-ECOLOGY", "seedling-growth", "source-sink-relations", "Populus-tremuloides", "gas-exchange", "Populus", "broadleaves-", "deciduous-tree", "forest-trees", "atmosphere-", "trees-", "biomass-production", "Acer saccharum", "Nitrogen", "Carbohydrates", "Acer", "carbon-dioxide-enrichment", "photosynthesis-", "growth-", "species-differences", "seedlings-", "wisconsin-", "Populus tremuloides", "photosynthesis", "Climatic changes", "Carbon Dioxide", "15. Life on land", "Plant Leaves", "leaves-", "Aceraceae-: Dicotyledones-", "Carbon dioxide", "Sugar maple", "Seedlings", "Terrestrial-Ecology (Ecology-", "Acer-saccharum"], "contacts": [{"organization": "Volin, John C., Kruger, Eric L., Lindroth, Richard L.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1093/treephys/22.7.435"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Tree%20Physiology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1093/treephys/22.7.435", "name": "item", "description": "10.1093/treephys/22.7.435", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1093/treephys/22.7.435"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2002-05-01T00:00:00Z"}}, {"id": "10.2307/2656979", "type": "Feature", "geometry": null, "properties": {"updated": "2026-07-25T16:20:35Z", "type": "Journal Article", "created": "2006-04-21", "title": "Genotypic Variation For Condensed Tannin Production In Trembling Aspen (Populs Tremuloides, Salicaceae) Under Elevated Co2 And In High- And Low-Fertility Soil", "description": "The carbon/nutrient balance hypothesis suggests that leaf carbon to nitrogen ratios influence the synthesis of secondary compounds such as condensed tannins. We studied the effects of rising atmospheric carbon dioxide on carbon to nitrogen ratios and tannin production. Six genotypes of Populus tremuloides were grown under elevated and ambient CO2 partial pressure and high\uffe2\uff80\uff90 and low\uffe2\uff80\uff90fertility soil in field open\uffe2\uff80\uff90top chambers in northern lower Michigan, USA. During the second year of exposure, leaves were harvested three times (June, August, and September) and analyzed for condensed tannin concentration. The carbon/nutrient balance hypothesis was supported overall, with significantly greater leaf tannin concentration at high CO2 and low soil fertility compared to ambient CO2 and high soil fertility. However, some genotypes increased tannin concentration at elevated compared to ambient CO2, while others showed no CO2 response. Performance of lepidopteran leaf miner (Phyllonorycter tremuloidiella) larvae feeding on these plants varied across genotypes, CO2, and fertility treatments. These results suggest that with rising atmospheric CO2, plant secondary compound production may vary within species. This could have consequences for plant\uffe2\uff80\uff93herbivore and plant\uffe2\uff80\uff93microbe interactions and for the evolutionary response of this species to global climate change.
", "keywords": ["0106 biological sciences", "Salicaceae", "genotype", "plant\u2013herbivore interaction", "Phyllonorycter-tremuloidiella", "Quaking aspen", "01 natural sciences", "plant-composition", "tannin", "nitrogen-", "carbon-dioxide: elevation-", "124-38-9: CARBON DIOXIDE", "Spermatophytes-", "Spermatophyta-", "genotypic-variation", "Population-Genetics (Population-Studies)", "2. Zero hunger", "carbon-", "Climatology- (Environmental-Sciences)", "Angiosperms-", "Angiospermae-", "Plants-", "GLOBAL-ECOLOGY", "Populus-tremuloides", "plant-pests", "climate-change", "genetic-variation", "forest-trees", "condensed tannins", "Nitrogen", "Science", "Vascular-Plants", "carbon-dioxide-enrichment", "Nutrition-", "genotypes-", "Phyllonorycter tremuloidiella", "Populus-tremuloides [trembling-aspen] (Salicaceae-)", "soil-fertility", "Populus tremuloides", "Salicaceae-: Dicotyledones-", "Biology", "Plantae-", "global change", "tannins-", "condensed-tannin: production-", "foliage-", "forest-pests", "Tannic acid", "Metabolism-", "Botany", "carbon dioxide", "forest-soils", "15. Life on land", "Carbon", "climate-", "Carbon dioxide", "13. Climate action", "Dicots-", "insect-pests"], "contacts": [{"organization": "Donald R. Zak, Jennifer L Mansfield, Kurt S. Pregitzer, Kurt S. Pregitzer, Peter S. Curtis, Peter S. Curtis,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.2307/2656979"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/American%20Journal%20of%20Botany", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.2307/2656979", "name": "item", "description": "10.2307/2656979", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.2307/2656979"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "1999-08-01T00:00:00Z"}}], "links": [{"rel": "self", "type": "application/geo+json", "title": "This document as GeoJSON", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Quaking+aspen&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=Quaking+aspen&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=Quaking+aspen&", "hreflang": "en-US"}, {"rel": "last", "type": "application/geo+json", "title": "items (last)", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items?keywords=Quaking+aspen&offset=3", "hreflang": "en-US"}], "numberMatched": 3, "numberReturned": 3, "distributedFeatures": [], "timeStamp": "2026-07-26T09:19:59.046342Z"}