Boreal forests are ecosystems with low nitrogen (N) availability that store globally significant amounts of carbon (C), mainly in plant biomass and soil organic matter (SOM). Although crucial for future climate change predictions, the mechanisms controlling boreal C and N pools are not well understood. Here, using a three-year field experiment, we compare SOM decomposition and stabilization in the presence of roots, with exclusion of roots but presence of fungal hyphae and with exclusion of both roots and fungal hyphae. Roots accelerate SOM decomposition compared to the root exclusion treatments, but also promote a different soil N economy with higher concentrations of organic soil N compared to inorganic soil N accompanied with the build-up of stable SOM-N. In contrast, root exclusion leads to an inorganic soil N economy (i.e., high level of inorganic N) with reduced stable SOM-N build-up. Based on our findings, we provide a framework on how plant roots affect SOM decomposition and stabilization.
", "keywords": ["roots", "0106 biological sciences", "330", "Nitrogen", "Science", "ta1171", "Hyphae", "Models", " Biological", "Plant Roots", "01 natural sciences", "Article", "LITTER DECOMPOSITION", "Soil", "POLYPHENOLS", "CARBON SEQUESTRATION", "soil organic matter", "Taiga", "SDG 13 - Climate Action", "SUGAR MAPLE", "Biomass", "Organic Chemicals", "forest ecology", "106026 Ecosystem research", "Ecosystem", "Soil Microbiology", "TANNINS", "2. Zero hunger", "106022 Mikrobiologie", "ECTOMYCORRHIZAL FUNGI", "MYCORRHIZA", "Q", "ta1182", "Forestry", "04 agricultural and veterinary sciences", "Plants", "15. Life on land", "Carbon", "Environmental sciences", "NITROGEN", "Boreal forests", "106026 \u00d6kosystemforschung", "13. Climate action", "SDG 13 \u2013 Ma\u00dfnahmen zum Klimaschutz", "106022 Microbiology", "ta1181", "0401 agriculture", " forestry", " and fisheries", "COMMUNITIES", "STORAGE"]}, "links": [{"href": "https://www.nature.com/articles/s41467-019-11993-1.pdf"}, {"href": "https://doi.org/10.1038/s41467-019-11993-1"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Nature%20Communications", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1038/s41467-019-11993-1", "name": "item", "description": "10.1038/s41467-019-11993-1", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1038/s41467-019-11993-1"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2019-09-04T00:00:00Z"}}, {"id": "10.1093/treephys/17.8-9.577", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:17:16Z", "type": "Journal Article", "created": "2012-04-06", "title": "Root Mass, Net Primary Production And Turnover In Aspen, Jack Pine And Black Spruce Forests In Saskatchewan And Manitoba, Canada", "description": "Root biomass, net primary production and turnover were studied in aspen, jack pine and black spruce forests in two contrasting climates. The climate of the Southern Study Area (SSA) near Prince Albert, Saskatchewan is warmer and drier in the summer and milder in the winter than the Northern Study Area (NSA) near Thompson, Manitoba, Canada. Ingrowth soil cores and minirhizotrons were used to quantify fine root net primary production (NPPFR). Average daily fine root growth (m m(-2) day(-1)) was positively correlated with soil temperature at 10-cm depth (r(2) = 0.83-0.93) for all three species, with black spruce showing the strongest temperature effect. At both study areas, fine root biomass (measured from soil cores) and fine root length (measured from minirhizotrons) were less for jack pine than for the other two species. Except for the aspen stands, estimates of NPPFR from minirhizotrons were significantly greater than estimates from ingrowth cores. The core method underestimated NPPFR because it does not account for simultaneous fine root growth and mortality. Minirhizotron NPPFR estimates ranged from 59 g m(-2) year(-1) for aspen stands at SSA to 235 g m(-2) year(-1) for black spruce at NSA. The ratio of NPPFR to total detritus production (aboveground litterfall + NPPFR) was greater for evergreen forests than for deciduous forests, suggesting that carbon allocation patterns differ between boreal evergreen and deciduous forests. In all stands, NPPFR consistently exceeded annual fine root turnover and the differences were larger for stands in the NSA than for stands in the SSA, whereas the difference between study areas was only significant for black spruce. The imbalance between NPPFR and fine root turnover is sufficient to explain the net accumulation of carbon in boreal forest soils.", "keywords": ["carbon balance", "0106 biological sciences", "detritus production", "550", "fine roots", "04 agricultural and veterinary sciences", "15. Life on land", "BOREAS", "01 natural sciences", "root turnover", "0401 agriculture", " forestry", " and fisheries", "boreal forests", "soil carbon", "Forest Sciences"], "contacts": [{"organization": "Steele, Sarah J., Gower, Stith T., Vogel, Jason G., Norman, John M.,", "roles": ["creator"]}]}, "links": [{"href": "https://doi.org/10.1093/treephys/17.8-9.577"}, {"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/17.8-9.577", "name": "item", "description": "10.1093/treephys/17.8-9.577", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1093/treephys/17.8-9.577"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "1997-08-01T00:00:00Z"}}, {"id": "10.1111/1365-2745.13504", "type": "Feature", "geometry": null, "properties": {"updated": "2026-09-20T16:17:24Z", "type": "Journal Article", "created": "2020-09-25", "title": "Invasive earthworms reduce chemical defense and increase herbivory and pathogen infection in native trees", "description": "Abstract
Recent research shows that earthworms can alter defense traits of plants against herbivores and pathogens by affecting soil biochemistry. Yet, the effects of invasive earthworms on defense traits of native plants from previously earthworm\uffe2\uff80\uff90free ecosystems as well as the consequences for multitrophic interactions are virtually unknown.
Here we use a combination of an observational study and a complementary experimental study to investigate the effects of invasive earthworms on leaf defense traits, herbivore damage and pathogen infection in two poplar tree species (Populus balsamifera and Populus tremuloides) native to North American boreal forests.
Our observational study showed that earthworm invasion was associated with enhanced leaf herbivory (by leaf\uffe2\uff80\uff90chewing insects) in saplings of both tree species. However, we only detected significant shifts in the concentration of chemical defense compounds in response to earthworm invasion for P. balsamifera. Specifically, leaf phenolic concentrations, including salicinoids and catechin, were lower in P. balsamifera from earthworm\uffe2\uff80\uff90invaded sites.
Our experimental study confirmed an earthworm\uffe2\uff80\uff90induced reduction in leaf defense levels in P. balsamifera for one of the defense compounds, tremulacin. The experimental study additionally showed that invasive earthworms reduced leaf dry matter content, potentially increasing leaf palatability, and enhanced susceptibility of trees to infection by a fungal pathogen, but not to aphid infestation, in the same tree species.
Synthesis. Our results show that invasive earthworms can decrease the concentrations of some chemical defense compounds in P. balsamifera, which could make them susceptible to leaf\uffe2\uff80\uff90chewing insects. Such potential impacts of invasive earthworms are likely to have implications for tree survival and competition, native tree biodiversity and ecosystem functioning.
", "keywords": ["0106 biological sciences", "multi-trophic interactions", "secondary metabolites", "15. Life on land", "01 natural sciences", "invasion ecology", "plant\u2013herbivore interactions", "13. Climate action", "international", "physical defense", "570 Life sciences; biology", "boreal forests", "Plan_S-Compliant_TA", "Research Articles", "belowground invasion"]}, "links": [{"href": "https://boris.unibe.ch/152111/1/1365-2745.13504.pdf"}, {"href": "https://besjournals.onlinelibrary.wiley.com/doi/pdf/10.1111/1365-2745.13504"}, {"href": "https://doi.org/10.1111/1365-2745.13504"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/Journal%20of%20Ecology", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/1365-2745.13504", "name": "item", "description": "10.1111/1365-2745.13504", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/1365-2745.13504"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2020-10-09T00:00:00Z"}}, {"id": "10.1111/ejss.12264", "type": "Feature", "geometry": null, "properties": {"license": "Closed Access", "updated": "2026-09-20T16:17:27Z", "type": "Journal Article", "created": "2015-05-14", "title": "Changes In Forest Floor And Mineral Soil Carbon And\u00a0Nitrogen Stocks In A Boreal Forest After Clear-Cutting And\u00a0Mechanical Site Preparation", "description": "SummarySignificant amounts of organic carbon (C) and nitrogen (N) are accumulated in soil in boreal forests. However, increased concern has been shown regarding the negative impacts of forestry operations on both the C sequestration and N stocks in soil. Changes in the C and N stocks in woody debris, forest floor and mineral soil (0\uffe2\uff80\uff9320\uffe2\uff80\uff89cm) were studied in Eastern Finland for 10\uffe2\uff80\uff89years after stem\uffe2\uff80\uff90only clear\uffe2\uff80\uff90cutting followed by soil harrowing. Samples were taken from the uncut forest and from the different microsites formed by the harrowing (ridges, furrows and undisturbed areas). Carbon and N from logging residues were not incorporated into the forest floor or mineral soil stocks to any great extent. After 5\uffe2\uff80\uff89years the C stock above the mineral soil was smaller (<\uffe2\uff80\uff8920%) in the treated area than in the uncut forest and after 10\uffe2\uff80\uff89years it was <\uffe2\uff80\uff8950% smaller. The corresponding N stock was marginally larger (<\uffe2\uff80\uff895%) after 5\uffe2\uff80\uff89years, but smaller (<\uffe2\uff80\uff8920%) after 10\uffe2\uff80\uff89years. In the mineral soil there were no changes; only the furrows lost C and N when compared with the other microsites, but not when compared with the forest. Harrowing increased the spatial variation in the forest floor C and N stocks. The comparison of the N losses from the soil and logging residues and woody debris with the leaching losses, the amounts utilized by the regenerating vegetation or estimated to be immobilized by the stumps at the same site indicated that N which remained after the clear\uffe2\uff80\uff90cutting was retained at the site. For a full understanding of the impact of such a disturbance on stocks at a site all significant fluxes and stocks would need to be monitored.
", "keywords": ["0106 biological sciences", "maaper\u00e4", "havumets\u00e4t", "hakkuut\u00e4hteet", "hiili", "carbon", "04 agricultural and veterinary sciences", "15. Life on land", "ta4112", "01 natural sciences", "nitrogen", "soil", "felling", "typpi", "Muut aihealueet", "0401 agriculture", " forestry", " and fisheries", "boreal forests", "hakkuu"]}, "links": [{"href": "https://doi.org/10.1111/ejss.12264"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/European%20Journal%20of%20Soil%20Science", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/ejss.12264", "name": "item", "description": "10.1111/ejss.12264", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/ejss.12264"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2015-05-14T00:00:00Z"}}, {"id": "10.1111/nph.17365", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-09-20T16:17:46Z", "type": "Journal Article", "created": "2021-03-29", "title": "New insight to the role of microbes in the methane exchange in trees: evidence from metagenomic sequencing", "description": "SummaryMethane (CH4) exchange in tree stems and canopies and the processes involved are among the least understood components of the global CH4 cycle. Recent studies have focused on quantifying tree stems as sources of CH4 and understanding abiotic CH4 emissions in plant canopies, with the role of microbial in situ CH4 formation receiving less attention. Moreover, despite initial reports revealing CH4 consumption, studies have not adequately evaluated the potential of microbial CH4 oxidation within trees. In this paper, we discuss the current level of understanding on these processes. Further, we demonstrate the potential of novel metagenomic tools in revealing the involvement of microbes in the CH4 exchange of plants, and particularly in boreal trees. We detected CH4\uffe2\uff80\uff90producing methanogens and novel monooxygenases, potentially involved in CH4 consumption, in coniferous plants. In addition, our field flux measurements from Norway spruce (Picea abies) canopies demonstrate both net CH4 emissions and uptake, giving further evidence that both production and consumption are relevant to the net CH4 exchange. Our findings, together with the emerging diversity of novel CH4\uffe2\uff80\uff90producing microbial groups, strongly suggest microbial analyses should be integrated in the studies aiming to reveal the processes and drivers behind plant CH4 exchange.
", "keywords": ["0301 basic medicine", "330", "ta1172", "metaani", "bakteerit", "Trees", "03 medical and health sciences", "boreal forests", "Ymp\u00e4rist\u00f6tiede", "2. Zero hunger", "0303 health sciences", "Norway", "ta1183", "kasvifysiologia", "puut (kasvit)", "genomiikka", "15. Life on land", "ta4112", "methanogenic archaea", "mets\u00e4t", "plant microbiome", "tree", "methane exchange", "boreaalinen vy\u00f6hyke", "mikrobisto", "13. Climate action", "Environmental Science", "aineiden kierto", "Metagenomics", "methanotrophic bacteria", "arkeonit", "Methane", "captured metagenomics"]}, "links": [{"href": "https://nph.onlinelibrary.wiley.com/doi/pdf/10.1111/nph.17365"}, {"href": "https://doi.org/10.1111/nph.17365"}, {"rel": "related", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/New%20Phytologist", "name": "related record", "description": "related record", "type": "application/json"}, {"rel": "self", "type": "application/geo+json", "title": "10.1111/nph.17365", "name": "item", "description": "10.1111/nph.17365", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main/items/10.1111/nph.17365"}, {"rel": "collection", "type": "application/json", "title": "Collection", "name": "collection", "description": "Collection", "href": "https://repository.soilwise-he.eu/cat/collections/metadata:main"}], "time": {"date": "2021-05-02T00:00:00Z"}}, {"id": "10.1111/nph.18120", "type": "Feature", "geometry": null, "properties": {"license": "Open Access", "updated": "2026-09-20T16:17:47Z", "type": "Journal Article", "created": "2022-03-28", "title": "Solar radiation drives methane emissions from the shoots of Scots pine", "description": "Summary
Plants are recognized as sources of aerobically produced methane (CH4), but the seasonality, environmental drivers and significance of CH4 emissions from the canopies of evergreen boreal trees remain poorly understood.
We measured the CH4 fluxes from the shoots of Pinus sylvestris (Scots pine) and Picea abies (Norway spruce) saplings in a static, non\uffe2\uff80\uff90steady\uffe2\uff80\uff90state chamber setup to investigate if the shoots of boreal conifers are a source of CH4 during spring.
We found that the shoots of Scots pine emitted CH4 and these emissions correlated with the photosynthetically active radiation. For Norway spruce, the evidence for CH4 emissions from the shoots was inconclusive.
Our study shows that the canopies of evergreen boreal trees are a potential source of CH4 in the spring and that these emissions are driven by a temperature\uffe2\uff80\uff90by\uffe2\uff80\uff90light interaction effect of solar radiation either directly or indirectly through its effects on tree physiological processes.
Shoot\uffe2\uff80\uff90level emissions of aerobically produced methane (CH4) may be an overlooked source of tree\uffe2\uff80\uff90derived CH4, but insufficient understanding of the interactions between their environmental and physiological drivers still prevents the reliable upscaling of canopy CH4 fluxes.
We utilised a novel automated chamber system to continuously measure CH4 fluxes from the shoots of Pinus sylvestris (Scots pine) saplings under drought to investigate how canopy CH4 fluxes respond to the drought\uffe2\uff80\uff90induced alterations in their physiological processes and to isolate the shoot\uffe2\uff80\uff90level production of CH4 from soil\uffe2\uff80\uff90derived transport and photosynthesis.
We found that aerobic CH4 emissions are not affected by the drought\uffe2\uff80\uff90induced stress, changes in physiological processes, or decrease in photosynthesis. Instead, these emissions vary on short temporal scales with environmental drivers such as temperature, suggesting that they result from abiotic degradation of plant compounds.
Our study shows that aerobic CH4 emissions from foliage are distinct from photosynthesis\uffe2\uff80\uff90related processes. Thus, instead of photosynthesis rates, it is more reliable to construct regional and global estimates for the aerobic CH4 emission based on regional differences in foliage biomass and climate, also accounting for short\uffe2\uff80\uff90term variations of weather variables such as air temperature and solar radiation.
Shoot\uffe2\uff80\uff90level emissions of aerobically produced methane (CH4) may be an overlooked source of tree\uffe2\uff80\uff90derived CH4, but insufficient understanding of the interactions between their environmental and physiological drivers still prevents the reliable upscaling of canopy CH4 fluxes.
We utilised a novel automated chamber system to continuously measure CH4 fluxes from the shoots of Pinus sylvestris (Scots pine) saplings under drought to investigate how canopy CH4 fluxes respond to the drought\uffe2\uff80\uff90induced alterations in their physiological processes and to isolate the shoot\uffe2\uff80\uff90level production of CH4 from soil\uffe2\uff80\uff90derived transport and photosynthesis.
We found that aerobic CH4 emissions are not affected by the drought\uffe2\uff80\uff90induced stress, changes in physiological processes, or decrease in photosynthesis. Instead, these emissions vary on short temporal scales with environmental drivers such as temperature, suggesting that they result from abiotic degradation of plant compounds.
Our study shows that aerobic CH4 emissions from foliage are distinct from photosynthesis\uffe2\uff80\uff90related processes. Thus, instead of photosynthesis rates, it is more reliable to construct regional and global estimates for the aerobic CH4 emission based on regional differences in foliage biomass and climate, also accounting for short\uffe2\uff80\uff90term variations of weather variables such as air temperature and solar radiation.
Plants are recognized as sources of aerobically produced methane (CH4), but the seasonality, environmental drivers and significance of CH4 emissions from the canopies of evergreen boreal trees remain poorly understood.
We measured the CH4 fluxes from the shoots of Pinus sylvestris (Scots pine) and Picea abies (Norway spruce) saplings in a static, non\uffe2\uff80\uff90steady\uffe2\uff80\uff90state chamber setup to investigate if the shoots of boreal conifers are a source of CH4 during spring.
We found that the shoots of Scots pine emitted CH4 and these emissions correlated with the photosynthetically active radiation. For Norway spruce, the evidence for CH4 emissions from the shoots was inconclusive.
Our study shows that the canopies of evergreen boreal trees are a potential source of CH4 in the spring and that these emissions are driven by a temperature\uffe2\uff80\uff90by\uffe2\uff80\uff90light interaction effect of solar radiation either directly or indirectly through its effects on tree physiological processes.