{
  "abstract": "Tree stems exchange greenhouse gases with the atmosphere but the magnitude, variability and drivers of these fluxes remain poorly understood. Here, we report stem fluxes of carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) in a boreal riparian forest , and investigate their spatiotemporal variability and ecosystem level importance. For two years, we measured CO 2 and CH 4 fluxes on a monthly basis in 14 spruces ( Picea abies ) and 14 birches ( Betula pendula ) growing near a headwater stream affected by historic ditching. We also measured N 2 O fluxes on three occasions. All tree stems were net emitters of CO 2 and CH 4 , while N 2 O fluxes were around zero. CO 2 fluxes correlated strongly with air temperature and peaked in summer. CH 4 fluxes correlated modestly with air temperature and solar radiation and peaked in late winter and summer. Trees with larger stem diameter emitted more CO 2 and less CH 4 and trees closer to the stream emitted more CO 2 and CH 4 . The CO 2 and CH 4 fluxes did not differ between spruce and birch, but correlations of CO 2 fluxes with stem diameter and distance to stream differed between the tree species. The absence of vertical trends in CO 2 and CH 4 fluxes along the stems and their low correlation with groundwater levels and soil CO 2 and CH 4 partial pressures suggest tree internal production as the primary source of stem emissions. At the ecosystem level, the stem CO 2 , CH 4 and N 2 O emissions represented 52 ± 16 % of the forest floor CO 2 emissions and 3 ± 1 % and 11 ± 40 % of the forest floor CH 4 and N 2 O uptake, respectively, during the snow-free period (median ± SE). The six month snow-cover period contributed 11 ± 45 % and 40 ± 29 % to annual stem CO 2 and CH 4 emissions, respectively. Overall, the stem gas fluxes were more typical for upland rather than wetland ecosystems likely due to historic ditching and subsequent groundwater level decrease.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "name": "Marcus Klaus"
    },
    {
      "name": "Mats Öquist"
    },
    {
      "name": "Kateřina Macháčová"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5e8d3xc72p6nk.bib",
  "cited_by": 5,
  "doi": "10.1016/j.scitotenv.2024.176243",
  "fulltext_url": null,
  "id": "5e8d3xc72p6nk",
  "issns": [
    "0048-9697",
    "1879-1026"
  ],
  "landing_url": "https://hal.science/hal-05767838v1",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.sde"
    ],
    [
      "openalex",
      "2306|Atmospheric and Environmental Gas Dynamics"
    ]
  ],
  "openalex": "W4402514512",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-28",
  "publisher": "Elsevier",
  "ris": "https://research.draconitic.com/paper/5e8d3xc72p6nk.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:42Z",
      "native_id": "hal-05767838",
      "source": "hal",
      "url": "https://hal.science/hal-05767838v1"
    }
  ],
  "subjects": [
    {
      "field": "earth",
      "origin": "hal:0.sde",
      "subfield": "environmental-science"
    }
  ],
  "title": "Tree stem-atmosphere greenhouse gas fluxes in a boreal riparian forest",
  "title_text": "Tree stem-atmosphere greenhouse gas fluxes in a boreal riparian forest",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:42Z",
  "url": "https://research.draconitic.com/paper/5e8d3xc72p6nk",
  "venue": "Science of the Total Environment",
  "versions": []
}