Change search
Refine search result
1 - 3 of 3
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Olid, Carolina
    et al.
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Klaminder, Jonatan
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Monteux, Sylvain
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Johansson, Margareta
    Dorrepaal, Ellen
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Decade of experimental permafrost thaw reduces turnover of young carbon and increases losses of old carbon, without affecting the net carbon balance2020In: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 26, no 10, p. 5886-5898Article in journal (Refereed)
    Abstract [en]

    Thicker snowpacks and their insulation effects cause winter-warming and invoke thaw of permafrost ecosystems. Temperature-dependent decomposition of previously frozen carbon (C) is currently considered one of the strongest feedbacks between the Arctic and the climate system, but the direction and magnitude of the net C balance remains uncertain. This is because winter effects are rarely integrated with C fluxes during the snow-free season and because predicting the net C balance from both surface processes and thawing deep layers remains challenging. In this study, we quantified changes in the long-term net C balance (net ecosystem production) in a subarctic peat plateau subjected to 10 years of experimental winter-warming. By combining(210)Pb and(14)Cdating of peat cores with peat growth models, we investigated thawing effects on year-round primary production and C losses through respiration and leaching from both shallow and deep peat layers. Winter-warming and permafrost thaw had no effect on the net C balance, but strongly affected gross C fluxes. Carbon losses through decomposition from the upper peat were reduced as thawing of permafrost induced surface subsidence and subsequent waterlogging. However, primary production was also reduced likely due to a strong decline in bryophytes cover while losses from the old C pool almost tripled, caused by the deepened active layer. Our findings highlight the need to estimate long-term responses of whole-year production and decomposition processes to thawing, both in shallow and deep soil layers, as they may contrast and lead to unexpected net effects on permafrost C storage.

    Download full text (pdf)
    FULLTEXT01
  • 2.
    Olid, Carolina
    et al.
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Rodellas, Valentí
    Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra, Spain.
    Rocher-Ros, Gerard
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Garcia-Orellana, Jordi
    Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra, Spain; Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain.
    Diego-Feliu, Marc
    Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra, Spain; Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain; Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya, Barcelona, Spain; Associated Unit: Hydrogeology Group, UPC-CSIC, Barcelona, Spain.
    Alorda-Kleinglass, Aaron
    Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra, Spain.
    Bastviken, David
    Department of Thematic Studies—Environmental Change, Linköping University, Linköping, Sweden.
    Karlsson, Jan
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Groundwater discharge as a driver of methane emissions from Arctic lakes2022In: Nature Communications, E-ISSN 2041-1723, Vol. 13, no 1, article id 3667Article in journal (Refereed)
    Abstract [en]

    Lateral CH4 inputs to Arctic lakes through groundwater discharge could be substantial and constitute an important pathway that links CH4 production in thawing permafrost to atmospheric emissions via lakes. Yet, groundwater CH4 inputs and associated drivers are hitherto poorly constrained because their dynamics and spatial variability are largely unknown. Here, we unravel the important role and drivers of groundwater discharge for CH4 emissions from Arctic lakes. Spatial patterns across lakes suggest groundwater inflows are primarily related to lake depth and wetland cover. Groundwater CH4 inputs to lakes are higher in summer than in autumn and are influenced by hydrological (groundwater recharge) and biological drivers (CH4 production). This information on the spatial and temporal patterns on groundwater discharge at high northern latitudes is critical for predicting lake CH4 emissions in the warming Arctic, as rising temperatures, increasing precipitation, and permafrost thawing may further exacerbate groundwater CH4 inputs to lakes.

  • 3.
    Zahajská, Petra
    et al.
    Department of Geology, Lund University, Lund, Sweden; Institute of Geology and Palaeontology, Faculty of Science, Charles University, Prague, Czech Republic.
    Olid, Carolina
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Stadmark, Johanna
    Department of Geology, Lund University, Lund, Sweden.
    Fritz, Sherilyn C.
    Department of Earth and Atmospheric Sciences, School of Biological Sciences, University of Nebraska-Lincoln, NE, Lincoln, United States.
    Opfergelt, Sophie
    Earth and Life Institute, Université Catholique de Louvain, Louvain-la-Neuve, Belgium.
    Conley, Daniel J.
    Department of Geology, Lund University, Lund, Sweden.
    Modern silicon dynamics of a small high-latitude subarctic lake2021In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 18, no 7, p. 2325-2345Article in journal (Refereed)
    Abstract [en]

    High biogenic silica (BSi) concentrations occur sporadically in lake sediments throughout the world; however, the processes leading to high BSi concentrations vary. We explored the factors responsible for the high BSi concentration in sediments of a small, high-latitude subarctic lake (Lake 850). The Si budget of this lake had not been fully characterized before to establish the drivers of BSi accumulation in this environment. To do this, we combined measurements of variations in stream discharge, dissolved silica (DSi) concentrations, and stable Si isotopes in both lake and stream water with measurements of BSi content in lake sediments. Water, radon, and Si mass balances revealed the importance of groundwater discharge as a main source of DSi to the lake, with groundwater-derived DSi inputs 3 times higher than those from ephemeral stream inlets. After including all external DSi sources (i.e., inlets and groundwater discharge) and estimating the total BSi accumulation in the sediment, we show that diatom production consumes up to 79 % of total DSi input. Additionally, low sediment accumulation rates were observed based on the dated gravity core. Our findings thus demonstrate that groundwater discharge and low mass accumulation rate can account for the high BSi accumulation during the last 150 cal yr BP. Globally, lakes have been estimated to retain one-fifth of the annual DSi terrestrial weathering flux that would otherwise be delivered to the ocean. Well-constrained lake mass balances, such as presented here, bring clarity to those estimates of the terrestrial Si cycle sinks.

1 - 3 of 3
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf