GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
Document type
Keywords
Publisher
Years
  • 1
    Electronic Resource
    Electronic Resource
    Sensitivity of C Sequestration in Reintroduced Sphagnum to Water-Level Variation in a Cutaway Peatland (2004)
    Oxford, UK; Malden, USA : Blackwell Science Inc
    Restoration ecology 12 (2004), S. 0 
    Details
    ISSN: 1526-100X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: The reintroduction of Sphagnum fragments has been found to be a promising method for restoring mire vegetation in a cutaway peatland. Although it is known that moisture controls Sphagnum photosynthesis, information concerning the sensitivity of carbon dynamics on water-level variation is still scarce. In a 4-year field experiment, we studied the carbon dynamics of reintroduced Sphagnum angustifolium material in a restored (rewetted) cutaway peatland. Cutaway peatland restored by Sphagnum reintroduction showed high sensitivity to variation in water level. Water level controlled both photosynthesis and respiration. Gross photosynthesis (PG) had a unimodal response to water-level variation with optimum level at −12 cm. The range of water level for high PG (above 60% of the maximum light-saturated PG) was between 22 and 1 cm below soil surface. Water level had a dual effect on total respiration. When the water level was below soil surface, peat respiration increased rapidly along the lowering water level until the respiration rate started to slow down at approximately −30 cm. Contrary to peat respiration, the response of Sphagnum respiration to water-level variation resembled that of photosynthesis with an optimum at −12 cm. In optimal conditions, Sphagnum reintroduction turned the cutaway site from carbon source to a sink of 23 g C/m2 per season (mid-May to the end of September). In dry conditions, lowered photosynthesis together with the higher peat respiration led to a net loss of 56 g C/m2. Although the water level above the optimum amplitude restricted CO2 fixation, a decrease in peat respiration led to a positive CO2 balance of 9 g C/m2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1061-2971.2004.00280.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Methane dynamics of a restored cut-away peatland (2000)
    Oxford, UK : Blackwell Science Ltd
    Global change biology 6 (2000), S. 0 
    Details
    ISSN: 1365-2486
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Geography
    Notes: We measured a cut-away peatland's CH4 dynamics using the static chamber technique one year before and two years after restoration (rewetting). The CH4 emissions were related to variation in vegetation and abiotic factors using multiple linear regression. A statistical model for CH4 flux with cottongrass cover (Eriophorum vaginatum L.), soil temperature, water level, and effective temperature sum index as driving variables explained most (r2 = 0.81) of the temporal and spatial variability in the fluxes. In addition to the direct increasing effect of raised water level on CH4 emissions, rewetting also promoted an increase of cottongrass cover which consequently increased carbon flux (substrate availability) into the system. The seasonal CH4 dynamics in tussocks followed seasonal CO2 dynamics till mid August but in late autumn CH4 emissions increased while CO2 influxes decreased. The reconstructed seasonal CH4 exchange was clearly higher following the rewetting, although it was still lower than emissions from pristine mires in the same area. However, our simulation for closed cottongrass vegetation showed that CH4 emissions from restored peatlands may remain at a lower level for a longer period of time even after sites have become fully vegetated and colonized by mire plants.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2486.2000.00341.x
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Restored cut-away peatland as a sink for atmospheric CO2 (1999)
    Springer
    Oecologia 120 (1999), S. 563-574 
    Details
    ISSN: 1432-1939
    Keywords: Key words Cut-away peatland ; CO2 exchange ; Eriophorum vaginatum ; Restoration ; Water level
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In a field study, we examined the relationship between vegetation, abiotic factors and the CO2 exchange dynamics of a cut-away peatland 20 years after production had ended. The main objective was to determine the effect of rewetting on the CO2 exchange dynamics, measured separately in Eriophorum vaginatum tussocks and intertussocks (almost non-vegetated surfaces) using closed-chamber techniques, one growing season before and three growing seasons after the rewetting treatment. Rewetting lowered total respiration (R TOT) and increased gross photosynthesis (P G), which resulted in a higher incorporation of CO2 into the system. The seasonal CO2 balance for the almost continuously submerged section of the rewetted site became positive 2 years after rewetting (9.1 g CO2-C m−2), and it was still higher in the 3rd year (64.5 g CO2-C m−2), i.e. the system accumulated carbon. In the driest section of the rewetted site the seasonal balance increased strongly, but the balance was still negative during the 3 years following rewetting with losses from the system of 44.1, 26.1, 38.3 g CO2-C m−2 in 1995, 1996 and 1997 respectively. At the control site seasonal balance during 1995–1997 varied between ecosystem C losses of 41.8 and 95.3 in an area with high Eriophorum cover and between 52.1 and 109.9 g CO2-C m−2 with lower cover. Simulation of a cut-away peatland with dense Eriophorum vegetation (Eriophorum cover 70%) showed that if the water level (WT) is low, the seasonal CO2 balance of the ecosystem can reach the compensation point of no net C change (P G = R TOT) only if weather conditions are favourable, but with a high WT the seasonal CO2 balance would be positive even under varying weather conditions. It can be concluded that with dense Eriophorum vegetation a restored cut-away peatland acts as a functional mire and becomes a sink for atmospheric CO2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004420050891
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    facet.materialart.
    Unknown
    HIMMELI v1.0: Helsinki Model of Methane build-up and emission for peatlands (2017)
    Copernicus Publications (EGU)
    In:  Geoscientific Model Development, 10 (12). pp. 4665-4691.
    Details
    Publication Date: 2021-12-13
    Description: Wetlands are one of the most significant natural sources of methane (CH4) to the atmosphere. They emit CH4 because decomposition of soil organic matter in waterlogged anoxic conditions produces CH4, in addition to carbon dioxide (CO2). Production of CH4 and how much of it escapes to the atmosphere depend on a multitude of environmental drivers. Models simulating the processes leading to CH4 emissions are thus needed for upscaling observations to estimate present CH4 emissions and for producing scenarios of future atmospheric CH4 concentrations. Aiming at a CH4 model that can be added to models describing peatland carbon cycling, we composed a model called HIMMELI that describes CH4 build-up in and emissions from peatland soils. It is not a full peatland carbon cycle model but it requires the rate of anoxic soil respiration as input. Driven by soil temperature, leaf area index (LAI) of aerenchymatous peatland vegetation, and water table depth (WTD), it simulates the concentrations and transport of CH4, CO2, and oxygen (O2) in a layered one-dimensional peat column. Here, we present the HIMMELI model structure and results of tests on the model sensitivity to the input data and to the description of the peat column (peat depth and layer thickness), and demonstrate that HIMMELI outputs realistic fluxes by comparing modeled and measured fluxes at two peatland sites. As HIMMELI describes only the CH4-related processes, not the full carbon cycle, our analysis revealed mechanisms and dependencies that may remain hidden when testing CH4 models connected to complete peatland carbon models, which is usually the case. Our results indicated that (1) the model is flexible and robust and thus suitable for different environments; (2) the simulated CH4 emissions largely depend on the prescribed rate of anoxic respiration; (3) the sensitivity of the total CH4 emission to other input variables is mainly mediated via the concentrations of dissolved gases, in particular, the O2 concentrations that affect the CH4 production and oxidation rates; (4) with given input respiration, the peat column description does not significantly affect the simulated CH4 emissions in this model version.
    Type: Article , PeerReviewed
    Format: text
    Format: archive
    DOI: 10.5194/gmd-10-4665-2017
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    OceanRep: Article in a Scientific Journal - peer-reviewed
  • 5
    facet.materialart.
    Unknown
    Impact of spatial microclimatic variability on carbon and nitrogen cycling leading to methane emissions during the non-growing season of Siikaneva, Finland (2021)
    EGU
    In:  EPIC3EGU General Assembly 2021, online, 2021-04-19-2021-04-30EGU
    Details
    Publication Date: 2021-07-01
    Description: Non-growing season greenhouse gas emissions are still underrepresented in observation systems as well as process-based models despite growing evidence of their importance to annual budgets in high latitude regions. We therefore investigate ecological and biogeochemical processes in global carbon and nitrogen cycles during the non-growing and shoulder seasons at Siikaneva, nearby Hyytiälä Research Station in boreal Finland. The FluxWIN project investigates the current underestimation of annual methane (CH4) emissions from boreal ecosystems by combining high-frequency greenhouse gas measurements and biogeochemical monitoring. Identifying the processes leading to the large observed CH4 emissions requires thorough analysis of potential meteorological drivers controlling the soil temperature, including radiative forcing, surface energy balance and snow pack characteristics. The location of our research site within extensive long-term scientific infrastructure allows us to compare the measurements obtained from our newly set up meteorological station at a well-drained upland forest site to the ones recorded about 1 km south-east at an ICOS station in open fen. While both stations are subject to the same large-scale meteorological forcing due to their spatial proximity, the different ecosystem types might produce very different microclimates with differing freeze-thaw and soil temperature dynamics, which has potential implications for local carbon and nitrogen cycling leading to CH4 exchange. Controlling for spatial microclimatic variability will help us to evaluate the representativeness of our flux measurements and identified soil, geophysical and biogeochemical drivers when expanded to a larger spatial scale.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 6
    facet.materialart.
    Unknown
    Inter-seasonal investigation of coupled C & N greenhouse gas fluxes in pristine northern ecosystems (2021)
    EGU General Assembly
    In:  EPIC3EGU General Assembly 2021, online, 2021-04-19-2021-04-30online, EGU General Assembly
    Details
    Publication Date: 2021-06-11
    Description: Accurate annual greenhouse gas (GHG) budgets are the crucial baseline for global climate change forecast scenarios. On the other hand, the parameterization of these forecast models requires more than high-quality GHG datasets, but also the constant improvement of the representation of GHG producing and consuming processes. Extensive research efforts are therefore focusing on increasing our knowledge of the main GHG producing carbon (C) and nitrogen (N) cycles, though surprisingly not so much into their direct interaction. Most annual GHG budgets from pristine northern ecosystems are based on interpolated datasets from sampling campaigns mainly taken during the growing season. Within the ERC funded FluxWIN project, we are investigating how soil and pore water C & N interact and their biogeochemical GHG drivers change over seasons. Freeze-thaw events have previously been identified as significant GHG drivers by rapidly changing moisture and oxygen conditions in the soil matrix, but it remains unclear if and how C & N coupling contributes to these non-growing season emissions. Therefore, a fully automated static chamber system is monitoring GHG fluxes in high frequency at a boreal peatland ecosystem in Siikaneva, Finland. Nutrient stocks and biogeochemical dynamics within the soil matrix are compared to GHG soil-atmosphere exchange in the form of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) all year-round. We control for climatic variability and isolate differences in non-growing season emissions by using a moisture gradient from well-drained upland soils to adjacent wetland ecosystems. The use of these automated high-frequency GHG measurements in combination with year-round biogeochemical monitoring maximizes the likelihood of capturing episodic emissions and their drivers, which are particularly important during fall freeze and spring thaw periods. The gained information on the coupled C & N biogeochemical cycles will improve feedback estimates of climate change by including non-growing season processes in global-scale process-based models.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 7
    facet.materialart.
    Unknown
    FluxWIN – The role of non-growing season processes in the methane and nitrous oxide budgets in pristine northern ecosystems (2020)
    AGU
    In:  EPIC3AGU 2020 Fall Meeting, online, 2020-12-01-2020-12-17AGU.org, AGU
    Details
    Publication Date: 2021-06-11
    Description: The importance of non-growing season greenhouse gas fluxes to annual budgets in pristine northern terrestrial ecosystems is growing in awareness. Greenhouse gas (GHG) fluxes during the non-growing season and freeze-thaw dynamics are still underrepresented and may be a reason why current process-based models predict inadequate annual methane (CH4) and nitrous oxide (N2O) budgets. FluxWIN is therefore investigating ecological and biogeochemical processes in global carbon (C) and nitrogen (N) cycles during the non-growing and shoulder seasons by combining high-frequency greenhouse gas measurements, biogeochemical monitoring and process-based modeling. Siikaneva, nearby Hyytiälä Research Station in boreal Finland, is an ICOS-certified site and well situated within long-term scientific infrastructure to compare and combine high-frequency greenhouse gas measurement techniques and investigate freeze-thaw dynamics. An automated static chamber technique is used with inline laser gas analysis to obtain soil-atmosphere CH4 and N2O exchange in real time. Additional automated sampling of diffusion tubing will sample soil gas concentrations in the same analytical system. We control for climatic variability and isolate differences in non-growing season emissions by using a moisture gradient from well-drained upland soils to adjacent wetland ecosystems. The use of these automated high-frequency GHG measurements in combination with year-round biogeochemical monitoring maximizes the likelihood of capturing episodic emissions and their drivers, which are particularly important during fall freeze and spring thaw periods. The gained information on ecosystem function and biogeochemical cycles for temperate, boreal, and arctic regions will improve feedback estimates to climate change by including non-growing season processes in global-scale process-based models.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
    Format: application/pdf
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 8
    facet.materialart.
    Unknown
    FluxWIN – The role of non-growing season processes in the methane and nitrous oxide budgets in pristine northern ecosystems (2022)
    ICOS
    In:  EPIC3ICOS Science Conference 2022, Utrecht, Netherlands & online, 2022-09-13-2022-09-15online, ICOS
    Details
    Publication Date: 2022-10-28
    Description: The importance of non-growing season greenhouse gas fluxes to annual budgets in pristine northern terrestrial ecosystems is growing in awareness. Greenhouse gas (GHG) fluxes during the non-growing season and freeze-thaw dynamics are still underrepresented and may be a reason why current process-based models underestimate annual methane (CH4) and nitrous oxide (N2O) budgets. The FluxWIN project investigates ecological and biogeochemical processes in global carbon (C) and nitrogen (N) cycles during the non-growing and shoulder seasons by combining high-frequency greenhouse gas measurements, biogeochemical monitoring and process-based modeling. A new automated chamber system was established in 2021 to obtain soil-atmosphere CO2, CH4 and N2O exchange in real time. Additional soil gases and biogeochemical and physical parameters are monitored year-round. We control for climatic variability and quantify differences in non-growing season emissions across the landscape by using a moisture gradient from well-drained upland soils to adjacent wetland ecosystems. The use of these automated high-frequency GHG measurements in combination with biogeochemical monitoring maximizes the likelihood of capturing episodic emissions and their drivers, which are hypothesized to be particularly important during fall freeze and spring thaw periods. The gained information on cold season biogeochemical cycles will improve feedback estimates to climate change by including non-growing season processes in global-scale process-based models.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , NonPeerReviewed
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 9
    facet.materialart.
    Unknown
    The ABCflux database: Arctic–boreal CO〈sub>2〈/sub> flux observations and ancillary information aggregated to monthly time steps across terrestrial ecosystems (2022)
    In:  EPIC3Earth System Science Data, 14(1), pp. 179-208, ISSN: 1866-3516
    Details
    Publication Date: 2024-04-22
    Description: Past efforts to synthesize and quantify the magnitude and change in carbon dioxide (CO2) fluxes in terrestrial ecosystems across the rapidly warming Arctic–boreal zone (ABZ) have provided valuable information but were limited in their geographical and temporal coverage. Furthermore, these efforts have been based on data aggregated over varying time periods, often with only minimal site ancillary data, thus limiting their potential to be used in large-scale carbon budget assessments. To bridge these gaps, we developed a standardized monthly database of Arctic–boreal CO2 fluxes (ABCflux) that aggregates in situ measurements of terrestrial net ecosystem CO2 exchange and its derived partitioned component fluxes: gross primary productivity and ecosystem respiration. The data span from 1989 to 2020 with over 70 supporting variables that describe key site conditions (e.g., vegetation and disturbance type), micrometeorological and environmental measurements (e.g., air and soil temperatures), and flux measurement techniques. Here, we describe these variables, the spatial and temporal distribution of observations, the main strengths and limitations of the database, and the potential research opportunities it enables. In total, ABCflux includes 244 sites and 6309 monthly observations; 136 sites and 2217 monthly observations represent tundra, and 108 sites and 4092 observations represent the boreal biome. The database includes fluxes estimated with chamber (19 % of the monthly observations), snow diffusion (3 %) and eddy covariance (78 %) techniques. The largest number of observations were collected during the climatological summer (June–August; 32 %), and fewer observations were available for autumn (September–October; 25 %), winter (December–February; 18 %), and spring (March–May; 25 %). ABCflux can be used in a wide array of empirical, remote sensing and modeling studies to improve understanding of the regional and temporal variability in CO2 fluxes and to better estimate the terrestrial ABZ CO2 budget. ABCflux is openly and freely available online (Virkkala et al., 2021b, https://doi.org/10.3334/ORNLDAAC/1934).
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 10
    facet.materialart.
    Unknown
    Trait measurements of Sphagnum moss from northern peatlands (2021)
    PANGAEA
    Details
    Publication Date: 2023-03-14
    Keywords: B1; B2; B3; B4; B5; B6; B7; B8; bog; Capitulum, dry weight; Capitulum, water content; Capitulum, width; Capitulum density; Carbon; Carbon/Nitrogen ratio; Elemental analyzer CHNS-O (EA1110); Elevation of event; Event label; Fascicle density; fen; functional plant trait; HL_HRS; HL_IS; HL_KAL; HL_KLA; HL_KS; HL_LA; HL_TE; Latitude of event; Longitude of event; Mire; mire succession; Moisture index; Nitrogen; Northern_peatlands_B1; Northern_peatlands_B2; Northern_peatlands_B3; Northern_peatlands_B4; Northern_peatlands_B5; Northern_peatlands_B6; Northern_peatlands_B7; Northern_peatlands_B8; Northern_peatlands_HL_HRS; Northern_peatlands_HL_IS; Northern_peatlands_HL_KAL; Northern_peatlands_HL_KLA; Northern_peatlands_HL_KS; Northern_peatlands_HL_LA; Northern_peatlands_HL_TE; Northern_peatlands_S1; Northern_peatlands_S13; Northern_peatlands_S2; Northern_peatlands_S3; Northern_peatlands_S31; Northern_peatlands_S33; Northern_peatlands_S4; Northern_peatlands_S41; Northern_peatlands_S42; Northern_peatlands_S5; Northern_peatlands_S51; Northern_peatlands_S53; Northern_peatlands_S6; Northern_peatlands_u10; Northern_peatlands_u13; Northern_peatlands_u14; Northern_peatlands_u16; Northern_peatlands_u18; Northern_peatlands_u2; Northern_peatlands_u24; Northern_peatlands_u26; Northern_peatlands_u29; Northern_peatlands_u33; Northern_peatlands_u43; Northern_peatlands_u52; Northern_peatlands_u62; Northern_peatlands_u65; Northern_peatlands_u70; Optional event label; Peatland; Peat thickness; pH; S1; S13; S2; S3; S31; S33; S4; S41; S42; S5; S51; S53; S6; Species; u10; u13; u14; u16; u18; u2; u24; u26; u29; u33; u43; u52; u62; u65; u70
    Type: Dataset
    Format: text/tab-separated-values, 4199 data points
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    DATA PANGAEA
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...