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Publikasjoner

NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.

2019

Sammendrag

The Integrated Carbon Observation System (ICOS) research infrastructure is aimed at quantifying and understanding the greenhouse gas balance of Europe and neighboring regions. ICOS-Norway brings together the leading Norwegian institutes for greenhouse gas observations in the three Earth system domains atmosphere, ocean, and terrestrial ecosystems, providing world-leading competence, which is integrated into one jointly funded and operated infrastructure. This provides Norway with a state-of-the-art research infrastructure embedded in European and global efforts. Even though each Earth system domain was part of dedicated research infrastructures prior to the establishment of ICOS-Norway, the greenhouse gas community in Norway was divided and there was minimal collaboration across the Earth system domains. The overall goal of ICOS-Norway is to provide accurate and accessible data on, as well as integrated assessments of, the Norwegian carbon balance at regional scale, across the land, ocean, and atmosphere. ICOS-Norway has thus led to an increased impact of environmental observing systems in Norway and surrounding seas, easily seen through the number of publications and new proposals generated as collaborative efforts. This poster presents the ICOS-Norway infrastructure, including plans for expansion and long-term funding.

Sammendrag

The measurement network Integrated Carbon Observation System (ICOS) is dedicated to the quantification of fluxes of CO2, H2O, N2O and CH4 at the boundary between vegetation surfaces and the lower atmosphere. The implementation of observations sites follows strict protocols and a challenging labelling process to ensure standardized intercomparable observations. We report on our experiences in attempting to establish the only Norwegian ICOS Ecosystem site thus far, NO-Hur, located in an old-growth spruce forest at Hurdal in Southeast Norway. NOHur is planned as a class 2 site, with the option to an upgrade to class 1 later. The instrumentation and sensors needed, the requirements for spatial homogeneity and a detailed analysis of a digital terrain model are presented. The current status of the tower construction, the preliminary measurements obtained with the existing ICOScertified equipment at a test site, and the plans for integrating the measurements operationally into the network are shown

Til dokument

Sammendrag

Liming of acidic soils has been suggested as a strategy to enhance N2O reduction to N2 during heterotrophic denitrification, and mitigate N2O emission from N fertilised soils. However, the mechanisms involved and possible interactions of key soil parameters (NO3− and O2) still need to be clarified. To explore to what extent soil pH controls N2O emissions and the associated N2O/(N2O + N2) product ratio in an acidic sandy soil, we set-up three sequential incubation experiments using an unlimed control (pH 4.1) and a limed soil (pH 6.9) collected from a 50-year liming experiment. Interactions between different NO3− concentrations, N forms (ammonium- and nitrate) and oxygen levels (oxic and anoxic) on the liming effect of N2O emission and reduction were tested in these two sandy soils via direct N2 and N2O measurements. Our results showed 50-year liming caused a significant increase in denitrification and soil respiration rate of the acidic sandy soil. High concentrations of NO3− in soil (>10 mM N in soil solution, equivalent to 44.9 mg N kg−1 soil) almost completely inhibited N2O reduction to N2 (>90%) regardless of the soil pH value. With decreasing NO3− application rate, N2O reduction rate increased in both soils with the effect being more pronounced in the limed soil. Complete N2O reduction to N2 in the low pH sandy soil was also observed when soil NO3− concentration decreased below 0.2 mM NO3−. Furthermore, liming evidently increased both N2O emissions and the N2O/(N2+N2O) product ratio under oxic conditions when supplied with ammonium-based fertiliser, possibly due to the coupled impact of stimulated nitrification and denitrification. Overall, our data suggest that long-term liming has the potential to both increase and decrease N2O emissions, depending on the soil NO3− level, with high soil NO3− levels overriding the assumed direct pH effect on N2O/(N2+N2O) product ratio.