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.
2026
Sammendrag
Biochar, a carbon‐rich product of pyrolysis, is increasingly considered for soil amendment and climate change mitigation due to its potential to enhance soil properties and sequester carbon. However, its effects on tree growth in forest ecosystems remain uncertain. This study investigated the impact of biochar and nitrogen‐enriched biochar on the growth of two middle‐aged (approximately 60‐year‐old) Scots pine stands in southeastern Norway. Both stands were characterized by medium site indices and podzolic soils. In replicated field experiments, we applied four treatments consisting of an unfertilized control, and addition of biochar (2.5 t ha −1 ), nitrogen fertilizer (150 kg N ha −1 ), or biochar loaded with nitrogen (2.5 t biochar +150 kg N ha −1 ). The biochar was produced by pyrolysis of Norway spruce wood chips at 600°C. After 5 years, only treatments containing added nitrogen (either as mineral fertilizer or as nutrient‐enriched biochar) significantly increased basal area and volume growth compared to control. No significant difference in timing or magnitude of effects was observed between the nitrogen and biochar + nitrogen treatments, except better annual growth in the combined treatment the third year after fertilization, indicating rapid nitrogen release and uptake regardless of carrier. Pure biochar did not stimulate tree growth. While biochar did not negatively affect growth, its direct role as a growth stimulant was not supported under these conditions, at least in the short‐term with the dose of 2.5 t ha −1 . Further research is needed across different forest ages, site types, and application rates to fully understand biochar's potential in forestry.
Sammendrag
There is an increasing interest in using forests as a natural solution for enhancing terrestrial carbon dioxide removal, as part of climate smart forestry strategy to have a significant role in climate mitigation efforts. Harvest deferral is seen as one carbon farming practice to increase carbon sequestration in forests. The aim of this study was to evaluate the role of harvest deferral on carbon forest sink potential of Norwegian forests in the short, medium and long-term. Here, we carried out scenario analysis for the whole Norway during the 21st century to assess the effect on carbon sequestration of delaying harvest in a certain number of forests. The scenarios represented different levels of harvest deferral through Norwegian forests. Delaying harvest would increase CO2 removals in the medium (2050) and long-term (2100), resulting in an additional uptake of approximately 6 and 34 Tg CO2, respectively, when extending rotation for 20 years in those plots with high growth increment in the last 5 years. Scenarios where harvest was delayed for a longer period showed slightly higher CO2 removals by the end of the century. While harvest deferral scenarios showed positive effects in terms of climate change mitigation potential, there are several other aspects that need to be considered, such as trade-offs and synergies with other sustainability goals, leakage, market behaviour and willingness of forest owners to get involved in these carbon farming practices.
Forfattere
Sally A. Power Manjunatha H. Chandregowda Kirk Barnett Juan Pineiro Shun Hasegawa Coline Deveautour Eleanor Gibson‐Forty Jeff Chieppa Scott N. Johnson Sarah Facey Raul Ochoa‐HuesoSammendrag
Warming‐driven intensification of the hydrological cycle is altering global rainfall patterns. However, the relative importance of changes in the amount versus timing of rainfall and the role of atmospheric drivers of moisture demand in modifying relationships between rainfall, biodiversity and ecosystem functioning are currently unresolved. To address this, we undertook a 10‐year rainfall manipulation experiment in a mesic grassland in New South Wales, Australia. We used rain shelters to achieve five rainfall treatments: (i) ambient, (ii) ambient +50% (IA), (iii) ambient −50% (RA), (iv) reduced frequency (RF, cumulative ambient rainfall applied once every 3 weeks) and (v) summer drought (SD, no rain during the Austral summer). We found that inter‐annual variation in ANPP was best explained by the amount of growing season rainfall relative to potential evapotranspiration (i.e., P/PET, or aridity) (R 2 adj 0.52). Reductions in the amount of rainfall, particularly during summer, were associated with productivity decline, shifts in community composition and a loss of diversity. However, reducing the frequency of rain events had no overall effect on productivity, despite a loss of species diversity. Notably, treatment‐related declines in diversity and/or richness were associated with both increases (IA) and decreases (SD) in temporal stability of ANPP and the stabilising role of species asynchrony, thereby highlighting the importance of species identity and associated functional traits for community stability. Our study uniquely emphasises the importance of accounting for seasonal drivers of moisture demand when predicting functional responses to changes in rainfall regimes and highlights how the ecological mechanisms underpinning community stability are influenced by changes in both the amount and timing of rainfall. These mechanistic insights can enhance the predictive capacity of Earth system models and inform targeted management strategies to offset the negative effects of future, more extreme rainfall on the ecosystem services provided by global grasslands.
Forfattere
Bin Wang He Lyu Xueqian Zhang Mingkai Jiang Belinda E. Medlyn David Wårlind Jürgen Knauer Katrin Fleischer Daniel S. Goll Stefan Olin Xiaojuan Yang Lin Yu Sönke Zaehle Haicheng Zhang Kristian Schufft Kristine Y. Crous Yolima Carrillo Catriona A. Macdonald Ian C. Anderson Matthias M. Boer Mark Farrell Andrew Gherlenda Laura Castañeda-Gómez Shun Hasegawa Klaus Jarosch Paul Milham Raúl Ochoa-Hueso Varsha Pathare Johanna Pihlblad Juan Piñeiro Sally A. Power Peter B. Reich Markus Riegler David S. Ellsworth Benjamin SmithSammendrag
The capacity of nutrient-limited forests to enhance carbon (C) sequestration under elevated CO 2 (eCO 2 ) remains a critical uncertainty in C cycle modeling. While existing evidence suggests that low phosphorus (P) bioavailability may constrain CO 2 fertilization effects on plant growth, the extent to which this limitation modulates ecosystem responses to eCO 2 in forests adapted to P-deficient soils remains poorly understood. Here, using eight P-enabled models, we simulated the magnitudes and mechanisms through which P bioavailability interacts with eCO 2 , emulating an ecosystem-scale P enrichment experiment at a P-limited Eucalyptus forest undergoing long-term Free-Air CO 2 Enrichment. While models predicted pronounced P effects on tree growth, P enrichment unexpectedly did not increase the CO 2 effects on tree growth and ecosystem C sequestration. Models prioritized either CO 2 -driven or P-driven growth, but rarely both. This tradeoff emerged due to model-specific assumptions on 1) partitioning of the extra P in soil labile versus nonlabile pools; 2) plant photosynthetic acclimation to P deficiency; 3) C and nutrient use strategies regulating plant size and allocation; and 4) microbial-driven soil decomposition processes. By generating divergent yet biologically plausible outcomes, these predictions establish critical testable hypotheses for empirical research and highlight multiple P-related pathways that may influence the future land C sink.
Forfattere
Junbin Zhao Mounir Takriti Per-Erik Jansson Ed Jones Mikhail Mastepanov Erling Fjelldal Cornelya Klutsch David Kniha Runar Kjær Simon Weldon Kjetil Fadnes Knut Bjørkelo Jonathan Rizzi Christian Wilhelm Mohr Gunnhild Søgaard Jagadeesh YeluripatiSammendrag
Abstract Peatlands drained for agriculture and other uses release substantial carbon dioxide. Many countries estimate these emissions using the 2014 IPCC Tier 1 emission factors. Here we calibrated an ecosystem model with data from two cultivated peatland sites in Norway and simulate carbon dioxide emissions at 50 sites nationwide for 2001–2022. Model results showed that carbon dioxide emissions were strongly controlled by water table depth and aligned well with observations from other European peatlands of similar climate zones. Crucially, the Tier 1 emission factor matched our simulations only under very deep water tables (< –0.7 m), but overestimated emissions by 31–88% when water levels ranged from –0.7 m to –0.3 m. This indicates that Tier 1 methods may overstate emissions from cultivated peatlands in cool temperate and boreal regions, inflating estimates of mitigation potential. Tier 2 or 3 approaches can reduce uncertainty but require more field data.
Forfattere
Gunnhild SøgaardSammendrag
Det er ikke registrert sammendrag
Sammendrag
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Sammendrag
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Forfattere
Gunnhild SøgaardSammendrag
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Forfattere
Gunnhild SøgaardSammendrag
Det er ikke registrert sammendrag