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.
2018
Forfattere
Alan C. Gange Einar Heegaard Lynne Boddy Carrie Joy Andrew Paul M. Kirk Rune Halvorsen Thomas W. Kuyper Claus Bässler Jefferey M. Diez Jacob Heilman-Clausen Klaus Høiland Ulf Büntgen Håvard KauserudSammendrag
Despite the dramatic phenological responses of fungal fruiting to recent climate warming, it is unknown whether spatial distributions of fungi have changed and to what extent such changes are influenced by fungal traits, such as ectomycorrhizal (ECM) or saprotrophic lifestyles, spore characteristics, or fruit body size. Our overall aim was to understand how climate and fungal traits determine whether and how species‐specific fungal fruit body abundances have shifted across latitudes over time, using the UK national database of fruiting records. The data employed were recorded over 45 yr (1970–2014), and include 853 278 records of Agaricales, Boletales and Russulales, though we focus only on the most common species (with more than 3000 records each). The georeferenced observations were analysed by a Bayesian inference as a Gaussian additive model with a specification following a joint species distribution model. We used an offset, random contributions and fixed effects to isolate different potential biases from the trait‐specific interactions with latitude/climate and time. Our main aim was assessed by examination of the three‐way‐interaction of trait, predictor (latitude or climate) and time. The results show a strong trait‐specific shift in latitudinal abundance through time, as ECM species have become more abundant relative to saprotrophic species in the north. Along precipitation gradients, phenology was important, in that species with shorter fruiting seasons have declined markedly in abundance in oceanic regions, whereas species with longer seasons have become relatively more common overall. These changes in fruit body distributions are correlated with temperature and rainfall, which act directly on both saprotrophic and ECM fungi, and also indirectly on ECM fungi, through altered photosynthate allocation from their hosts. If these distributional changes reflect fungal activity, there will be important consequences for the responses of forest ecosystems to changing climate, through effects on primary production and nutrient cycling.
Forfattere
Yanliang Wang Erik Lysøe Tegan Armarego-Marriott Alexander Erban Lisa Paruch Andre van Eerde Ralph Bock Jihong Liu ClarkeSammendrag
Det er ikke registrert sammendrag
Forfattere
Hege UlfengSammendrag
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Forfattere
Eva Narten HøbergSammendrag
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Forfattere
Inger Sundheim FløistadSammendrag
Det er ikke registrert sammendrag
Sammendrag
Holdbarhet og bruk av tre Det finnes flere prinsipper for trebeskyttelse, slik som utnyttelse av trevirkets naturlige holdbarhet, konstruktiv trebeskyttelse, bruk av impregnerte trematerialer, bruk av modifiserte trematerialer og overflatebehandling.
Forfattere
Arne SteffenremSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
In the Nordic-Baltic region, there has been a growing concern about an increasing occurrence of multiple tops in young stands of Norway spruce. There is however a lack of documentation on the amount of such damages, and the causal agents involved. In two separate studies in SE Norway, we assessed the frequency of multiple tops in young sapling-sized stands, and studied the relationship between the occurrence of multiple tops and lammas growth the previous growing season on the sample trees. Study 1 included 44 planted and 10 naturally regenerated stands, while Study 2 included 68 planted stands with information on seed source. Among sample trees with multiple tops, 57% (Study 1) and 32% (Study 2) had signs of lammas growth the previous autumn, either in the form of an extended leading shoot or swollen bud. Site index as well as sample tree height were positively correlated to the occurrence of both lammas growth and multiple tops in both studies. In Study 1 we show that the probability of lammas growth was significantly higher in planted than in naturally regenerated stands. In Study 2 we show that it was higher in stands planted with seedlings grown from stand-origin seeds compared with improved seed material. Furthermore, the results of both studies show that lammas growth occurs most frequently among the dominant trees in the stand.
Sammendrag
Unmanned aerial vehicles (UAVs) are increasingly used as tools to perform a detailed assessment of post-harvest sites. One of the potential use of UAV photogrammetric data is to obtain tree-stump information that can then be used to support more precise decisions. This study developed and tested a methodology to automatically detect, segment, classify, and measure tree-stumps. Among the potential applications for single stump data, this study assessed the possibility (1) to detect and map root- and butt-rot on the stumps using a machine learning approach, and (2) directly measure or model tree stump diameter from the UAV data. The results revealed that the tree-stumps were detected with an overall accuracy of 68–80%, and once the stump was detected, the presence of root- and butt-rot was detected with an accuracy of 82.1%. Furthermore, the root mean square error of the UAV-derived measurements or model predictions for the stump diameter was 7.5 cm and 6.4 cm, respectively, and with the former systematically under predicting the diameter by 3.3 cm. The results of this study are promising and can lead to the development of more cost-effective and comprehensive UAV post-harvest surveys.