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.
2025
Forfattere
Irena FundovaSammendrag
Det er ikke registrert sammendrag
Forfattere
Darius KviklysSammendrag
European fruit research institute network (EUFRIN) has started coordinated apple and pear rootstock trials across the Europe in 2017. First pear rootstock trial was established in 2019 where quince rootstocks from NIAB (UK) breeding program ‘QR196-9’ and ‘QR530-11’ were compared with rootstocks ‘Adams’ and ‘Sydo’. Investigations were conducted with pear cultivar ‘Conference’ in Spain, Romania, Poland and Norway during 2019-2023. In all sites the most vigorous pear trees grew on ‘QR196-9’ rootstock. On the average of four trial sites, the weakest growth was recorded on ‘QR530-11’, except the Spanish site. Pear trees on rootstock ‘Adams’ produced the highest cumulative yields. Cumulative yields on other rootstocks were significantly lower by 16-23% without significant differences between them. However, site geographical position, climate and soil properties had a significant effect on rootstock performance. Similar to trees on ‘Adams’ high pear yield in Spain was harvested from trees on ‘QR196-9’; on ‘QR530-11’ rootstock in Poland, but ‘Sydo’ and ‘QR530-11’ rootstocks gave the highest yield in Romania. On the average of all sites, the least cumulative fertility index was recorded on ‘QR196-9’. Significant rootstock site interactions were revealed: rootstock ‘Adams’ had the highest cumulative fertility index in Spain and Norway, while rootstock ‘QR530-11’ in Poland and Romania.
Sammendrag
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Forfattere
Aksel Granhus Ulrika Jansson Kjersti Holt Hanssen Jørund Rolstad Ignacio Sevillano Ken Olaf StoraunetSammendrag
Denne arbeidet bygger videre på et tidligere publisert arbeid (NIBIO Rapport 10/48, 2024), der vi ved hjelp av modellbaserte framskrivinger av prøveflatene i Landsskogtakseringen undersøkte effekten av økt andel lukket hogst på CO2 opptaket i norsk skog fram mot år 2100. En sentral forutsetning i prognosene var at årlig hogstkvantum i scenariene med økende andel lukket hogst skulle holdes på samme nivå som i referansescenariet («Business as usual», BAU), der omfanget av lukket hogst ble holdt uendret i forhold til nivået de siste årene. Resultatene viste at scenariet med høyest andel lukket hogst vil kunne øke det akkumulerte CO2-opptaket fram mot år 2100 med 31,8 Mt. Resultatene viste samtidig at dette vil kreve at det drives et aktivt skogbruk med hogst på et større areal for å kunne hogge samme kvantum som i BAU. I denne rapporten belyses nærmere hvilke typer skog som påvirkes av hogst i framskrivingene. Hogstarealet i prognosene fram mot 2100 er derfor fordelt på hogstform, skogtype (hovedtreslag), bonitetsklasser, vegetasjonstyper, klasser mht. driftsveilengde, aldersklasser, samt naturskog/ikke naturskog. Videre angis størrelsesorden av areal i yngre grandominert skog som kan være egnet for omstilling til selektiv hogst på sikt.
Sammendrag
Based on data from 58 stands located in three different regions within Norway, this study presents new models for quantifying growth characteristics of young, planted trees of Norway spruce (Picea abies (L.) Karst), a species that forms the backbone of the Norwegian forestry sector. The study focused on well-established, sufficiently stocked plantations to capture their inherent growth patterns. The presented models predict total tree height and the number of years required to reach a diameter at breast height of 5 cm for dominant and average-sized individuals, using common tree- and stand-level metrics. The study’s findings indicate enhanced growth of young spruce stands compared to growth dynamics observed in the 1960–1970s, likely due to improved growing conditions. The models presented here are an improvement over existing similar models and can be used in future forest growth and yield simulations. The study also aimed to provide a means to predict diameter distributions of young spruce plantations. While the results suggested significant differences between observed and predicted distributions, this still represents progress as there are currently no tools to estimate diameter distributions of young spruce plantations in Norway. Further research is recommended to corroborate the findings across a larger number of sites and to consider larger sample plots for potentially more accurate diameter distribution predictions.
Sammendrag
Rapporten beskriver mulig metode for kartlegging av reinbeiter, her definert av fire årstidsbeiter. Utgangspunktet er kartlegging av vegetasjon-/naturtyper som kobles til reinens foretrukne diett gjennom året. Kartleggingen kan utføres ved feltkartlegging, fjernmåling, modellering eller statistiske utvalgsundersøkelser. Modellen som ligger til grunn for å klassifisere et areal som viktig beiteareal er kun basert på vegetasjon-/naturtypenes forventede egnethet som fôrgrunnlag for rein. I praksis vil reinens faktiske arealbruk ha mye å si, og den kan ikke kartlegges gjennom beitekartlegging. Beitekartlegginga sin viktigste funksjon som verktøy ved vurdering av reinbeiteareal, for eksempel i konsekvensutredninger, er å gi en systematisk oversikt over arealene. Beitekartlegging kan ikke erstatte reindriftsutøvernes kunnskap om reinens arealbruk, men være et supplement når en skal vurdere hvilke konsekvenser et tiltak kan få for reindriftsnæringa. Metoden er beheftet med mange usikkerhetsmomenter og må prøves ut og vurderes gjennom uttestinger.
Sammendrag
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Sammendrag
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Sammendrag
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Sammendrag
Climatic drought and changes in precipitation patterns are key features of the ongoing and predicted climatic changes in northern latitudes such as the boreal forest of Norway. Recent droughts highlight on the possible difficult future of spruce forests in southern Norway. To better understand and monitor these forests under a more extreme climate, it is crucial to gain a better understanding of the water relations of spruce trees across forest stands. Sap flow sensors are typically used for directly measuring the water demands for transpiration in individual trees. There are however limitations to their use in examining the hydraulic and physiological responses to extreme water supply variability: i) manufactured high-resolution sensors such as those following the Heat Ratio Method (HRM) or Heat Field Deformation (HFD) are expensive, limiting their deployment to a few trees in a stand, and ii) the sap flow sensors only measure the movement of water within the active sapwood, not accessing other physiological mechanisms and responses (radial growth, water storage) associated with stress response. Point dendrometers have become increasingly used, monitoring sub-daily stem size fluctuations resulting from both seasonal patterns of radial growth increment and the dynamics of plant tissue water balance. Manufactured point dendrometers are much cheaper to buy and easier to install and maintain than manufactured sap flow sensors. They can therefore be much more extensively deployed across forest stands. We aimed to analyse the relationship between sub-daily stem diameter changes and sap flow using point dendrometers and HRM sap flow sensors installed in a Norway spruce forest located 50 km north of Oslo, Norway. We linked these relationships with individual tree physical attributes, meteorology and soil climate over two growing seasons in 2022 and 2023. Our goal was to assess whether a predictive model of sap flow could be built from measured diameter changes, tree properties and climate, to ultimately reduce the uncertainty of stand level transpiration estimation at the daily resolution across entire forest stands.