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.
2017
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Holger LangeSammendrag
Time Series, models and uncertainty: process-based and data-based approaches to environmental problems
Forfattere
Erik J. JonerSammendrag
Det er ikke registrert sammendrag
Forfattere
Frans-Jan W. Parmentier Daniel Rasse Magnus Lund Jarle W. Bjerke Bert G. Drake Simon Weldon Hans Tømmervik Georg Heinrich Hansen Lennart Nilsen Elisabeth J. CooperSammendrag
Det er ikke registrert sammendrag
Sammendrag
Målsetting med dette prosjektet har vært å bidra til en adaptiv forvaltning av dragehode (Dracocephalum ruyschiana), ved å utvikle kunnskap om artens respons på ulike skjøtselstiltak og utvikle egnede overvåkningsmetoder. Hovedmålet har vært å få økt kunnskap om artens populasjonsdynamikk i sitt nordligste utbredelsesområde med hensyn på demografiske prosesser som nyetablering (frø eller klonal), vekst, reproduksjon og overlevelse på lokaliteter med ulik hevd og skjøtselshistorikk.....
Sammendrag
Picea abies seedlings were given three different fertilization treatments in the nutrient solution by varying the potassium:nitrogen (K:N) ratios (2.5, 3.0 or 3.9 g g–1). All fertilization treatments were combined with short-day (SD) treatment or no such treatment (control). Above- and belowground growth responses in the seedlings were analyzed. The SD treatment resulted in significantly reduced shoot height, compared to untreated control, irrespective of K:N ratio. No combination of photoperiod treatment or fertilization treatment affected the root collar diameter. In the current year root fraction with diameter < 0.5 mm, the highest K:N ratio led to significantly increased root length in control plants. In each 0.1 mm root diameter class up to 0.5 mm, the highest K:N ratio significantly stimulated root growth in control plants, while the effect was less evident for SD plants. SD treatment stimulated length growth in some fine root diameter classes. We conclude that SD treatment is a good and sufficient measure to reduce height growth without compromising fine root growth of P. abies seedlings. Fertilization treatment did not significantly improve aboveground growth in SD treated seedlings, and only limited effects on root growth was seen on control plants.
Forfattere
Yngve RekdalSammendrag
Norsk institutt for bioøkonomi utførte somrene 2015 og 2016 vegetasjonskartlegging av deler av Romedal- og Stange og almenninger i Stange kommune. Samla areal var 158 km². Hele området ligger i barskog med aktivt skogbruk. Kartlegginga er gjort etter instruks for vegetasjonskartlegging i målestokk 1:20 000 - 50 000 (VK50). Det er laga vegetasjonskart og to avleda temakart for beite for sau og storfe. Denne rapporten beskriver metode for kartlegging, registrerte vegetasjonstyper og deres fordeling i området. Det er gitt en vurdering av beiteverdi og beitekapasitet. The vegetation types over a total of 158 km2 in Stange municipality have been mapped according to the methodology for vegetation mapping (scale 1:20 000 - 50 000). The whole area is in the coniferous forest, with active forestry. A vegetation map have been produced, from which two different thematic maps have been derived. This report describes the methodology and gives a detailed description of the registered vegetation types and their distribution in the area. Further, a description of other information which could be derived from the vegetation map is provided, with emphasis on grazing conditions for domestic animals.
Forfattere
Blas Mola-Yudego Javier Arevalo Olalla Díaz-Yáñez Ioannis Dimitriou Antti Haapala Antonio Carlos Ferraz Filho Mari Selkimäki Ruben ValbuenaSammendrag
Wood biomass for energy can be largely produced in northern Europe from forest land resulting from silvicultural practices and from agricultural land in the form of fast-growing plantations. The present paper estimates and compares the current regional potentials for wood biomass production attending to these sources. The data are based on spatialized estimates from previous models, largely based on empirical records concerning forest and plantation's productivity. The results show that 8.5 Mm3 of wood biomass can be produced annually from plantations when using 5% of the total available agricultural land, and 58.5 Mm3 from forest lands using current estimates of forest production. However, the results also show that a strategy for wood biomass resource management should be local rather than general: wood biomass potential from fast-growing plantations was larger in 19 regions than from forest resources (10 in Denmark, 6 in Norway and 3 in Lithuania) out of the 91 regions in the area included to this study. When considered together, northern Europe presents significant potential for wood biomass production for energy uses, and each country - and even region - should develop independent policy strategies of biomass generation in order to most efficiently realize their own potential for wood-based bioenergy.
Sammendrag
The use of digital aerial photogrammetry (DAP) for forest inventory purposes has been widely studied and can produce comparable accuracy compared with airborne laser scanning (ALS) in small, homogeneous areas. However, the accuracy of DAP for large scale applications with heterogeneous terrain and forest vegetation has not yet been reported. In this study we examined the accuracy of timber volume, biomass and basal area prediction models based on DAP and national forest inventory (NFI) data on a large area in central Norway. Two separate point clouds were derived from aerial image acquisitions of 2010 and 2013. Vegetation heights were extracted by subtracting terrain elevation derived from ALS. A large number of NFI sample plots (483) measured between 2010 and 2014 were used as reference data to fit linear models for timber volume, biomass and basal area with height metrics derived from the DAP data as explanatory variables. Variables describing the heterogeneous environmental and image acquisition conditions were calculated and their influence on the model accuracy was tested. The results showed that forest parameter prediction using DAP works well when applied to a large area. The model fits of the timber volume, biomass and basal area models were good with R2 of 0.80, 0.81, 0.81 and RMSEs of 41.43 m3 ha−1 (55% of the mean observed value), 32.49 t ha−1 (47%), 5.19 m2 ha−1 (41%), respectively. Only a small proportion of the variation could be attributed to the heterogeneous conditions. The inclusion of the relative sun inclination led to an improvement of the model RMSEs by 2% of the mean observed values. The relatively low cost and stability across large areas make DAP an attractive source of auxiliary information for large scale forest inventories.