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.
2010
Sammendrag
The Pasvik River valley is the easternmost part of Norway, and borders to Finland and Russia. In Norway it is known for its wilderness and taiga forests. During the 1960-1970s most of the mature pine forests were harvested, and large areas of pine stands have been naturally regenerated. In addition, large areas are covered with birch. The Pasvik River valley and the adjoining areas are therefore important both as an area for growing timber resources and for recreation. However, these areas have also been exposed to air pollution from Russian smelting industry since the 1930s. In addition to sulphur dioxide, emissions consist of various heavy metals which contaminate the surroundings. The main pollution source is the huge nickel plant in the Russian city Nikel, located only 10 km from the Norwegian border. For a long time there was general concern for the quality of the forest ecosystems in these areas. This concern accelerated in the mid-1980s.
Forfattere
Anders BrynSammendrag
Extensive landscape and vegetation changes are apparent within southern Norway, specifically the expansion of forests into new areas and to higher altitudes. Two main processes are believed to cause these changes: regrowth after abandoned human utilisation and recent climate changes. The purpose of this article is to elucidate ways of separating the effects of these two processes on spatiotemporal changes in the upper forest limits using examples from southern Norway. Examples from two spatial scales are implemented, a vegetation map study of a mountain region in south-east Norway and a national map-based study of south Norway. The findings show that multiple methods are necessary to understand the forest limit changes and that the research focus should be on the separation of potential drivers, specifically climate improvements and land-use changes.
Forfattere
Svein Solberg Rasmus Astrup Dan Johan Weydahl Erik Næsset Terje Gobakken Ole Martin BollandsåsSammendrag
There is an increasing need for forest resource monitoring methods, as more attention is paid to deforestation, bio-energy and forests as habitats. Most national forest inventories are based on networks of field inventory plots, sometimes together with satellite data, and airborne laser scanning (ALS) is increasingly used for local forest mapping. These methods are expensive to establish or carry out, and many countries, including some severely affected by deforestation, do not apply such methods.Satellite based remote sensing methods in use today are hampered by problems caused by clouds and saturation at moderate biomass levels. Satellite SAR is not hampered by cloud problems, and monitoring of canopy surface elevation, which is correlated to key forest resource variables, might be a future method in forest monitoring.We here present the main findings of three studies (Solberg et al. 2010, a, b, c) investigating the potential of interferometric SAR (InSAR) for forest monitoring, by describing the relationship between InSAR height above ground and key forest variables. We based this study on InSAR data from the Shuttle Radar Topographic Mission (SRTM) with its acquisition in February 2000. We obtained SRTM InSAR DEM data from DLR for two forest areas in Norway, and built a ground-truth from the combination of field inventory and ALS.The forest areas were dominated by Norway spruce and Scots pine. In each forest area we laid out a number of field inventory plots, where we recorded standard forest variables such as Dbh and tree height, and from this derived plot aggregated variables of top height, mean height, stand density (mean tree height divided by the mean tree spacing), volume and biomass. We used this to calibrate and validate ALS based models, from which we derived estimates of the same variables for each SRTM pixel. This served as reference data for the SRTM data.From the X-band SRTM digital surface model (DSM) image we subtracted a high quality digital terrain model (DTM) derived from the ALS data. This was based on an extraction of ground echoes from the data provider, and the elevations of these echoes were interpolated into a grid fitting the SRTM grid.This produced data on the RADAR echo height above ground (InSAR height), which we related to the forest variables. With digital stand maps we aggregated the variables to the stand level. The X-band microwaves penetrate a little into the canopy, and the InSAR height was on average about 1.2 m below the mean tree height. InSAR height was strongly related to all forest variables, most strongly to top height.Particularly valuable was that stem volume and biomass, ranging up to 400 m3/ha and 200 t/ha, respectively, were linearly related to InSAR height with an accuracy, RMSE, of 19% at the stand level. However, these relationships had an intercept, which represents the microwave penetration into the vegetation, and due to this the relationships were non-linear for forest stands having heights and biomass values close to zero.With a lower quality DTM derived from topographic maps, the relationships were weaker. However, as long as a forest variable is within the ranges of the linear relationship, any change in InSAR elevation would be proportional to a change in forest height, volume or biomass. And, any logging should be detectable as a sudden decrease in InSAR elevation.Hence, a forest monitoring based on X-band InSAR might be suitable even without a DTM. An application of space borne InSAR for forest monitoring would be feasible for large areas at low cost, whereas an ALS acquisition for a part of the area would serve as reference data for calibration.
Redaktører
Helmer BelboSammendrag
The OSCAR network was formed in 2005 and includes five Nordic forest research institutes Metla (Finland), Mesäteho (Finland), Skogforsk (Sweden), Skov & Landskab (Denmark) and Skog og Landskap (Norway) and SILAVA (Latvia). The network is open for all relevant research bodies in the Nordic and Baltic countries. OSCAR is one of five virtual centres of advanced research financed by the Nordic Forest Research Cooperation Committee (SNS). The main target of OSCAR is increasing the excellence and critical mass of R&D within the field of forest operations research by integrating research resources and expertise, besides promoting and developing efficient, competitive and environmentally friendly forest operation systems on a joint Nordic basis....
Sammendrag
Trebaserte produkter bidrar til å redusere klimautslipp, både ved å lagre karbon, ved å erstatte produkter som krever mye fossil energi ved produksjon og ved at det benyttes som fornybar energi. Forskningen ved Seksjon treteknologi omfatter en rekke disipliner som mykologi, treteknologi, kjemi og molekylærbiologi. Den nyeste forskningen på seksjonen bruker pulserende likestrøms elektro-osmoseteknologi (PLEOT) til å beskytte treprodukter mot soppangrep.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Anders BrynSammendrag
Kronikk som tar for seg en del problemstillinger knyttet til forholdet mellom journalister og forskere.
Sammendrag
I denne studien er det undersøkt om det er forskjeller i mengde av utvalgte næringskomponenter i produkter og beitegrunnlag fra "gamle" og "moderne" kuraser. Komponenter som ble undersøkt var blant annet fettsyrer, vitaminer og antioksidanter som plante-fenoler og -pigmenter. Som referanseprodukter ble industrielt produsert (TINE) kremfløte og seterrømme brukt.
Forfattere
Guro BrodalSammendrag
Det er ikke registrert sammendrag
Forfattere
Lena Jakob Carl AmundsenSammendrag
Denne rapporten gir et revidert forslag til terskelverdier for de 16 stoffene og stoffgruppene det er definert terskelverdier for i Veileder 1:2009. Blant disse 16 stoffene og stoffgruppene er 11 inkludert i dagens vannforskrift (vedlegg IX). Forslag til terskelverdier for 15 andre stoffer og stoffgrupper som har utslippskilder relevant for norske forhold er også utarbeidet og inkludert i rapporten. Disse stoffene (se tabell 1) ble valgt ut på bakgrunn av aktuelle norske kilder (flyplasser, veier, metall- og aluminiumsindustri, skyte- og øvingsfelt, sigevann og avløpsvann). Stoffenes fysisk-, kjemiske og biologiske egenskaper (vannløselighet, fettløselighet, toksisitet etc.) ble også lagt til grunn for valget. Terskelverdiene som er foreslått er basert på at organismer som lever i vann som er påvirket av grunnvann ikke skal påvirkes negativt over tid pga forekomst av det aktuelle stoffet. Terskelverdiene som er valgt skal være beskyttende for både helse- og miljø. Vendepunktsverdien er satt til 75 % av terskelverdien. For bekjempningsmidler og PAH anbefales det å etablere terskelverdier for enkeltforbindelser. Organismer som lever i vann setter ofte strengere krav til innhold av forurensende stoffer enn mennesker. Terskelverdier for bekjempelsesmidler, kloroform, arsen, kadmium, bly, kvikksølv, krom, nikkel, kobber og fluorid er for eksempel lavere enn dagens grenseverdier for drikkevann.