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.
2011
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
This study is a part of a larger project designed to find out the causes of top dieback symptoms in Norway spruce in SE Norway. Because sapwood tracheids constitute a water transport system while parenchyma serves as a reserve tissue (Sellin, 1991), the separation and quantification of the sapwood and heartwood may contribute to understanding of the healthy tree functioning. As the extent of sapwood is related to tree vitality, it reflects the tree growth, health and effect of environmental factors (Sandberg & Sterley, 2009). Therefore, the sapwood cross-sectional area is widely used as a biometric parameter indicating the tree vitality, although its estimation and evaluation is prone to scaling errors....
Forfattere
Knut Ole VikenSammendrag
Det ble utført en kontrolltakst av Landsskogtakseringens permanente prøveflater på Vestlandet, Trøndelag og Nordland sør for Saltfjellet i 2009. Til sammen 60 flater fordelt på 8 lagledere ble oppsøkt av en kontrollør, og samsvar og avvik for ulike parametere er vurdert. Avvik mellom lagledere og kontrollør varierer mellom de ulike parameterne. Resultatene viser at det for de fleste parametere er meget bra overensstemmelse mellom lagledere og kontrollør. Registreringene med størst avvik er elgbeite og blåbærdekningsprosent. Bestandsalder i lauvskog og kronedekningsprosent viser god overensstemmelse for mange flater, men det finnes enkelte flater med relativt store avvik. Tremålingene er generelt bra, men resultatene viser at enkelte nye innvokste trær blir uteglemt ved klavingen for flere lagledere.
Sammendrag
Ungskogpleie anses å være blant de viktigste behandlingsmessige tiltak man kan gjennomføre i skogen og med solid tradisjon i nordisk skogbruk. I denne artikkelen ser vi litt nærmere på hvordan ungskogpleie bidrar til å påvirke skogens langsiktige utvikling. Skogforskningen har siden 1950-tallet drevet systematiske undersøkelser på effektene av ungskogpleie.
Forfattere
Eirik NordhagenSammendrag
We studied drying of wood chips by surplus heat from two hydroelectric plants in the western part of Norway. The wood was chipped and loaded into the dryer; a tractor-trailer and a container were used. The dryers had perforated floors where warm air from the plants was funnelled into the dryer, using an electric fan of 4 kW. Four separate trials were conducted in September and October 2009. The drying capacity of the trailer and the container was roughly 11.5 m3 and 29 m3 loose respectively. The effective height at which drying took place was 1.2 m and 1.9 m. The average temperatures of the air channelled into the dryers was 15–18 °C in the trailer and 24–26 °C in the container. The fan was operated for 139 hours (twice) for the trailer and 121.5 and 67.5 hour periods for the container. The fan used 556 kWh (twice), 486 kWh and 270 kWh of electricity respectively. The chips located at the bottom dried first, and chips located above dried later. The water content in the chip was measured to 66.1 to 52.1% (wet base) before and 9.6 to 6.9% (wet base) after drying. The amount of water removed from the container was approximately 28 kg per hour and 22 kg per hour from the trailer. For the container, drying cost roughly 9 Euro per MWh; the cost of the trailer was nearly twice as much. This indicates that the drying volume should be as high as possible. Drying determines net calorific value and hence market value of wood chip.
Forfattere
Aparna Tiwari Adam Vivian-Smith Roeland E. Voorrips Myckel E.J. Habets Lin B. Xue Remko Offringa Ep HeuvelinkSammendrag
Background Parthenocarpy is a desirable trait in Capsicum annuum production because it improves fruit quality and results in a more regular fruit set. Previously, we identified several C. annuum genotypes that already show a certain level of parthenocarpy, and the seedless fruits obtained from these genotypes often contain carpel-like structures. In the Arabidopsis bel1 mutant ovule integuments are transformed into carpels, and we therefore carefully studied ovule development in C. annuum and correlated aberrant ovule development and carpelloid transformation with parthenocarpic fruit set. Results We identified several additional C. annuum genotypes with a certain level of parthenocarpy, and confirmed a positive correlation between parthenocarpic potential and the development of carpelloid structures. Investigations into the source of these carpel-like structures showed that while the majority of the ovules in C. annuum gynoecia are unitegmic and anatropous, several abnormal ovules were observed, abundant at the top and base of the placenta, with altered integument growth. Abnormal ovule primordia arose from the placenta and most likely transformed into carpelloid structures in analogy to the Arabidopsis bel1 mutant. When pollination was present fruit weight was positively correlated with seed number, but in the absence of seeds, fruit weight proportionally increased with the carpelloid mass and number. Capsicum genotypes with high parthenocarpic potential always showed stronger carpelloid development. The parthenocarpic potential appeared to be controlled by a single recessive gene, but no variation in coding sequence was observed in a candidate gene CaARF8. Conclusions Our results suggest that in the absence of fertilization most C. annuum genotypes, have parthenocarpic potential and carpelloid growth, which can substitute developing seeds in promoting fruit development.
Forfattere
Helmer BelboSammendrag
The theoretical potential for increased efficiency in early thinning by using accumulating harvester heads was investigated through simulation. Thinning was performed in corridors perpendicular to the strip road in 75 artificially generated stands with varying average tree size and density. The work pattern and work time in the crane work for five sizes of heads, with grapple diameters in the range of 10 to 50 cm, was estimated by the simulation model. The efficiency increased rapidly when the grapple diameter increased from two to four times the average diameter in the harvested stand, reducing the work time per tree by 15 to 50 percent compared to the single tree handling harvester head. Further increases in grapple dimension also increased the efficiency, but not at the same rate. In real work, the efficiency increase by an accumulating harvester head will probably be slightly lower due to less optimal harvesting conditions, operator skills and other non-productive work tasks that are not affected by work method.
Forfattere
Helmer BelboSammendrag
I denne rapporten gis en oversikt over tidsforbruk og kostnader i forbindelse med innsamling og bruk av halm som biobrensel i småskala fyringsanlegg. Rapporten er basert på data fra sju gårdbrukere med egne halmfyringsanlegg som i tre år har rapportert tidsforbruk og kostnader i sin halmforsyning. Seks av brukerne benyttet rundballer og sats-fyrte anlegg, mens en benyttet store firkantballer og anlegg med kontinuerlig innmating.....
Sammendrag
Langsiktige klippeforsøk ved Skog og landskap viser at både nobeledelgran og fageredelgran kan produsere mye dekorasjonsbar, mens fjelledelgran og nordmannsedelgran er svakere produsenter. Alle treslagene har imidlertid gitt mye flott bar til kransebinding. Edelgranene har god nåleholdbarhet, og nobeledelgran er i en særklasse.
Sammendrag
Det er ikke registrert sammendrag