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.
2009
Forfattere
Paal KrokeneSammendrag
Heggspinnmøllet er en bladetende sommerfugl som har gjort mye ut av seg de siste somrene. Tidligere forekom masseangrep kun på Østlandet, men de siste 10 årene ser møllet ut til å ha spredd seg nordover.
Forfattere
Halvor SolheimSammendrag
Så lenge trær unngår angrep av skadelige organismer, kan de leve i mange hundre år. Men med alderen blir trærne mindre motstandsdyktige mot forskjellige infeksjoner, og det største problemet er gjerne råte. Råte er først og fremst et aldersfenomen. Jo eldre trærne blir, jo lettere blir de utsatt for råteinfeksjoner.
Forfattere
Halvor SolheimSammendrag
Det er ikke registrert sammendrag
Sammendrag
Insektene som forsyner seg av granas kongler og frø har tradisjonelt ikke vært regnet som noe stort problem i norske skoger. Men nå som stadig flere av granplantene som skal danne framtidas skog stammer fra frøplantasjer er dette bildet i ferd med å endre seg. Trusselbildet kan også være i endring, siden klimaet ser ut til å påvirke forekomsten av to viktige kongleinsekter, granfrøgallmygg og kongleglansvikler.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Myrmica specioides Bondroit, 1918 and Formica cunicularia Latreille, 1798 are recorded in Norway for the first time. Both species were found in 2008 at Jeløya, Østfold County in South-Eastern Norway. A total of 54 outdoor-living ant species are now known to occur in Norway.
Forfattere
Ole Martin Eklo Randi Bolli Jens Kværner Tore Sveistrup Frauke Hofmeister Eivind Solbakken Nicolas Jarvis Fredrik Stenemo Eirik Romstad Borghild Glorvigen Tor Anton GurenSammendrag
Det er ikke registrert sammendrag
Sammendrag
Growth of Norway spruce (Picea abies) trees and nitrogen deposition were analysed at about 500 forest plots throughout Norway in six fiveyear periods from 1977 to 2006. Growth was calculated from five repeated calliper measurements of all trees during this period and using treering series from increment cores of a subsample of trees. From the growth data a `relative growth` variable was extracted, being the deviation in % between observed and expected growth rates. The expected growth was estimated from growth models based on site productivity, age and stand density at each plot. The plots were categorized into four age classes. The nitrogen deposition was estimated for each plot for the same five year periods by geographical interpolation of deposition observations at monitoring stations made by the Norwegian Institute for Air Research. Nitrogen deposition from 1977 to 2006 ranged from 1 to 24 kg/ha/yr at the study plots, with about 15 kg/ha/yr in the southernmost region and 3 kg/ha/yr in the northern region of Norway. For the entire 30year period we found a long term relationship between growth and nitrogen deposition, corresponding to a forest growth increase of 0.7% per kg total nitrogen deposition per hectare and year (r2 = 0.13). This is in line with studies carried out on other data sets and for shorter time periods. This apparent fertilizing effect was most pronounced for the youngest forest, while the effect was weak for the oldest forest. The growth increase was observed in the southernmost part of Norway, the region with the highest nitrogen deposition. However, the relationship between nitrogen deposition and growth varied considerably between the time periods. In two of the periods the relationship was slightly negative: these periods corresponded well with summer droughts occurring in the southernmost part of Norway. Drought, as well as other climatic factors, will influence the shortterm variations in forest growth and may obscure the fertilizing effect of nitrogen deposition in some periods. In conclusion, nitrogen deposition has most likely increased growth in Norway spruce in southern Norway. However, our study also shows that inferences from such correlative studies should be drawn with care if the growth period is shorter than 10–15 years because climatic factors produce temporal variations in the relationship between nitrogen deposition and forest growth.
Sammendrag
The chapter reviews the available literature about the adverse effects of excess nickel on plants and their adaptation mechanisms. The study is focused on forest ecosystems exposed to extreme air pollution from the nickel-processing industry in Northern Fennoscandia. Long-term deposition of heavy metals and sulphur has caused strong soil contamination and severe damage to trees and ground vegetation, their structure, composition and chemistry. Tree leaves, branches and bark as well as dwarf shrubs, mosses and lichens show clearly elevated concentrations of nickel and copper in the surroundings of the smelters. Multivariate analyses show that changes in the element composition of plants depend both on air pollution and on natural factors. Besides direct input of pollutants from atmosphere, soil contamination and nutritional disturbance contribute significantly to the observed changes. Despite decline in emissions, extreme pool of heavy metals accumulated in surface soils is expected to influence plant metabolism and chemistry over a long period of time.
Sammendrag
There is a need to establish new objective and sensitive methods for early detection and quantification of decay fungi in wood materials. Molecular methods have proven to be a useful tool within wood protection issues, however, this field is still poorly explored and so far relatively few have used these methods within the field of wood deterioration. Among the techniques used in the indirect quantification of fungi in decayed wood and building material are chitin and ergosterol assays. DNA-based methods are rarely used for identification in connection with quantification. Access to knowledge about fungal colonisation paterns in different wood substrates would allow further improvement of new products. The aim of this study was to investigate the colonisation pattern of decay fungi in wood samples after six years in soil exposure, in an EN252 test.....