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.
1999
Forfattere
Tone GroeggenSammendrag
Forest Officers’ Monitoring Plots. Vitality survey 1999 In 1999 totally 648 plots were assessed comprising 42088 trees (Table 2). The plots are organised in clusters of four plots subjectively chosen in different cutting classes; III (young), IV (intermediate), V (old forest) and one in declining forest. For Norway spruce a reduction in crown density of 0,7% was observed last year. The largest reduction was observed for young stands (1,4%) (Fig. 2). As usual, crown density in the western part of the country was high (Fig. 3). In mid Norway the greatest reduction was observed in old stands whereas in eastern Norway the reduction was greatest in young stands (Table 3). For Scots pine the reduction in 1999 was 1,8%, and it was particularly high in young stands (3,7%). Only in old stands a small increase in crown density was observed. As in the case of Norway spruce the greatest reduction in crown density was observed in eastern Norway. In the western part of the country an increase in crown density was observed (Table 3). For Norway spruce the number of green trees in 1999 were reduced by 1,9%, a decrease which was consistent in all stands (Fig. 4, Table 4). For Scots pine the number of green trees increased in all stands but old stands. For Norway spruce the amount of cones was generally low in 1999 (Fig. 6 and 7). For some parts of northern Norway, the largest amount of cones was observed ever since establishment in 1988. The mortality rate was 0,2%. Infection of needle rust (Chrysomyxa abietis) in mid and northern Norway was less abundant in 1999 than in 1998 and 1997. There were a number of attacks of the fungus in eastern Norway. In 1999 results from Forest officers plots are not consistent with results from Level 1 plots. There was an increase in crown density and less discolouration of trees in level 1 plots. The monitoring of forest tree vitality is motivated by the concern for negative effects due to air pollution, and hence deserves to be given priority.
Sammendrag
Hovedmålet med prosjektet var å utvikle nye rutiner for beregning av veianleggs lønnsomhet og kostnadsfordeling mellom interessentene. Lønnsomhetsberegningene gjennomføres ved å kartlegge innsparingene på grunn av redusert transportavstand før dette settes opp mot anleggskostnadene. For konstnadsfordelingen er "Hedmarksmodellen" forsøkt gjort mer eksakt ved å utvikle en nye metode for å fastsette beliggenhetsfaktoren. På bakgrunn av resultatene er det utarbeidet et dataprogram (Excel applikasjon) som utfører lønnsomhetsberegninger og kostnadsfordeling av skogsveianlegg. I programmet kan man foreta kostnadsfordelingen ved hjelp av Hedmarksmodellen eller transportgevinstmetoden. Dataprogrammmet utfører også følsomhetsanalyser hvor man tester hvordan enkeltfaktorer slår ut på hovedresultatene. Med dette kan planleggeren kunne se hvilken effekt de ulike forutsetningene gir og hvulke faktorer som har størst innvirkning på resultatene.
Forfattere
Albert WinsentsSammendrag
Det er ikke registrert sammendrag
Forfattere
Ken Olaf StoraunetSammendrag
Det er ikke registrert sammendrag
Sammendrag
The Norwegian Monitoring Programme for Forest Damage has now been running for more than 10 years. Its main objective has been to monitor forest condition in relation to air pollution. Surveys of forests are performed on plots in a nation-wide representative grid network (Level 1 in the UN/ECE ICP Forests system), in a network of local county-wise plots, and in a network of intensively monitored plots (Level 2 in the UN/ECE ICP Forests system). Vitality indicators have shown a declining trend as reported earlier, expressed as reduced crown density and more of discoloured trees, particularly in spruce forests. However, results from last year have shown a slight improvement in tree crown condition. Tree mortality in excess of normal is not recorded. Forest condition generally depends upon soil, tree age, climate, pests and diseases, and other natural impact. The observed decreased crown density since 1989 is likely caused by a harsh climate, poor soil conditions and forest diseases. Air pollution loads, add to and interact with these factors. Most likely initiating factors are needed to produce visual symptoms. Summer drought is possibly such a factor of relevance to Norway. The actual effect of the air pollution component is therefore difficult to estimate; however, its importance is not excluded. In future, possible effects of a changed global climate should also be considered. Considering these results it is reasonable to presume that most Norwegian forest ecosystems generally are still in a satisfactory condition.
Forfattere
Tore SkrøppaSammendrag
Det er ikke registrert sammendrag
Forfattere
Anne-Grete Buseth BlankenbergSammendrag
Det er ikke registrert sammendrag
Forfattere
Terje Gobakken Birger EikenesSammendrag
Det er ikke registrert sammendrag
Sammendrag
Monilinia laxa er årsak til grå monilia hos søtkirsebær (Prunus avium L.). Artikkelen er eit samandrag av undersøking av konidiedanning hos M. laxa frå overvintrande, mumifiserte frukter og fruktgreiner og frå nyleg infiserte blomar. Mumifiserte frukter som vart infiserte året i førevegen, er den viktigaste smittekjelda. Det vert danna konidiar frå slike frukter gjennom heile vekstsesongen.
Forfattere
Arve Arstein Samson ØpstadSammendrag
Verknad av sein haustspreiing, tidleg og sein vårspreiing av fast småfegjødsel på eng. Gjødselverdi, avlingsmengde og fôrkvalitet