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.
1993
Forfattere
Ulf SöderbergSammendrag
Det er ikke registrert sammendrag
Forfattere
Erik NæssetSammendrag
Det er ikke registrert sammendrag
Forfattere
Isabella BørjaSammendrag
Det er ikke registrert sammendrag
Foredrag – Tålegrenser for skogsjord
Tore Frogner, Richard Frederic Wright, Jacqueline M. Esser, ...
Forfattere
Tore Frogner Richard Frederic Wright Jacqueline M. Esser Arnt-Olav Håøya G. Rudi B.J. CosbySammendrag
Det er ikke registrert sammendrag
Forfattere
Tore Frogner Arne Olav Stuanes Richard Frederic WrightSammendrag
Det er ikke registrert sammendrag
Forfattere
Richard Horntvedt Bernt-Håvard ØyenSammendrag
Det er ikke registrert sammendrag
Forfattere
B. R Singh Alhaji S. JengSammendrag
Det er ikke registrert sammendrag
Forfattere
Jens Kværner Petter D. Jenssen Tormod Briseid Tore Krogstad Øistein Johansen Ove Bergersen E.S. OlsvikSammendrag
Det er ikke registrert sammendrag
Forfattere
Mette Goul ThomsenSammendrag
Trærs vitalitet er bestemt årlig på 22 forskningsflater (2500 trær) beliggende i forskjellige deler av landet. De årlige registreringene av kronetetthet og kronefarge viste en signifikant (p<0.05) nedgang i kronetetthet på 14 av flatene siden opprettelsen. For kronefarge var det en økt misfarging på ni av flatene. Variansen i kronetetthet og kronefarge ble undersøkt i forhold til bonitet, alder, middel apriltemperatur og middel julitemperatur (stepwise regression). For kronetetthet kunne 75% av variansen forklares utifra bonitet (60%), april- og julitemperatur (11%) og alder (4%). April- og julitemperatur kunne tilsammen forklare 25% av variansen i kronefarge. En del av restvariansen kan skyldes effektene av luftforurensning. Kronetetthet var korrelert til trærnes femårige radietilvekst, men klart bonitetsavhengig. For den høyeste bonitet (G19) var det en signifikant (p<0.05) lavere tilvekst, absolutt (mm) såvel som relativ (%), med lavere kronetetthet enn for middels og lave boniteter. Tilvekst var for alle tre klassene 1% - 1.5% lavere pr. 1 % lavere kronetetthet. Dette tyder på at en nedgang i kronetetthet også medfører en nedgang i trærnes tilvekst. Femårlige endringer i kronehøyde var ikke signifikant korrelert til endringen i kronetetthet eller til absolutt kronetetthet i 1992, og endringene var generelt små.
Forfattere
Jarle BerganSammendrag
The main objection of the investigation was to study survival, height growth and injuries to plant material originating from different localities in the central pine forests of Troms and Finnmark (Fig. 1). The distance between the most northern and southern central pine forests in Troms and Finnmark is about 110 to 120 kilometres. On the other hand, the corresponding distance west to east is 400 to 450 kilometres.Previous investigations and experiences have shown that provenances from the inner parts of Troms have achieved good results as regards survival and height development when planted or sown in fjord districts and inner parts of Finnmark (Bergan 1988, 1989a). However, comparative studies of plants originating from all the main districts of pine forests have not been made before the present investigation.In the years 1974 to 1985, 21 test fields of Scots pine were laid out at different localities in the central districts of pine forests in Troms and Finnmark (Table 1). The seed was collected in Febr. - April 1973 from ten selected trees in different stands situated in eight of the most important districts of pine forests in this northern part of the country (Table 2, Fig. 1). The germination percentage of the seed was 90 to 97 per cent, except for the localities Bollo (80 %) and Slepelvli (75 %).The plots are divided into three groups. Group 1 includes plots where all or nearly all the localities of seed collection are represented (named \"main plots\"). Group 2 includes a section of the localities. The plots in Group 2 are situated at lower altitudes, while most of the plots in Group 3 are laid out at high altitudes. All plots have been frequently examined and heights measured until the autumn in 1991 or 1992.The Tables present the relative heights and survival percentages in the last year of inspection (Heikamelen, Nordreisa=100). The results of the main plots (Group 1) are shown in the Tables 3 to 5. As an average of the eight main plots, Table 6 shows the relative mean heights of all living trees (Htot) and a section of the highest trees (H20=889 trees per ha) together with the relative survival percentages.Analyses of variance and rangetests (Student-Newman-Keul = SNK) show that plants of seed from the smaller and most isolated districts of pine forests - Trany, Skibotn and Kvenangen - have less height growth and/or lower survival than plants from the larger districts: Mlselv, Nordreisa, Karasjok and Pasvik. The difference seems to increase at the frosty sites. The results of the plots in Groups 2 and 3 confirm the results of the main plots.Slepelvli in Mlselv has relatively small heights and low survival percentage, too. The locality of Slepelvli is relatively isolated from the rest of the pine forests in Mlselv. One outstanding feature of the climate at Skibotn and Slepelvli is the snow conditions, which are characterized by very little snow in the winter.One of the most frequent causes of a large decrease in plant survival of some of the seed collections at the plots has been attack from fungal diseases as Phacidium infestans and Gremmeniella abietina on the plants. Decrease in plant survival, especially in the first 5-6 years after cultivation, has been caused by physiological response due to extremely bad climatic conditions in some years. Injuries by frost, elk and hare have to a certain degree influenced the height development at some of the plots.The main conclusion of the investigation is as follows: By shortage of local seed in future cultivations in the central districts of pine forests in Troms and Finnmark, equally good survival and height growth will be achieved by using seed from the central pine forests at Mlselv, Nordreisa, Karasjok or Pasvik.