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.
1992
Forfattere
Erik NæssetSammendrag
Formålet med dette arbeidet er å omtale anvendelser av geografiske informasjonssystemer (GIS) innen norsk skogbruk der en antar at teknologien kan gi klare nytteverdier. En ser først og fremst på anvendelser på den enkelte skogeiendom. Arbeidet er i hovedsak basert på litteraturstudier. Det redegjøres for ulike definisjoner av GIS, se kapittel 2, og økonomisk nytteverdi ved anvendelse av GIS omtales (kapittel 3). I kapittel 4 påvises det at nytteverdien av GIS-anvendelser vanligvis øker med graden av utnyttelse av det stedfestede datagrunnlaget utover den rene kartproduksjonen, samt ved gjenbruk og flerbruk av dataene. Ulike potensielle anvendelsesmuligheter av GIS innen skogregistrering, skoglig planlegging og driftsteknisk planlegging omtales i kapittel 5. Det understrekes at mange anvendelser vil være forbeholdt skogbedrifter og organisasjoner som selv har tilgang til et GIS. Når det gjelder anvendelser knyttet til skogregistrering, omfatter disse bl.a. bruk av spesialkart i forbindelse med feltarbeidet. Det påpekes også at GIS vil kunne ha en sentral funksjon i forbindelse med ajourføring av bestandskart og de skoglige dataene, og at GIS vil kunne være et integrerende verktøy mellom ulike datakilder, som tradisjonelle feltregistreringer og f.eks. satellittdata. Skoglig planlegging omfatter operativ (kortsiktig) og strategisk (langsiktig) planlegging. I den operative planleggingen kan GIS være et hensiktsmessig verktøy i årsplanleggingen; som f.eks. ved valg av bestand som skal inngå i årets sluttavvirkning. GIS er også egnet til å identifisere arealer der en ønsker å ta spesielle hensyn i skogbehandlingen, som i kantsoner rundt veier og vassdrag. Strategisk planlegging ved hjelp av GIS betinger en integrasjon mellom et GIS og en EDB-basert modell for langsiktig planlegging. Et slikt integrert verktøy gjør det mulig å innføre romlige restriksjoner i planleggingen, som f.eks. restriksjoner på hogstføringen i kantsoner. Effekten av slike restriksjoner på f.eks. balansekvantum kan beregnes. I forbindelse med den driftstekniske planleggingen drøftes bruk av GIS ved ulike former for arealklassifisering. Det nevnes eksempler på inndeling av terrenget etter tekniske og økonomiske kriterier. Bruk av GIS i forbindelse med veiplanlegging omtales også. GIS kan teknisk sett tenkes å benyttes ved alle de operasjoner som inngår i planleggingsprosessen.De store kostnadene som er knyttet til etableringen av det digitale datagrunnlaget, innebærer imidlertid at det er realistisk å utføre bare enkelte av arbeidsoperasjonene i veiplanleggingen ved hjelp av GIS. Det er antatt at mangel på GIS-kompetanse, behov for utviklingsarbeid og behov for strukturering og reorganisering av eksisterende digitale data i skogbruket er faktorer som kan være begrensende for en økende bruk av GIS i norsk skogbruk.
Forfattere
Birger HalvorsenSammendrag
Forest research has been officially organized in Norway for 75 years. The Forest Research Institute of West Norway, now located at Fana, south of Bergen, was established Jan. 1, 1916. This institution was privately financed until July, 1949, when the federal government took over. The Norwegian Forest Research Institute was established at s in 1917 as a government institution. On the occasion of their 50th anniversaries, both these institutions published comprehensive accounts, Reports of the Forest Research Institute of West Norway no. 41 (Bergen 1966) and Reports of the Norwegian Forest Research Institute vol. 24 (Vollebekk 1967), respectively. Those wishing to study more closely the origins and activities of the first 50 years of forest research are referred to these reports. In Nov. 1971, the Norwegian Parliament approved a new organizational system unifying forest research in Norway, to be known as the Norwegian Forest Research Institute. The organizational changes were initiated a year later with the incorporation of the following institutions: the Norwegian Forest Research Institute, the Forest Research Institute of West Norway, and the National Forest Survey. The latter had existed as an independent institution since 1919, and an account of the National Forest Surveys first 50 years was published in 1970. Thus, much of the forest research was established as a unit under common administration. However, a good deal of forest research is also carried out by the Forestry Institutes at the Agricultural University of Norway, partly to support their teaching, and partly in collaboration with the Norwegian Forest Research Institute. A cooperation and division of labor had gradually developed between the Forestry Institutes at the University and the Norwegian Forest Research Institute. This formed the basis for a comprehensive contract between the Agricultural University and the Norwegian Forest Research Institute, which was approved by the Department of Agriculture in 1990. This agreement resulted in the establishment of Skogforsk, which is the present designation for the official scientific and administrative collaboration between the Norwegian Forest Research Institute and the Department of Forestry of the University. The scientific cooperation consists of the personnel of the two institutions being grouped in common departments to carry out research and teaching. The administrative cooperation consists of, among other things, mutual board representation and cooperation in administrative tasks, data services, laboratories, equipment and other facilities. The aim of Skogforsk is to increase societys knowledge about the forest as an ecosystem, as well as about its use, protection and role in the economy and community life. Furthermore, Skogforsk facilitates efficient coordination and effective cooperation, as well as realization of research projects having broader goals than the institutions could have managed alone. The purpose of this special edition of Research paper of Skogforsk is to present important aspects of forest research in Norway during the last 25 years. The subject matter has been selected from a project list which each year includes ab. 120 different research activities. The final scientific reports from these projects are published either in one of the series, Communications of Skogforsk, Research papers of Skogforsk, or Bulletins of Skogforsk, or in another Norwegian or international series. A significant amount of work has been contributed by the individual authors, by the scientific editors, and, not least, by Consultant Birger Halvorsen, who has been responsible for the editing and for arranging the printing. On behalf of NISK I would like to thank everyone who has contributed to the result hereby presented. It is our hope that this publication will give an idea of the width and variety of current forest research in Norway, and that the contents will interest those assigning research tasks, collaborators, the business community, and the members of the public who use the forest and wilderness for recreation.
Forfattere
Øystein Dale Leif KjøstelsenSammendrag
Forsøkene med drift av tredeler av bjørk ble gjennomført som en del av en analyse av alternative råstoff-leveranser til sponplatefabrikken Arbor Hattfjelldal A/S. Det ble gjennomført forsøk med både motormanuell og mekaniert hogst. I forbindelse med utkjøringen ble tredelene fortrinnsvis kjørt ut sams, men sortering av virket i rot- og toppdeler ble også forsøkt. Til den mekaniserte hogsten og utkjøringen ble det benyttet en lastetraktor spesielt oppbygd for drift av tredeler. Til utkjøringen etter den motormanuelle hogsten ble det benyttet en vanlig lastetraktor. Driftsmetodene ble forsøkt i to felter med henholdvis 4,7 m3 pr. daa (felt 1) og 2,1 m3 pr. daa (felt 2). Middeldimensjonen for felt 1 var 169 dm3 og 99 dm3 for felt 2.Forsøkene viste at tredelsmetoden kan benyttes i bjørkeskog uten at det nødvendigvis må investeres i spesialutstyr. For de mest effektive systemene var forskjellen mellom mekanisert og motormanuell drift ca. 5 % (108-115 kr. pr. tonn ved 250 m kjørelengde). Hvorvidt det er lønnsomt å benytte tredelsmetoden vil være avhengig av den prisen en kan oppnå for mermassen ved levering av tredeler.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Ingegerd Dormling Øystein JohnsenSammendrag
Identical pair crosses, including reciprocals, in Pinus sylvestris L. (Scots pine) were made on ramets of the same clones in three clonal archives (seed orchards) in Sweden: Svar (64N), Rskr (59.5N), and Degeberga (56N). The offspring were used to test the hypothesis that the parental environment could affect the performance of the progeny (aftereffects). Growth and freezing tests were performed in the controlled conditions of the Stockholm Phytotron. Parental environment affected seed weight: the heaviest seeds came from Rskr and the lightest seeds, from Degeberga. Height development was affected in the two growth periods tested: seeds from Svar produced the shortest plants and seeds from Rskr, the tallest plants. There was an effect on the autumn frost hardiness in the first growth period that disappeared after the second growth period. The most hardy progenies came from Svar. The aftereffects of the parental environment were less than the maternal effects on seed weight and also less than the effects of full-sib families on growth and autumn frost hardiness. Small but mostly significant reciprocal effects were found for height and height increment during the second growth period. There was a significant reciprocal effect for seed weight. Seed weight differences could explain only a small part of the effects on growth and none of the effects on hardiness.
Forfattere
Reidar Skaar Halvor WesternSammendrag
Forest truck roads are necessary in order to carry out proper management of a forest area. In the Nordic countries there is now 400.000 km with forest truck roads. Based on a pilot study it was obvious that the conditions of the forest truck roads were not satisfactory from a road maintenance and vehicle transportation point of view.Unsatisfactory standards of bearing capacity, surface course, base course, geometric alignment were observed as major problem areas. Most of these problem areas might be solved by use of better methods and equipment for maintenance and rehabilitation of forest truck roads. Different methods and equipment for measuring the bearing capacity were tested.Use of the falling mass deflectometer (fig. 5) with a falling mass of 14 kg and a drop height of 1 m seems to be an effective method for measuring the bearing strength of forest truck roads. A simple method for analyzing gravel deposits out in the field is developed. This method makes it more relevant to put more emphasis on the quality and composition of the gravel material used for surface and combined surface/base course layers.Mixing on the road of two moraine materials which each has less satisfactory specification band is tried. The mixed material achieved an almost satisfactory specification band. The cost for transport, mixing and levelling on the road amounted to 20 SEK per m3 mixed material. Mixing of two moraine materials in the pit has also been tried. The cost of the mixing operation was 6,20 SEK per m3 mixed material.Research on surface and combined surface/base course layers with stone sizes until 100 mm showed interesting results. Use of such coarse materials give cheaper material and maintenance cost for the road. However, coarse materials might give increased cost for placing and levelling of the materials on the road. Coarse materials with maximum stone size of 70 mm seems to give good overall results on forest truck roads with small and average traffic, that is 0-30 vehicle passes per day.Production of crushed stone materials to be used on forest truck roads has been investigated. Crushing of moraine to 0-60 mm material by use of a mobile crusher showed a production of 53 m3 of crushed material per effective hour. The cost was calculated to 13 FIM per m3 crushed material. When crushing to 0-30 mm the production was reduced to 21 m3 and the cost increased to 24 FIM.Maintenance of fine gravelrich (0-20 mm) surface courses with farm tractor equipment is investigated. This equipment is effective when the task is to remove holes and ruts on the road surface which are not deeper than 3 cm. If the task is to remove deeper holes and ruts a 12-14 ton grader is more efficient. Maintenance of coarse (0-70 mm) surface courses requires a 14-16 ton grader. After the grading the road surface should be compacted with a 5 ton vibrating compactor. Compacting with a vibrating compactor equipped with rings (fig. 19) gave good results on coarse gravel materials.Use of bitumenous materials on forest truck roads has been investigated. On forest truck roads with little traffic spraying of a bitumenous emulsion gave almost maintenance-free road surfaces for until 7 years. On roads with average and greater traffic use of oil gravel can be economically justified especially on the steeper gradients.Trials with open top culverts indicate that these are efficient on 10-16% gradients but only on roads with so minor traffic that grading is very seldom carried out. Rehabilitation for forest truck roads with grader and wheeled front-end loader (shovel) is investigated. This resulted in two improvements of the front-end mounted implements used by the shovel.Forest truck road rehabilitation with farm tractor equipment has also been investigated in the project. This type of equipment is quite effective for light rehabilitation tasks.
Forfattere
Bjørnvald ArnøySammendrag
I denne rapporten legges det fram resultater fra et forsøk med planting av gran på vegetasjonsrik innmark, der planteplater av papp ble benyttet for å begrense skadevirkningen av vegetasjonen. Planteplater blir i forsøket sammenlignet med 3 vanlig brukte metoder ved planting på vegetasjonsrik mark, - nemlig urørt vegetasjon, rydding med sigd i planteflekkene og flekksprøyting av vegetasjonen. Foruten resultater fra granplantenes høydeutvikling inneholder rapporten resultater vedrørende planteskader, planteavgang, metodenes effektivitet i forhold til vegetasjonen, og planteplatenes stabilitet i forhold til vind. Ved anlegg av forsøket ble noen plater lagt løst på, mens andre plater ble festet til marken. Forsøket viste at det første året var planteplatene svært ustabile i forhold til vind. Erfaringene fra dette forsøket tyder på at det vil være nokså sjansebetont å bruke planteplater på innmark, uten at de på en eller annen måte blir festet. Dette bekreftes av resultatene fra et orienterende forsøk i Fana. Festing av platene til marken med trehaker eller små steiner virket ganske effektivt. Den første vekstsesongen var det en god del toppskader på plantene, - noe mindre for planteplater enn for de andre metodene. Seinere i forsøksperioden ble det registrert lite planteskader. Det har ikke på noe tidspunkt vært signifikante forskjeller i planteskader mellom metodene. Planteavgangen har vært relativt stor. Planteplater hadde mindre planteavgang enn rydding med sigd og flekksprøyting de første to årene. Ved avslutning av forsøket hadde dette jevnet seg helt ut. Urørt vegetasjon hadde da 30,5 % og de andre metodene 20-23 % planteavgang. Planteavgangen er ikke signifikant forskjellig mellom metodene.Granplantene i flekker som var sprøytet, hadde i slutten av forsøksperioden større høydevekst enn granplanter behandlet på annen måte. Høsten 1991 var middelhøyden for flekksprøyting (93,0 cm) signifikant større enn middelhøyden for de andre metodene. Middelhøyden for planteplater var omtrent den samme som for urørt vegetasjon og rydding med sigd (75-78 cm).
Sammendrag
Behovet for, og ønsket om å kunne mekanisere avvirkningen på Vestlandet har ført til fortsettelse av tidligere forskning ved NISK omkring prestasjonene med hogstmaskinen FMT TOR. Hensikten var å vurdere maskinens prestasjoner og begrensninger i bratt terreng i kulturskog, og sammenligne dette med tidligere forskning på Østlandet. FMT TOR er en norskprodusert, spesialbygd hogstmaskin til bruk i tynning og sluttavvirkning. Den har et FMT 45 hogst-aggregat montert på en maskinenhet med seks hjul. Prøvedrifta ble gjennomført på seks forskjellige steder i Voss kommune i løpet av seks uker i mars/april 1991. Hovedtreslaget var gran, der middeltrevolumet i de seks prøvedriftene varierte fra 255-455 dm3. Terrenghellingen varierte fra flatt til over 70 %, gjennomsnittet var ca. 30 %. Kubikkmasse pr. daa var fra 24 m3 i naturlig granskog (med innslag av furu), til 73 m3 i plantet granskog. FMT TOR gjennomførte sluttavvirkningsdriftene der en Rottne Blondin lastetraktor transporterte ut virket. TOR-maskinen ble også brukt til kvisting/ kapping ved standplass etter heltredrift med Lama SA 315B helikopter og etter heltredrift med Igland 203 Interlock slepebanevinsj. Ved slepebanedriften ble en ØSA 260 lastetraktor brukt til fremkjøring fra standplass til velteplass. Tidsstudier ble foretatt i fire av de i alt seks driftsområdene. I tillegg til å studere FMT TOR ble det også gjort studie av vinsjen, Rottne lastetraktor og helikopteret. Atskilt fra tidsstudiene ble det ført driftsstatistikk for FMT TOR, Igland 203 og begge lastetraktorene.Tidsstudiene viste at FMT TOR, gjennom driftsperioden, hadde en middelprestasjon på 21 m3/virketime, med middeldimensjon 380 dm3/tre og gjennomsnittlig terrenghelling på 27 %. I et forholdsvis jevnt terreng arbeidet maskinen seg rett oppover en gradvis brattere bakke til stigningen var ca. 55 %. Stigningen hadde ubetydelig virkning på produksjonen inntil en kom svært nær den øvre grensen. I et felt med mer ujevn overflate mislyktes maskinen i å komme forbi en kneik på ca. 65 %, der den generelle stigningen på arealet lå ved ca. 40 %.Som kvistemaskin etter slepebanedrift viste FMT TOR en gjennomsnittsprestasjon på 25 m3/virketime, der middel trestørrelse var 398 dm3. En kan trekke den konklusjon at FMT TOR arbeidet bra i forsøksfeltene opp til der terrenget satte grenser for framkommeligheten. TOR-maskinen kan være et alternativ i sluttavvirkning, men en må ha et relativt stort driftsvolum på minst 20.000 m3 pr. år, og et velorganisert arbeidsprogram for å minimalisere flyttetid mellom driftene og for å opprettholde produktiviteten.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Stein MagnesenSammendrag
The presence of genetic differences attributable to differences in geographic origin has been demonstrated in many temperate zone tree species. The variation between provenances is usually thought of as a result of natural selection. Most strongly affected by selection are characters of great importance to the trees, such as fast growth and resistance to frost. A provenance may be regarded as a climatic type adapted to the climatic conditions at the place of origin. Trees of local provenance will normally be capable of surviving without damage, but introduction of non-local provenances may lead to complete failure. Different climatic types will behave differently according to the climate of the region into which they are introduced. Experiments and field observations have shown that species and provenances transferred to an environment to which they are not adapted, will suffer physiological damage. This in turn leads to inferior growth and weakened trees. Subsequently, injuries and loss of vigour make the trees highly susceptible to pathogens and attacks by insects. Use of poorly adapted provenances may cause, not only reduced vitality and vigour in the trees, but complete destruction of whole stands. The unfortunate choice of provenance may not become apparent till trees are 20-30 years old. There can be mentioned many cases in which promising plantations have become failures at a later stage. In western Norway climatic damage and attacks of the pine needle cast fungus nearly devastated coast plantations of non-coastal Scots pine during the years 1921-23. In the same region climatic damage and disease caused destruction in stands of white spruce and lodgepole pine of interior provenance. In a field trial with Scots pine in eastern Norway nearly all trees of continental European provenance died after 29 growth seasons. In eastern Norway and the Trndelag counties dead and dying trees were observed in planted stands of Norway spruce at age 30-50 years. Investigations showed that the trees in the plantations had a growth-rhythm different from that of the local Norway spruce. An unfortunate growth-rhythm which was out of phase with the climate at the sites, was the most plausible explanation for the damage and mortality found in the plantations. Among forest injuries related to provenance climatic damage is most prominent, and in a northern country like Norway most climatic injuries are attributable to frost. Frost injuries cause reduced height growth and poor wood quality. The extent to which any particular provenance is liable to suffer damage by frost depends on the degree to which its annual growth rhythm synchronizes with the cycle of the seasons. Autumn frost affects forest trees with late and incomplete growth termination. Generally, northern provenances, high altitude provenances and continental provenances stop growing and pass into the hardy winter stage at an earlier date than southern provenances, low altitude provenances and coastal provenances respectively. The variation in resistance to autumn frost is more or less clinal, depending on the tree species. Winter frost damage frequently occurs in late winter when there is a large temperature difference between day and night. However, causal relation is often complicated. Low temperature is decisive, but other factors may be disposing or contributing. A long, mild, wet, dark autumn or a summer extremely deficient in warmth will cause insufficient maturation of tissue, and shoots will not acquire their normal frost hardiness. The predisposed shoots may then be injured by frost during the following winter. For the same reason provenances with late growth cessation and improperly matured shoots will be most liable to injury caused by winter frost. Accordingly, provenance variation in winter frost resistance will be much the same as that in autumn frost resistance. A mild winter period lowers the resistance, and later frost may cause damage. Winter frost stability resistance is the ability to maintain frost hardiness after a period of mild weather. Research indicates that this type of resistance is also under genetic control, i.e. provenance variation does exist. However, winter frost stability resistance does not correspond completely to the seasonal growth rhythm of trees. Spring frost damage is related to the time of flushing, and early flushing populations are most susceptible to frost. In general, southern provenances, low altitude provenances and coastal provenances tend to flush late, but clinal variation in spring frost resistance is hard to establish owing to substantial local variation in most tree species. Differences between species are frequently more significant than those between provenances. Southern provenances commence shoot elongation late in spring. Nevertheless, spring frost has been known to damage southern provenances more severely than those of northerly origin. It seems that populations which mature late in autumn also become more susceptible to spring frosts. On several occasions a significant relationship has been established between spring frost damage and injuries caused by autumn and winter frost. Research indicates that frost damage may also disturb the annual growth rhythm of trees. Drought damage occurs during dry periods in summer or in winter when the frozen ground prevents the trees from replacing their water loss. Constant winds will also cause drought damage. With reference to drought resistance, there are considerable differences between tree species, but provenance variation, e.g. in cuticular transpiration, does not seem to be of great consequence. For Scots pine and lodgepole pine grown in coastal areas, however, there are considerable differences between provenances in their ability to withstand desiccation by wind. Coastal provenances consistently show greater resistance to this type of damage than those of interior origin. For Norway spruce provenance is of great importance regarding stem cracks caused by late summer drought. Trees of continental European provenances are most frequently affected.Diseases caused by pathogenic fungi may seriously damage, or even kill forest trees. From field observations it would appear that many tree species are less resistant to pathogens when grown outside their natural range. Climatic conditions to which the trees are not adapted, may lead to physiological disorders which greatly reduce the capacity of the trees to withstand threats from the major pathogens. As fungi frequently enter through wounds and other injuries, frost is of great importance as a predisposing factor. This has the effect of making frosthardy provenances less prone to infection. On the whole, trees weakened by climatic injuries are apparently more susceptible to pathogens than others. As a result of experiments and field observations it would appear that in some cases resistance to disease is not related to climatic injuries. Attacks by insects may constitute a threat to the growth and vitality of forest trees. However, very little information is available regarding provenance variation in susceptibility to insect attacks. So far investigations suggest that provenance is not of great importance. On the other hand, the physiological condition of the trees will affect the ability of insects to feed and multiply. As weakened trees apparently succumb more easily to invasion pressure than others, it is of great importance to keep the forest healthy and vigorous by using well adapted provenances. Investigations indicate that air pollution may have the effect of making poorly adapted provenances even more susceptible to climatic damage. It is quite obvious that the use of well adapted provenances is a prerequisite for obtaining a healthy and vigorous forest. The occurrence of unexplainable forest injuries may be due to an unfortunate choice of provenance. It is important therefore to check the provenance of injured trees.