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.
2008
Forfattere
Gert Andersson Patrik Flisberg Bertil Lidén Mikael RönnqvistSammendrag
We describe the decision support system RuttOpt, which is developed for scheduling logging trucks in the forest industry. The system is made up of a number of modules. One module is the Swedish road database NVDB, which consists of detailed information of all of the roads in Sweden. This also includes a tool to compute distances between locations. A second module is an optimization routine that finds a schedule, i.e., set of routes for all trucks. This is based on a two-phase algorithm where linear programming and a standard tabu search method are used. A third module is a database storing all relevant information. At the center of the system is a user interface where information and results can be viewed on maps, Gantt schedules, and result reports. The RuttOpt system has been used in a number of case studies and we describe four of these. The case studies have been made in both forest companies and hauling companies. The cases range from 10 to 110 trucks and with a planning horizon ranging between 1 and 5 days. The results show that the system can be used to solve large case studies and that the potential savings are in the range 5%¿30%. Nous décrivons le système d¿aide à la décision RuttOpt, qui a été développé pour planifier le déplacement des grumiers dans l¿industrie forestière. Le système est composé de plusieurs modules. La base de données des routes suédoises (NVDB), qui contient des informations détaillées sur toutes les routes de la Suède, est l¿un de ces modules. Ce module contient également un outil qui permet de calculer la distance entre deux endroits. Un deuxième module est constitué d¿un sous-programme d¿optimisation qui permet de générer un calendrier de transport, c.-à-d. un ensemble de trajets pour tous les camions. Cette opération est réalisée à l¿aide d¿un algorithme à deux phases dans lequel la programmation linéaire et une méthode de recherche tabou standard sont utilisées. Le troisième module est une base de données qui permet d¿emmagasiner toutes les informations pertinentes. Au c@our du système se trouve u interface utilisateur qui permet de visualiser les informations et les résultats par le biais de cartes, de graphiques de Gantt et de rapports des résultats. Le système RuttOpt a été utilisé dans le cadre de plusieurs études de cas et nous décrivons quatre de ces études. Les études de cas ont été réalisées chez des compagnies forestières et des entreprises de transport. Selon le cas, le nombre de camions varie de 10 à 110 et l¿horizon de planification d¿un à 5 jours. Les résultats montrent que le système peut être utilisé pour résoudre des études de cas de grande taille et que les économies potentielles sont de l¿ordre de 5 % à 30 %.
Sammendrag
A possible cost-effective real-time patch spraying implementation against seed-propagated broad-leaved weeds in cereals is a camera mounted in front of the tractor taking images at feasible distances in the direction of travel, on-board image analysis software and entire boom switched on and off. To assess this implementation, manual weed counts (0.25 m(2) quadrats) in a 1.5 m x 2 m grid, were used to simulate camera outputs. Each quadrat was classified into 'spray' and 'not spray' decisions based on a threshold model, and the resulting map defined the 'ground truth'. Subsequently, 'on/off' spraying at larger control areas where sizes were given by the boom width and image distance, and spraying decision controlled by weed status at the single quadrat simulating the camera's view, were simulated. These coarser maps were compared with 'ground truth', to estimate mapping error (area above threshold not sprayed), spraying error (area below threshold sprayed), total error (sum of mapping and spraying error) and the herbicide reduction. Three levels of the threshold model were tested. Results were used to fit models that predict errors from boom width and image distance. Size of control area did not on average affect the magnitude of the simulated herbicide reductions, but the bigger the control area the higher the risk that the simulated herbicide reduction deviate from the reduction in 'ground truth'. Mean simulated herbicide reductions were 42-59%, depending on threshold level. Only minor differences due to threshold level were seen for mean mapping and spraying errors at given spraying resolutions. Using original threshold level and image distance 2 m, predicted total errors for boom widths 2 m, 6 m, 20 m and 40 m would be 6%, 10%, 16% and 17%, respectively. Results indicate that control area should not exceed about 10 m 2 if acceptable total error is maximum 10%.
Forfattere
Olafur Eggertsson Per Holm Nygaard Jens Peter SkovsgaardSammendrag
The last late glacial from 22,000 up until just before 13,000 years ago was very cold and dry throughout Europe. Large ice sheets were present over much of northern Europe, and ice caps covered the Alps and the Pyrenees. Forest and woodland were almost non-existent, except for isolated areas of woodland vegetation and close to the mountain ranges of southern Europe. Instead, a sparse grassland or semi-desert covered most of southern Europe, at the same time as a mixture of the dry, open steppe tundra and polar desert covered the parts of northern Europe not occupied by ice sheets (Figure 1). Ice-wedge geomorphological features suggest that permafrost extended across most of Europe, down to about the latitude of central France. At this time drifting sand and wind erosion were common in north and central Europe.
Sammendrag
The Fusarium genus includes devastating plant pathogenic fungi that cause diseases in cereals around the world. They produce several mycotoxins, including the estrogenic compound zearalenone. To better understand the molecular mechanisms determining zearalenone production, we performed differential display RT-PCR under conditions where Fusarium graminearum and F. culmorum produced high amounts of zearalenone. We found 133 expressed sequence tags (ESTs) and 54 of these were considered to be up-regulated during high zearalenone production. Several of the ESTs were confirmed to be up-regulated by real-time qPCR, but none showed any significant down-regulation in the zearalenone negative mutant Delta PKS4-T9, or were similar to typical gene expression patterns of previously described zearalenone-related genes. Some of the up-regulated ESTs were similar to genes involved in secondary metabolite production, lipid metabolism, transcriptional activation, provision of precursors, signal transduction, transport or detoxification. Several of the ESTs were also located adjacent to one another in the genome and therefore might represent genes involved in the same biosynthetic pathway. Members of six such putative pathways could be found. All sequences were compared to the MIPS F. graminearum Genome Database to verify autocalled gene predictions experimentally and to introduce new exons and gene structures.
Forfattere
Espen Tangen Aarnes Geir Østereng Michael Schneider Toumo Ollila John D. C. Linnell John Odden Jenny Mattisson Vegar Pedersen Jon Ove Scheie Aleksander Rykov Anatoly Khokhlov Olga Makarova Natalia Polikarpova Askild Solberg Harri Norberg Valery Barcan Arnodd HåpnesSammendrag
Rovdyr har alltid vært et fascinerende tema, med evne til å skape stort engasjement. Rovdyr er også en kilde til konflikter, men konfliktnivået varierer sterkt mellom de ulike Barentslandene. Dette er blant annet forårsaket av store forskjeller i distriktspolitikk, forvaltningsstrategier og ertsatningspraksis mellom de fire landene. Rovdyrkonfliktene i Norge er et yndet tema for media, og noe som skaper sterke følelser hos flere enn de som mister sau og rein. NRK sitt Brennpunkt "Offerlammene" (januar 2008) med påfølgende debattprogram var et godt eksempel på dette. I årets Barentswatch ønsker vi blant annet å belyse forskjellene i forvaltningspolitikken i Barentsregionen ved å la forvaltningsmyndigheter i de respektive land skrive hver sin artikkel.
Forfattere
Helge SjursenSammendrag
Kjempebjørnekjeks er en 2-5 m høy, toårig til flerårig skjermplante. Planten ble innført til Norge som prydplante på 1800-tallet, men er siden blitt forvillet både langs bekkefar og i skogkanter, men også i offentlige arealer, som langs veier og jernbaner, i parker/grøntanlegg, og i private hager. Kjempebjørnekjeks kan spres inn i eng og beite, men har ellers liten betydning som ugras i landbruksarealer. Plantesaft av kjempebjørnekjeks kan i kombinasjon med sollys, gi kraftig forbrenning på hud. Kjempebjørnekjeks er en fremmed art i Norge. Arten har negativ virkning på stedegent biologisk mangfold, og det er derfor behov for tiltak for å unngå ytterligere spredning. Kjempebjørnekjeks kan, ved begrenset forekomst, bekjempes mekanisk om våren ved å grave opp rotstokken ned til ca. 20 cm jorddybde. Ved større forekomster kan en bekjempe planten ved å sprøyte med Roundup (glyfosat) på 15-20 cm store rosetter, som ofte bør gjentas ut på sommeren. Dispensasjon for sprøyting inntil åpent vann må innhentes fra Mattilsynet. Den som utfører sprøyting, må ha autorisasjonsbevis, og bruke foreskrevet verneutstyr. Mekanisk bekjemping kan utføres av alle, men bar hud må beskyttes.
Sammendrag
We investigated whether the stand age affects the life span of tree and understory fine roots (<1mm) in three Norway spruce (Picea abies) stands: 30, 60 and 120-yr-old. In each stand 9 minirhizotrons were installed and images were collected once in a month throughout the growing season during the three years. Norway spruce fine roots in the 30-yr old stand had a life span 401 ± 27 and 341 ± 68 days, and understory 409 ± 162 and 349 ± 142 days, estimated by using the Kaplan Meier survival analysis (KM) and Weibull distribution, respectively...
Forfattere
Lars Tørres HavstadSammendrag
Ved leveranse av lagerfast vare til såvarefirmaet skal basis vannprosent i frøet være på mellom 11,6 og 12,5 prosent vann. Ved høyere vanninnhold enn 12,6 prosent blir det i henhold til prisavtalen trekk i oppgjørsprisen, og i verste fall må frøfirmaet tørke frøpartiet på nytt. Avleren blir da belastet med 500 kr pr. parti som må tørkes. For å undersøke hvordan vanninnholdet i frøet blir bestemt hos de ulike såvarefirmaene, og om vannbestemmelsen gir likt resultat, ble det i mars 2008 foretatt en ringtest hvor likt behandla frø ble sendt til Felleskjøpet Agri på Holstad, Strand Brænderi på Moelv og til Felleskjøpet Rogaland Agder i Stavanger for vannbestemmelse. Vedlagt artikkel omtaler resultatene fra denne testen.
Forfattere
Knut G Berdal Jihong Liu Clarke Merethe Aasmo Finne Helge Klungland Casper Linnestad Arne Mikalsen Anne Ingeborg Myhr Audun Helge Nerland Ingolf Nes Kaare Magne Nielsen Hilde-Gunn Opsahl Sorteberg Odd Egil Stabbetorp Vibeke ThraneSammendrag
Det er ikke registrert sammendrag
Forfattere
Knut G Berdal Jihong Liu Clarke Merethe Aasmo Finne Helge Klungland Casper Linnestad Arne Mikalsen Anne Ingeborg Myhr Audun Helge Nerland Ingolf Nes Kaare Magne Nielsen Hilde-Gunn Opsahl Sorteberg Odd Egil Stabbetorp Vibeke ThraneSammendrag
Det er ikke registrert sammendrag