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.
2011
Forfattere
Richard Fischer Wenche Aas W. De Vries Nicholas Clarke Pavel Cudlin David Leaver Lars Lundin Giorgio Matteucci Rainer Matyssek Teis Nørgaard Mikkelsen Michael Mirtl Yasemin Öztürk Dario Papale Nenad Potocic David Simpson Juha Pekka Tuovinen Timo Vesala Gerhard Wieser Elena PaolettiSammendrag
Science-based approaches in addressing future risks and challenges for forests require close collaboration among the communities operating different monitoring and research networks as well as experts in process and large-scale modelling. Results of the COST FP0903 conference which took place in October 2010 in Rome, reveal valuable results from different European forest monitoring and research networks. However, the need for closer integration of these activities is obvious. In this paper, representatives from major European networks recommend a new approach for forest monitoring and research in Europe, based on a reasonable number of highly instrumented “supersites” and a larger number of intensive monitoring plots linked to these. This system needs to be built on existing infrastructures but requires increased coordination, harmonisation and a joint long term platform for data exchange and modelling.
Sammendrag
In recent years the harmonization of methods in the frame of the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) operating under the UNECE Convention on Long-range Transboundary Air Pollution (CLRTAP) has been intensified. Among the C-actions of the FutMon project (LIFE07 ENV/D/000218; 2009-2010) the C1-Dep-22(SI) action was established with the goal to harmonize and develop the deposition monitoring procedures and sampling methods. The sampling equipment, spatial design of sampling plots and sampling frequency throughout Europe vary considerably. Therefore a step-by-step approach was made where the harmonized sampling equipment was developed and tested first. The selected collectors were installed at one observation plot of each participating country where measurements of throughfall and bulk deposition were run in parallel with the national collectors for a period of one year. To evaluate the agreement between methods, different statistical analyses were used including Altman-Bland plots, model II regression, and repeated measures ANOVA. Preliminary results from the “Intensive forest ecosystem monitoring plot” plot Brdo in NW Slovenia show a good agreement between national and harmonized bulk (both funnel-type) collectors, while comparison of throughfall measurements indicates systematic bias between harmonized (funnel-type) and national (gutter-type) collectors.
Sammendrag
Arable weeds are generally distributed in patches, while herbicides are applied uniformly. Herbicides can be saved if only the patches are sprayed, i.e. patch spraying (PS). Bottlenecks for cost-effective PS are weed monitoring technology and valid technology-based decision rules for PS (thresholds). The novel machine vision algorithm Weedcer has been developed as an efficient weed monitoring tool for PS. Weedcer estimates the proportions of young weed leaves and cereal leaves in high resolution red–green–blue images. We conducted field trials to test relative weed cover (RWC) and relative mayweed cover (RMC) estimated by Weedcer as decision rules for PS. RWC is the total weed cover divided by the total plant cover and RMC is the mayweed cover divided by the total plant cover. The main criterion for evaluation and basis of these thresholds was the measured grain yield. Images (about 0.06-m2) were acquired with a GPS guided autonomous field robot in spring, the normal time for spraying seed-propagated broadleaf weeds in both winter – and spring cereals in Norway. Three map-based trials (weed monitoring and spraying in two separate operations) showed that mean RWC per management unit (12.0 × 12.5-m) was generally adequate. In winter wheat heavily infested with scentless mayweed (Tripleurospermum inodorum (L.) Sch.Bip.) and/or scented mayweed (Matricaria recutita L.), the mean RMC per management unit was more adequate. Progress during the project allowed three additional trials conducted in real-time (weed monitoring and spraying in the same operation). These were conducted with the robot in spring cereals, and showed that a weighted moving average of RWC per image was adequate. The sprayed and unsprayed management units in these trials were minimum 3.0 × 3.0-m and 0.5 × 3.0-m, respectively. Results indicated that the Weedcer-based thresholds should be lower in wheat (Triticum aestivum) than in barley (Hordeum vulgare).
Redaktører
John Marshall Bryden Sophia Efstratoglou Tibor Ferenczi Tom Johnson Karlheinz Knickel Karen Refsgaard Kenneth J. ThomsonSammendrag
Det er ikke registrert sammendrag
Sammendrag
Tracers can be used to monitor emisions of leachate from landfills, in order to detect hydrological pathways and to evaluate environmental pollution. We investigated the occurrence of the stable carbon isotope ratio (13C measured in dissolved inorganic carbon, or d13C-SCO2) and tritium (3H), in addition to parameters commonly found in relatively high concentrations in leachate such as chloride (Cl), organic matter (COD), nitrogen (Total and NH4-N), iron (Fe), electrical conductivity and pH. The sampling was performed at seven landfills in the south-eastern part of Norway during a period of 5 years. The objective was to evaluate the potential for tracing leachate in the environment with emphasis on groundwater pollution. By analyzing the d13C-SCO2 ratio in leachates, ground waters and surface waters the influence of leachate can be identified. The content of d13C-SCO2 varied from -5.5 to 25.9‰ in leachate, from -25.4 to 14.7‰ in groundwater, and varied between -19.7 to -13.1‰ in creeks. A comparison of the content of carbon isotope ratio with the concentrations of the compounds COD, electrical conductivity, Total- and NH4-N, Cl and Fe showed that d13C-SCO2 is a good tracer for leachate due to higher sensitivity compared to other parameters. The mean concentration of all the studied parameters was higher in the leachate samples, however, only the carbon isotope ratio showed significant differences between all of the groups strongly and weakly polluted and unpolluted samples, showing that it can be used as a practical tracer for lechate in groundwater and surface water. The carbon isotope ratioshowed strong correlation between nitrogen and electrical conductivity, and bicarbonate, but not with pH. Tritium was only found sporadically in low concentrations and is considered not suitable as a tracer at the sampled locations.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Espen Govasmark Brit SalbuSammendrag
Det er ikke registrert sammendrag
Forfattere
Vibeke Stærkebye Nørstebø Ulf Johansen Hanne Marie Gabriel Bruce Talbot Jan-Erik Ørnelund NilsenSammendrag
Hovedmålet med prosjektet er å utarbeide en prioritert investeringsplan for utbygging av tømmerkaier langs norskekysten, slik at forholdene legges til rette for en rasjonell tømmertransport fra skog til industri. Vi har benyttet matematisk programmering til å identifisere det optimale antall, størrelse og lokalisering av tømmerkaier - i dag og over en tidshorisont på 20 år. Modellen er tilpasset slik at den tar hensyn til dagens og fremtidens avvirkningsvolum, infrastruktur, kostnader og tariffer, og for øvrig andre målbare faktorer som påvirker samlede transportkostnader. Ved hjelp av modellen har vi identifisert en skissemessig plan for lokalisering, dimensjonering, og utbygging av tømmerkaier langs norskekysten, samt en følsomhetsanalyse for viktige drivere. Den viser at investeringskostnad for kaier, kundenes lokalisering og tilhørende etterspørsel, og kostnad for lastebiltransporten og endret veikvalitet / bruksklasse (foruten totalt avvirkningsvolum) har størst effekt på resultatet og totalkostnaden. Prosjektet har også vurdert andre miljø- og samfunnsgevinster av en slik utbygging langs kysten. Flere kaier (for samme mengde avvirket tømmer), og tilhørende redusert antall kilometer tømmertransport med lastebil ser ut til å være gunstig med tanke på miljøutslipp. Det er også potensial for å utvikle modellen til å analysere flere ting enn hva som ligger inne per i dag. Et aspekt som bør inkluderes er profittmaksimering (overskudd) og verdikjedeoptimering.
Forfattere
Gro EggenSammendrag
Det er ikke registrert sammendrag
Forfattere
Kyrre Linné Kausrud Jean-Claude Grégoire Olav Skarpaas Nadir Erbilgin Marius Gilbert Bjørn Økland Nils Christian StensethSammendrag
Bark beetles (Coleoptera: Curculionidae, Scolytinae) feed and breed in dead or severely weakened host trees. When their population densities are high, some species aggregate on healthy host trees so that their defences may be exhausted and the inner bark successfully colonized, killing the tree in the process. Here we investigate under what conditions participating with unrelated conspecifics in risky mass attacks on living trees is an adaptive strategy, and what this can tell us about bark beetle outbreak dynamics. We find that the outcome of individual host selection may deviate from the ideal free distribution in a way that facilitates the emergence of tree-killing (aggressive) behavior, and that any heritability on traits governing aggressiveness seems likely to exist in a state of flux or cycles consistent with variability observed in natural populations. This may have implications for how economically and ecologically important species respond to environmental changes in climate and landscape (forest) structure. The population dynamics emerging from individual behavior are complex, capable of switching between “endemic” and “epidemic” regimes spontaneously or following changes in host availability or resistance. Model predictions are compared to empirical observations, and we identify some factors determining the occurrence and self-limitation of epidemics.