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.
2013
Sammendrag
Information on tree species effects on soil organic carbon (SOC) stocks is scattered and there have been few attempts to synthesize results for forest floor and mineral soil C pools. We reviewed and synthesized current knowledge of tree species effects on SOC stocks in temperate and boreal forests based on common garden, retrospective paired stand and retrospective single-tree studies. There was evidence of consistent tree species effects on SOC stocks. Effects were clearest for forest floor C stocks (23 of 24 studies) with consistent differences for tree genera common to European and North American temperate and boreal forests. Support for generalization of tree species effects on mineral soil C stocks was more limited, but significant effects were found in 13 of 22 studies that measured mineral soil C. Proportional differences in forest floor and mineral soil C stocks among tree species suggested that C stocks can be increased by 200–500% in forest floors and by 40–50% in top mineral soil by tree species change. However, these proportional differences within forest floors and mineral soils are not always additive: the C distribution between forest floor and mineral soil rather than total C stock tends to differ among tree species within temperate forests. This suggests that some species may be better engineers for sequestration of C in stable form in the mineral soil, but it is unclear whether the key mechanism is root litter input or macrofauna activity. Tree species effects on SOC in targeted experiments were most consistent with results from large-scale inventories for forest floor C stocks whereas mineral soil C stocks appeared to be stronger influenced by soil type or climate than by tree species at regional or national scales. Although little studied, there are indications that higher tree species diversity could lead to higher SOC stocks but the role of tree species diversity per se vs. species identity effects needs to be disentangled in rigorous experimental designs. For targeted use of tree species to sequester soil C we must identify the processes related to C input and output, particularly belowground, that control SOC stock differences. We should also study forms and stability of C along with bulk C stocks to assess whether certain broadleaves store C in more stable form. Joint cooperation is needed to support syntheses and process-oriented work on tree species and SOC, e.g. through an international network of common garden experiments.
Sammendrag
In this letter, we advocate recognizing the genus Fusarium as the sole name for a group that includes virtually all Fusarium species of importance in plant pathology, mycotoxicology, medicine, and basic research. This phylogenetically guided circumscription will free scientists from any obligation to use other genus names, including teleomorphs, for species nested within this clade, and preserve the application of the name Fusarium in the way it has been used for almost a century. Due to recent changes in the International Code of Nomenclature for algae, fungi, and plants, this is an urgent matter that requires community attention. The alternative is to break the longstanding concept of Fusarium into nine or more genera, and remove important taxa such as those in the F. solani species complex from the genus, a move we believe is unnecessary. Here we present taxonomic and nomenclatural proposals that will preserve established research connections and facilitate communication within and between research communities, and at the same time support strong scientific principles and good taxonomic practice.
Forfattere
Roger RosethSammendrag
I perioden 2010 – 2012 har det blitt gjennomført prøvetaking av grunnvannsbrønner i 9 områder i Norge – Klepp, Kongsberg, Grue, Ullensaker/Nannestad, Nesodden, Larvik, Råde, Grimstad og Overhalla. Prosjektet er en videreføring av arbeid utført i perioden 2007 – 2009. Målet har vært å kartlegge forekomst av plantevernmidler i viktige grunnvannsforekomster i tilknytning til jordbruk. Det ble påvist plantevernmidler i 24 av totalt 28 undersøkte brønner/kilder. Midler ble påvist i alle undersøkte områder. Det ble påvist plantevernmidler i 89 av 199 analyserte prøver (45 %). Av disse overskred 24 prøver (12 %) veiledende grenseverdi for plantevernmidler i drikkevann (≤0,1 μg/l). Til sammen ble det påvist 19 ulike plantevernmidler og metabolitter. Plantevernmidlene som ble påvist i flest prøver var bentazon (35), atrazin (18), simazin (16), metalaksyl (13), MCPA (11) og BAM (11). Deretter fulgte pencykuron (6), trifloksystrobinmetabolitt (3), azyksystrobin (2), mekoprop (2) og imidakloprid (2). 13 midler og metabolitter ble påvist i konsentrasjoner over veiledende grenseverdi for drikkevann (≤0,1 μg/l). Midlene som viste flest overskridelser var bentazon (ugrasmiddel) og pencykuron (beisemiddel mot sopp). Prosjektet er finansiert over ”Handlingsplanen for redusert risiko ved bruk av plantevernmidler 2010 - 2014”. Analysene av plantevernmidler har blitt utført av Bioforsk Plantehelse, avdeling for pesticidkjemi.
Forfattere
Jolanda Roux Halvor Solheim Gilbert Kamgan Nkuekam Michael J. WingfieldSammendrag
A survey to identify ophiostomatoid fungi that infect wounds on native Norwegian and Swedish broadleaved trees was undertaken during summer 2004. A fungus resembling a species of Sporendocladia was commonly isolated from the exposed cambium and inner bark of wounds. Morphological examination and comparisons of DNA sequence data for the ITS and 5.8S regions of the rRNA gene region led to its identification as Sporendocladia bactrospora. Pathogenicity trials on young Populus tremula and Betula pubescens trees showed that S. bactrospora is capable of causing lesions on these trees. There have been few previous reports of S. bactrospora, and in most cases, these have been as saprophytes on wood. In contrast, results of this study show that it is a common inhabitant of freshly made wounds on native broadleaved trees in Scandinavia, and it appears to contribute to staining of wood.
Forfattere
Yngve RekdalSammendrag
Vegetasjonskart gjev eit bilete av den mosaikken av vegetasjonstypar som det naturlege plantedekket består av. Ein vegetasjonstype er ei karakteristisk samling planteartar som vil gå att på lokalitetar med like veksetilhøve. Ei oversikt over utbreiinga av vegetasjonstypar gjev oss på denne måten informasjon også om variasjonen i økologiske faktorar (klima, næring og vatn i jorda, snødekke og kulturpåverknad) i eit område. I tillegg kan kvar vegetasjonstype tilleggast eigenskapar med omsyn til ulik ressursutnytting og bruk (beite, slitestyrke for ferdsel, artsmangfald m.m.). I beiteområdet til Storfjellet beitelag i Ringebu og Stor-Elvdal kommunar, er det laga vegetasjonskart for eit område på 167 km². Kartlegginga er utført på oppdrag frå beitelaget. Viktigaste målsettinga er å lage eit grunnlag for planlegging av beitebruk i området. Kartlegginga er gjort etter Skog og landskap sin instruks for vegetasjonskartlegging i M 1:20 000 - 50 000. Det er framstilt vegetasjonskart og avleia temakart for sauebeite og storfebeite....
Sammendrag
Many remote sensing-based methods estimating forest biomass rely on allometric biomass models for field reference data. Terrestrial laser scanning (TLS) has emerged as a tool for detailed data collection in forestry applications, and the methods have been proposed to derive, e.g. tree position, diameter-at-breast-height, and stem volume from TLS data. In this study, TLS-derived features were related to destructively sampled branch biomass of Norway spruce at the single-tree level, and the results were compared to conventional allometric models with field measured diameter and height. TLS features were derived following two approaches: one voxel-based approach with a detailed analysis of the interaction between individual voxels and each laser beam. The features were derived using voxels of size 0.1, 0.2, and 0.4 m, and the effect of the voxel size was assessed. The voxel-derived features were compared to features derived from crown dimension measurements in the unified TLS point cloud data. TLS-derived variables were used in regression models, and prediction accuracies were assessed through a Monte Carlo cross-validation procedure. The model based on 0.4 m voxel data yielded the best prediction accuracy, with a root mean square error (RMSE) of 32%. The accuracy was found to decrease with an increase in voxel size, i.e. the model based on the 0.1 m voxel yielded the lowest accuracy. The model based on crown measurements had an RMSE of 34%. The accuracies of the predictions from the TLS-based models were found to be higher than from conventional allometric models, but the improvement was relatively small.
Sammendrag
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Forfattere
Theo RuissenSammendrag
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Forfattere
Marianne Bechmann Johannes Deelstra Sigrun Hjalmarsdottir Kværnø Anne K. Falk Øgaard Marianne Stenrød Per Stålnacke Ståle Haaland Lillian Øygarden Eva Skarbøvik Marit HaukenSammendrag
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Sammendrag
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