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.
2007
Forfattere
Anne Kristine Søvik P.T. MørkvedSammendrag
Constructed wetlands (CWs) treat municipal wastewater through the retention of nutrients and particles. The retention of nitrogen (N) was studied in the laboratory using columns and meso-scale trenches filled with shellsand and light-weight aggregates (LWA). The objective was to examine whether measuring the natural abundance of d15N in NO2 3 could be used to estimate the relative contribution of denitrification to the total NO2 3 removal in these treatment systems. In both the columns and the trenches it was seen that denitrification was more efficient in shellsand and LWA collected from on-site treatment systems compared to new LWA. This was due to the high pH value (about 10) of new LWA. The enrichment factors (e ) from the column study were in general lower than values found in laboratory tests of isotope discrimination in denitrification, but similar to e values found for denitrification in groundwater systems. No enrichment factors could be found for the trench study due to simultaneous denitrification and nitrification and inhomogeneous N transformation patterns. When NHþ4 was partially nitrified in the upper parts of the trench, this diluted the 15N enrichment of NO2 3 due to denitrification. Thus, in systems with high NHþ4 concentrations and partial aerobic conditions, the method of natural abundance is not suitable for estimating the relative contribution of denitrification to the total NO2 3 removal.
Forfattere
Anne-Grete Buseth Blankenberg Ketil Haarstad Anne-Kristine SøvikSammendrag
Agricultural runoff contributes with significant amounts of nitrogen (N) to rivers and lakes causing water quality problems. Constructed wetlands (CWs) in first- and second order streams reduce downstream loading of nutrients through mechanisms such as sedimentation, uptake by vegetation and microbial denitrification. (A stream with no tributaries (headwater stream) is considered a first order stream. A segment downstream of the confluence of two first order streams is a second order stream [1]). Norwegian CWs are often too small to easily achieve high N-retention. It is therefore important to improve and optimize the N-retention processes in the CWs where the CW area cannot be increased due to local restrictions. The main aim of this project was to compare N-retention in an experimental wetland including eight different types of organic and mineral CW-filters, one of which was a standard Norwegian CW (depth 0.5 m). The average total-N retention through the experimental wetland was 17 % for the period of May-September in 2003, but only 2% in the same period in 2004. Converted to mass, the retention in 2003 was 168 kg and 26 kg in 2004. Lower retention in 2004 was probably mainly caused by higher hydraulic load that year. The organic filters performed better than the mineral filters and the standard CW.
Sammendrag
Oil shipment in the Barents Region had insignificant volumes before 2002. In 2002, there was a dramatic increase in oil transportation, when 4 million tons of oil was shipped across the northern regions of Russia and Norway. In 2003, the volume reached 8 million tons. The trend continued in 2004, and about 12 million tons of export oil and oil products were delivered from the Russian Arctic to the western market along the Norwegian coast. In 2005 and 2006, the annual oil shipment volume was on the level of 10 million tons. The terminals loading Russian oil for export in the Barents Region have been continuously developed, and the overall shipping capacity has been enlarged. In the recent study of oil shipment in the Barents Region we gave special attention to the existing and prospective offshore and onshore oil shipment terminals and their connection to the oil reserves on one hand and to the export routes on the other. We see now that even without a trunk oil pipeline to the Barents Sea coast, the annual oil exports from the Russian part of the Barents Region may reach a volume of about 50-80 million tons in the next decade. Crude oil and oil products will be delivered to the transshipment terminals in the ice free area of the Barents Sea by railway and shuttle tankers, and further shipped to export by line tankers. Oil pollution prevention should be the central issue during oil transportation in the Barents Sea.
Sammendrag
In December 2005 a questionnaire survey was conducted at the university hospital in Trondheim, Norway. Patients and personnel expressed that food is important for their health and well-being. Good taste, appearance and right nutrition were mentioned to be important factors for food quality. About 80 % of the respondents were positive or really positive to use organic food at the hospital, even though only around half of them agreed that it is worth the price. Furthermore the absence of pesticides, artificial fertilizers and preservatives in food was ranked to be more important than organic production of food. All respondents seemed to be critical towards the use of pesticides and preservatives in food production and processing.
Sammendrag
Climate changes will increase the frequency of extreme precipitation events, floods and snow melt periods experienced by the infrastructure. According to initial analysis by the Norwegian transport sector these changes will affect road maintenance, emergency planning, design of new roads and infrastructure. Increased frequency of floods is expected to cause more closed roads because of insufficient and badly maintained drainage systems. Increased ground frost and ice formation on ground surface cause large increases in surface runoff during snowmelt. Recently, in Norway the ClimRunoff project has started with the focus on quantifying discharge of catchment areas draining towards roads. The first priority of the project is to create a model that can evaluate the run-off situations under spring situation (i.e. overland flow due to snowmelt and partially frozen soils). The model is tested on a well-defined catchment under autumn situation. Preliminary results of the model calculations will be presented, together with the challenges to alter the model to be able to calculate snowmelt and frozen soil conditions. In close cooperation with the Norwegian road authorities, areas with historical flooding events are selected, and current and future climate data will be used to analyse the infrastructure of the road construction. Together with a risk analysis of the vulnerability of the transport infrastructure the model will be used to create guidelines for
Forfattere
Anne-Grete Buseth Blankenberg Ketil Haarstad Bent C. BraskerudSammendrag
Pesticide losses to the environment are unwanted due to possible environmental and health hazards. An experimental wetland is established to study the efficiency with respect to retention of sediments, nutrients and pesticides. Pesticides were applied on an arable soil plot in the watershed. Statistical analyses were carried out on three selected pesticides; propachlor, metalaxyl and chlorfenvinfoss. All pesticides were found in the experimental wetland, with peak concenttrations shortly after spraying. In 2003 pesticide retention varied from 11% to 42% and in 2004 retention varied from 19% to 56 %. Comparing eight different wetland filters, we found that L6 and L8, with flagstones and straw, respectively, had a higher total pesticide retention than a standard Norwegian wetland (L4). When the compounds were treated separately, however, the picture was different. Statistical analyses showed that the treatments were signficantly different from zero in six of the wetlands for remowal of propachlor, for removal of metalaxyl none were significantly different, and for removal of chlorfenvinphos four treatments were significantly different. For the three compounds none of the relative treatments were significantly different from L4. Chemical properties of the pesticides could explain some of the behaviour in the watershed and in the wetland.
Sammendrag
In 2004, Phytophthora symptoms were observed on two different fir species used for Christmas trees in Norway. Isolations resulted in a Phytophthora sp. related to P. inundata from relatively newly established nordmann fir (Abies nordmanniana) and P. megasperma from seven-year-old subalpine fir (A. lasiocarpa). The nordmann fir plantation was most severely damaged, with approximately 70% of the trees dead or dying. In the field with subalpine fir, approximately 25% of the trees had yellow or brown foliage and stem canker. Pathogenicity was proven for both Phytophthora isolates on seedlings from their respective host plants. The massive infestation in the nordmann fir plantation approximately one year after planting suggests that the pathogen was introduced into the planting with the transplants. Except for a recent report of P. cambivora on noble fir (A. procera) produced for bough production (17), Phytophthora has never been reported before on fir in Norway.
Foredrag – Potensiale for kultivering av nyper i et nordlig europeisk atlanterhavsklima.
Rolf Nestby
Forfattere
Rolf NestbySammendrag
Tradisjonelt har nyper i Norge blitt høstet fra ville planter som vokser på beiter og langs åker- og skogskanter, eller på andre åpne plasser som f.eks. skredmark. Hovedsakelig har nyper blitt brukt som syltetøy eller te. Parallelt med velstandsutviklingen i samfunnet har denne tradisjonen begynt å dø ut sammen med kunnskapen om hvordan man bruker nyper. Imidlertid vokser mange arter godt og danner modne nyper av god kvalitet som synes å være resistent mot de fleste sykdommer og skadedyr. I vurderingen rundt hvordan man skal kunne utnytte denne ressursen var tanken på kultivering nærliggende. Det ble derfor sett på noen faktorer som er viktig for å lykkes. Artikkelen omhandler noen av erfaringene rundt dette i Stjørdal . Rosa dumalis er den mest vanlig arten i regionen, og er valgt som en modell for domestisering. Den er også bemerket som viktig i Sverige (Ugla & Nybom 1999), og i øst- Anatolia, Tyrkia, blir nyper høstet fra ville nyper hovedsakelig R. dumalis (Ercesli 2006 PC). Planten er opprett og har en passende høyde for hand- og maskin-høsting. Fruktavlingene er gode og stabile fra år til år, og frukten er relativt stor. Den kan bli kraftig skadet av larven til nypeflua, ellers er planten frisk.
Sammendrag
Potato mop-top virus (PMTV) is one of the most damaging viruses infecting potato due to the brown rings and arcs (spraing) it induces in tubers. In Norway the disease has spread slowly, especially in the potato growing areas of Trøndelag and southern Norway. The survival of PMTV-carrying resting spores for at least 12 years in the field complicates control measures, and once the virus has been established in a potato field eradication is unlikely. In this study, the distribution and variability of PMTV in Norway is being investigated. Soil samples (349) from all over Norway have been examined for the presence of PMTV. Bait plants of Nicotiana benthamiana and N. debneyi were used to capture PMTV from resting spores of powdery scab in the soil. PMTV was found to be present in 73% of the soil samples and occurred in all counties of Norway. To investigate the possible existence of different PMTV strains, 10 PMTV isolates from different geographical regions were characterised biologically. The results indicate that more than one PMTV strain occurs in Norway.
Forfattere
Nina Opstad Arnfinn Nes Finn MågeSammendrag
I et feltforsøk med jordbær plantet på Østlandet, ble tørrgjødsling ved planting i august 2003 sammenliknet med gjødselvatning fra mai 2004. Halve feltet ble gjødslet ved planting og ble gjødselvatnet med en lav gjødselrate fra våren etter (T1), mens den andre halvparten var ugjødslet ved planting og ble i stedet gjødselvatnet med høg gjødselrate fra våren 2004 (T2). I 2005 fikk begge leddene tilført samme mengde gjødsel. Ingen av behandlingene medførte noen mangelsymptomer i løpet av forsøket, men av alle parametrene som ble registrert, var det bare antall blad og bladareal som kompenserte for den begrensa næringstilgangen om høsten. Avling og bærstørrelse var signifikant høgere i T1 i det første avlingsåret, på tross av den lave gjødselraten i avlingsåret. Året etter ble det ikke funnet noen signifikante forskjeller mellom T1 og T2. Blad og bladstikler ble samlet flere ganger gjennom sesongen, og tørrstoff og bladsaft ble analysert for makro- og mikronæringsstoff. Det var få signifikante forskjeller mellom behandlingene, men det var en tendens til at bladsaftanalysene sa mest om det aktuelle opptaket i blad. Hverken tørrstoffanalyser eller bladsaftanalyser i sesongen gjenspeilet avlingspotensialet, da det var underoptimale forhold om høsten som reduserte bærstørrelsen i T2.