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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.

2017

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In the city of Tromsø in northern Norway, invasive Tromsø palm (Norwegian: Tromsøpalme; English: Persian hogweed) is widespread. Although Tromsø palm has negative impacts on biodiversity and contains a phototoxic sap that burns human skin, it is also considered to be a local symbol of Tromsø city and is appreciated by many inhabitants. This study examined private landowners’ characteristics, perceptions, and landowners’ regulation of invasive Tromsø palm on their parcels on Tromsø Island in 2012 (vegetation season: May–September) to provide information concerning which landowner groups could be assisted by official regulation. Eleven key informants and 17 landowners were interviewed. Afterward, Tromsø palm on Tromsø Island was mapped using aerial photos and street-level photos from Google Maps®/Google Street View® and fieldwork verification. This distribution map was superimposed on a property map in a geographic information system to produce a map showing private parcels that contained Tromsø palm and associated neighboring parcels that did not contain Tromsø palm. Questionnaires were mailed to the 441 owners of the selected parcels, and 199 of the returned questionnaires were analyzed. Tromsø palm was more likely to be fully regulated/absent on a parcel that was inhabited (particularly if the owner lived on-site) and less likely to be fully regulated/absent if the parcel was jointly managed by several households. These findings indicate that authorities could focus their management efforts on supporting regulation efforts of those private landowners who own currently uninhabited or rented-out parcels and landowners of parcels jointly managed by several households. Furthermore, those landowners who found regulation measures against the plant on Tromsø Island important tended to have partly or fully regulated Tromsø palm on their plots. This might imply that information campaigns from authorities might encourage more landowners to regulate Tromsø palm.

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Avrenning fra jordbruket er en viktig kilde til fosfor i vassdrag i Norge. Ulike former for fosfor har ulik effekt på vekst av alger og blågrønnbakterier i vassdragene. I tiltaksanalyser er det derfor viktig å ha pålitelige estimater for både totalfosfor og andelen løst fosfat som tapes fra jordbruket. Vi har brukt data fra ni overvåkingsfelt i Program for jord- og vannovervåking i landbruket (JOVA) som har blitt overvåket i 17-25 år til å kvantifisere konsentrasjonen og andelen løst fosfat av totalfosfor i jordbruksavrenning fra ulike driftssystemer (eng og beite, åpen åker og blandete driftssystemer). Både konsentrasjonen av løst fosfat og andelen løst fosfat av totalfosfor i jordbruksavrenningen varierer sterkt mellom år. Likevel tyder resultatene på at andelen løst fosfat av totalfosfor er høyere i avrenningsvann fra driftssystemer med eng- og beiteareal (43 ± 14 %) enn i avrenningsvann fra blandete driftssystemer (30 ± 15 %) og fra driftssystemer med åpen åker (17 ± 9 %). Driftssystemene med eng- og beiteareal hadde i gjennomsnitt dobbelt så høy husdyrtetthet og høyere nedbør sammenlignet med driftssystemer med åpen åker. Disse resultatene kan bl.a. brukes som grunnlag for vurdering av faktorer for biotilgjengelig fosfor i avrenning fra ulike driftssystemer i jordbruket.

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BACKGROUND Marked effects of the climatic environment on fruit chemical composition have often been demonstrated in field experiments. However, complex covariations of several climatic factors in the natural environment complicate the interpretation of such experiments and the identification of the causal factors. This can be better achieved in a phytotron where the various climatic factors can be varied systematically. Therefore, we grew four black currant cultivars of contrasting origin in a phytotron under controlled post-flowering temperature and photoperiod conditions and analysed the berries for their ascorbic acid, sugar and organic acid contents. RESULTS The analyses revealed significant effects of genotype on all investigated compounds. Particularly large cultivar differences were observed in the concentrations of l-ascorbic acid (AA) and sucrose. The concentrations of both AA and dehydroascorbic acid (DHAA), as well as the concentrations of all major sugars, decreased consistently with an increasing temperature over the temperature range 12–24 °C. Fructose and glucose were the predominant sugars with concentrations several fold higher than that for sucrose. AA was the main contributor to the total ascorbate pool in black currant berries. The AA/DHAA ratio varied from 5.6 to 10.3 among the studied cultivars. The concentration of citric acid, which was the predominant organic acid in black currant berries, increased with an increasing temperature, whereas the opposite trend was observed for malic and shikimic acid. Quninic acid was always present at relatively low concentrations. By contrast, photoperiod had no significant effect on berry content of any of the investigated compounds. CONCLUSION It is concluded that the post-flowering temperature has marked effects on the concentration of important chemical compounds responsible for taste and nutritional value of black currant berries, whereas photoperiod has no such effect in the studied cultivars. © 2016 Society of Chemical Industry

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Bark beetles are among the most devastating biotic agents affecting forests globally and several species are expected to be favored by climate change. Given the potential interactions of insect outbreaks with other biotic and abiotic disturbances, and the potentially strong impact of changing disturbance regimes on forest resources, investigating climatic drivers of destructive bark beetle outbreaks is of paramount importance. We analyzed 17 time-series of the amount of wood damaged by Ips typographus, the most destructive pest of Norway spruce forests, collected across 8 European countries in the last three decades. We aimed to quantify the relative importance of key climate drivers in explaining timber loss dynamics, also testing for possible synergistic effects. Local outbreaks shared the same drivers, including increasing summer rainfall deficit and warm temperatures. Large availability of storm-felled trees in the previous year was also strongly related to an increase in timber loss, likely by providing an alternative source of breeding material. We did not find any positive synergy among outbreak drivers. On the contrary, the occurrence of large storms reduced the positive effect of warming temperatures and rainfall deficit. The large surplus of breeding material likely boosted I. typographus population size above the density threshold required to colonize and kill healthy trees irrespective of other climate triggers. Importantly, we found strong negative density dependence in I. typographus that may provide a mechanism for population decline after population eruptions. Generality in the effects of complex climatic events across different geographical areas suggests that the large-scale drivers can be used as early warning indicators of increasing local outbreak probability.

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The aim of the study was to investigate changes of physical, microbiological, and sensory properties of muesli with germinated fakes during storage. Germinated fakes were made from conventionally grown grains: hullless barley, hull-less oat, rye, wheat, and triticale in various proportions. Breakfast cereals samples were packaged in Doypack (stand up pouches) made from Pap50g/Alu7/ Pe60 (Pap/Alu/PE) and stand up pouches Fibrecote® HB MG 40/60 (PE/EvOH/Pap) and stored for 6 months at temperature t=35±2°C and relative air humidity φ=55±3%, to provide accelerated shelf-life testing. The main quality parameters such as total plate count, yeasts and mould, water activity, moisture content, water absorption and sensory properties—taste, aroma, consistency, and appearance were analysed using the standard methods. The results of the present experiments demonstrate that the best quality of dried breakfast cereals after storage in terms of sensory quality, microbiological stability, moisture migration, and water absorption were achieved in the Fibrecote® HB MG 40/60 pouches. This study revealed that breakfast cereals made from rye, triticale germinated triticale, germinated hull-less oat, germinated hull-less barley fakes; as well breakfast cereals made from triticale, oat, germinated wheat, germinated triticale, and germinated hull-less barley fakes packaged in Fibrecote® HB MG 40/60 can be stored for 12 months at temperature 23±2°C; but breakfast cereals made from wheat, rye, triticale, germinated hull-less oat, germinated hull-less barley, germinated rye fakes and package in same packaging material can be stored for 10 months at temperature 23±2°C.

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Regjeringen la like før jul i fjor frem sin melding "Endring og utvikling - en fremtidsrettet jordbruksproduksjon" (Meld. St. 11 (2016-17)). Meldingen kom bare fem år etter den forrige meldingen "Velkommen til bords" og er den første med en FrP-statsråd som landbruksminister. Ut fra FrPs retorikk om å slippe bonden fri, var det knyttet stor spenning til hvor langt Regjeringen ville gå i å reformere norsk jordbrukspolitikk. Dette er tema for denne artikkelen.

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This work focuses on modelling soil water reserves using an Artificial Neural Net-work (ANN). Four model variants were established based on 843 records (verifiedthrough 268 measurements) of soil water content (SWC) measured at full-scale fieldsites located in Southwest Poland. It is revealed that commonly recorded climaticdata (precipitation and temperature) linked with SWC and field water capacity(FWC) are applicable in the ANN modelling. The basic model (utilising the meteoro-logical data) was the most suitable for soil profiles with thicknesses of 0–25 cm,while in profiles with thicknesses of 0–50 cm and 0–100 cm the comprehensiveANN model (linking climatic data, FWC and SWC) was the most appropriate. Fur-thermore, comparative studies of the measured and modelled data indicated theirstatistical convergence, thus providing support for the practical implementation ofthe proposed ANN modelling.