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.
2025
Forfattere
Frank Thomas Ndjomatchoua Richard Olaf James Hamilton Stutt Ritter Atoundem Guimapi Luca Rossini Christopher A. GilliganSammendrag
Empirical field data and simulation models are often used separately to monitor and analyse the dynamics of insect pest populations over time. Greater insight may be achieved when field data are used directly to parametrize population dynamic models. In this paper, we use a differential evolution algorithm to integrate mechanistic physiological-based population models and monitoring data to estimate the population density and the physiological age of the first cohort at the start of the field monitoring. We introduce an ad hoc temperature-driven life-cycle model of Bemisia tabaci in conjunction with field monitoring data. The likely date of local whitefly invasion is estimated, with a subsequent improvement of the model’s predictive accuracy. The method allows computation of the likely date of the first field incursion by the pest and demonstrates that the initial physiological age somewhat neglected in prior studies can improve the accuracy of model simulations. Given the increasing availability of monitoring data and models describing terrestrial arthropods, the integration of monitoring data and simulation models to improve model prediction and pioneer invasion date estimate will lead to better decision-making in pest management.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Upgrading biogas to biomethane could contribute to sustainable energy production, yet H2S may reduce the process efficiency and gas quality. This work examined the impact of H2S on biomethanation in batch assays and in continuous trickle bed reactor (TBR). The batch assay (not biofilm based) was conducted to quickly determine the threshold H2S concentration and to evaluate the inoculum's response to repeated H2S exposure. In contrast, the TBR experiment aimed to explore the role of biofilm-based biomethanation in mitigating H2S inhibition. Batch assays revealed significant inhibition, especially at higher H2S concentrations (3 %) and thermophilic temperatures (51 °C). In the batch assay, presence of H2S resulted in up to 30 % reduction in CH4 yield, decreasing from 229 to 160 NmL/Lreactor. Additionally, the CH4 content declined by 12 %, from 49 to 43 %. In contrast, TBRs showed resilience where TBRs fed with H2S-rich biogas produced effluent gas with 83.5 % CH4, similar to control (81.0 %). 16S rRNA analysis highlighted shifts toward sulphate reducing and sulphur oxidizing bacteria under H2S exposure, while acetogenic and syntrophic acetate-oxidizing bacteria increased in the control. This suggests potential competition for available substrates when subjected to H2S. These findings highlight that H2S significantly inhibits non-biofilm-based biomethanation, as seen in batch assays, although moderate acclimation was observed. However, biofilm-based process, e.g TBRs, effectively mitigate H2S toxicity, ensuring efficient biogas upgrading to biomethane.
Sammendrag
Sweet cherry fruit in Norway is sold to the domestic market for fresh consumption. Gradually the self-fertile and high yielding cultivar ‘Lapins’ has become dominant and in the 2024 season, cv. Lapins made up 60% of the total sweet cherry volume. The production of sweet cherry in Norway is located around three main packinghouses with minor to no differences in ripening time dependent on the weather conditions of the year. Situations with too much fruit on the market at the same time have been experienced, and fruit with a longer possible distribution time have been demanded from the packinghouses. In postharvest experiments, deliveries to the same packinghouse the same day exposed to exactly the same treatments were compared and differed in fungal decay from less than 5% to 60% after simulated shelf life. The dominating fungal decay was Mucor rot and grey mold. The risk of fungal decay pre- and postharvest on fruit grown in a humid climate (500 to 1700 mm annual precipitation) increases with high humidity under the plastic cover, with fruit-to-fruit contact in clusters, with incidence of non-developing or damaged fruit, and with minimal effect of the plant protection program. In order to improve the market situation in Norway, postharvest treatments alone are probably not enough. A holistic approach is needed through introduction of new cultivars with high yield potential that ripen over a longer period of time and are thoroughly tested in real scale experiments simulating distribution. A major challenge will be how to motivate growers to plant cultivars with potentially less income than possible with the self-fertile, high yielding cv. ‘Lapins’.
Forfattere
Injeong Kim Lone Ross Gry Alfredsen Olov Karlsson Elif Kaynak Oisik Das Dennis Jones George I. Mantanis Dick SandbergSammendrag
Scots pine (Pinus sylvestris L.) sapwood was modified using maleic anhydride (MA) and sodium hypophosphite (SHP) to improve its durability against wood-deteriorating fungi, mechanical strength, and fire retardancy (thermal stability). The modification significantly reduced mass loss caused by wood-decaying fungi (Trametes versicolor, Rhodonia placenta, and soft rot fungi) due to the formation of cross-links between wood, MA, and SHP, which limited the moisture uptake and altered the chemical structure of wood. On the other hand, the modification did not provide improved resistance to fungi growth on the wood surface, which indicated that the modification had little impact on the accessibility of nutrients on the surface. A bending test showed that the modulus of elasticity (MOE) was not affected by the treatment, whilst the modulus of rupture (MOR) decreased to half the value of untreated wood. Thermal resistance was improved, as demonstrated by micro-scale combustion calorimeter testing, where the total heat release was halved, and the residue percentage nearly doubled. These results indicate that phosphonate protects the modified wood via the formation of a protective char layer on the surface and the formation of radical moieties. Based on the results, wood modified with MA and SHP shows potential for possible use in outdoor, non-loadbearing structures.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Since the 1950s, the use of plastics in agriculture has helped solving many challenges related to food production, while its persistence and mismanagement has led to the plastic pollution we face today. A variety of biodegradable plastic products have thus been marketed, with the aim to solve plastic pollution through complete degradation after use. But the environmental conditions for rapid and complete degradation are not necessarily fulfilled, and the possibility that biodegradable plastics may also contribute to plastic pollution must be evaluated. A two-year field experiment with biodegradable mulches (BDMs) based on polybutylene adipate terephthalate (PBAT/starch and PBAT/polylactic acid) buried in several agricultural soils in mesh bags showed that also under colder climatic conditions does degradation occur, involving fragmentation after two months and depolymerization by hydrolysis, as shown by Fourier-transform infrared spectroscopy. The phytopathogenic fungus Rhizoctonia solani was found to be associated with BDM degradation, and the formation of biodegradable microplastics was observed throughout the experimental period. Between 52 and 93 % of the original BDM mass was recovered after two years, suggesting that accumulation is likely to happen in cold climatic regions when BDM is repeatedly used every year. Mass loss followed negative quadratic functions, implying increasing mass loss rates over time. Despite the range of climatic and edaphic factors, with various agricultural practices and vegetable productions at the study locations, the parameters that significantly favored in situ BDM degradation were higher soil organic matter content and temperatures.
Sammendrag
Urban agriculture (UA) is increasingly recognized as a key component of sustainable cities. Commercial farmers in urban areas benefit from a large customer base, short transport distances, and access to diverse sales channels. However, high pressure on land resources makes it difficult for farmers and decision makers to find suitable areas for UA. This study ranks urban and peri-urban farmland areas based on their suitability for urban agriculture (UA) and identifies opportunities for extending the area for UA to currently unused farmland. Through collaboration with urban farmers, we identified four key themes and eleven criteria, which were weighted for two sales scenarios: on-farm and off-farm. We performed a GIS-based multi-criteria decision analysis (MCDA) and assessed suitability using the technique of order preference similarity to the ideal solution (TOPSIS) on 1 × 1 km grid cells. By overlaying the suitability maps with presumably unused farmland (PUF), we identified areas with high potential for extending UA. In the City of Bergen, 15.3 % (on-farm; off-farm=14 %) of the total farmland is both unused and highly suitable for UA, compared to only 2.8 % (on-farm; off-farm=2.4 %) in Oslo. Assessing the suitability of agricultural land for UA can support spatial planning, protect agricultural topsoil from urban expansion, and help achieve global, national, and local goals for urban farming and sustainable land use.