Hopp til hovedinnholdet

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.

2026

Til dokument

Sammendrag

Apples are dependent upon pollinators for the transfer of pollen between cultivars to ensure high quality fruit production. Agricultural intensification has reduced the availability of stable floral resources for wild bees, leading to widespread declines of important pollinators of apples. Managed honeybees are commonly used to supplement pollination services in apple orchards, but honeybees are less efficient pollinators compared to wild bees. We investigated whether increased flower abundance in the understory vegetation of apple orchards can increase pollinator activity to apple flowers. We compared bee visitation in five orchards in Eastern Norway: three unmowed orchards, and two mowed orchards. In unmowed orchards, dandelions ( Taraxacum spp.) dominated the understory vegetation. Bee observations were conducted on the understory vegetation and apple trees, via manual observations and time-lapse cameras. Wild bees preferentially visited apple flowers over dandelions, while honeybees did not differ in their visits to apple flowers and dandelion flowers. We also found that the abundance of dandelion flowers in the understory increased visits by wild bees to apple flowers. Taken together, this suggests that within orchard floral resources do not compete for pollinators but instead increase apple visitation and improve pollination success. Our results highlight the importance of managing apple orchards for wild bee populations and the potential short-term benefits of understory floral resources on apple production. Implications for insect conservation Our results show that understory vegetation should be left unmowed to increase pollination of apple flowers and provide pollinators with alternate floral resources before, during, and after apple flowering.

Sammendrag

Biochar, a carbon‐rich product of pyrolysis, is increasingly considered for soil amendment and climate change mitigation due to its potential to enhance soil properties and sequester carbon. However, its effects on tree growth in forest ecosystems remain uncertain. This study investigated the impact of biochar and nitrogen‐enriched biochar on the growth of two middle‐aged (approximately 60‐year‐old) Scots pine stands in southeastern Norway. Both stands were characterized by medium site indices and podzolic soils. In replicated field experiments, we applied four treatments consisting of an unfertilized control, and addition of biochar (2.5 t ha −1 ), nitrogen fertilizer (150 kg N ha −1 ), or biochar loaded with nitrogen (2.5 t biochar +150 kg N ha −1 ). The biochar was produced by pyrolysis of Norway spruce wood chips at 600°C. After 5 years, only treatments containing added nitrogen (either as mineral fertilizer or as nutrient‐enriched biochar) significantly increased basal area and volume growth compared to control. No significant difference in timing or magnitude of effects was observed between the nitrogen and biochar + nitrogen treatments, except better annual growth in the combined treatment the third year after fertilization, indicating rapid nitrogen release and uptake regardless of carrier. Pure biochar did not stimulate tree growth. While biochar did not negatively affect growth, its direct role as a growth stimulant was not supported under these conditions, at least in the short‐term with the dose of 2.5 t ha −1 . Further research is needed across different forest ages, site types, and application rates to fully understand biochar's potential in forestry.

Til dokument

Sammendrag

Limited information is available on cranberry crop load management. Earlier research has primarily examined flower thinning in cranberry, while the impact of fruit thinning has not yet been investigated. This study evaluated the effects of fruit thinning during early fruit development on fruit quality, return bloom, and chlorophyll fluorescence in two cranberry (Vaccinium macrocarpon) cultivars, “Pilgrim” and “Stevens.” Treatments included: (0F) removing all fruits on the upright, (1F) removing all but the lowermost fruit, (2F) removing all but the two lowermost fruits, and (C) no fruit removal (control). The majority of the non-treated uprights produced two fruits in “Pilgrim” and three fruits in “Stevens.” In “Pilgrim,” 1F resulted in heavier fruit with higher anthocyanin concentration but lower concentrations of total soluble solids (TSS) and titratable acidity (TA). In “Stevens” 1F and 2F resulted in heavier fruit but had little effect on TSS and TA, while 1F decreased fruit anthocyanin. The effects on fruit surface color were negligible. In both cultivars, return bloom was enhanced by removing all fruit on the upright indicating a strong biennial bearing tendency of individual uprights. Fruit production strongly suppressed vegetative growth of uprights in the following year, especially in “Pilgrim.” Chlorophyll fluorescence kinetic parameters decreased in 0F, indicating lower photosynthetic efficiency in the absence of fruit. The results suggest that fruit thinning is an effective approach for increasing the individual fruit weight of cranberry crop and that cranberry fruit are strong sinks that effectively suppress generative and vegetative growth of the uprights in the subsequent year.

Til dokument

Sammendrag

Green biorefineries (GBRs) aim to reduce reliance on imported feed by extracting protein from forage. Their environmental performance depends on co-product utilization, including the pulp which contains up to 70% of the original biomass dry matter. Using a life cycle assessment approach, we compared a conventional dairy system with two GBR-integrated systems differing in land availability for forage production, where pulp fraction replaced forage in cattle diets, adjusted using the Nordic Feed Evaluation System. Both GBR-integrated systems showed higher environmental impacts per kg milk than the conventional, driven by increased concentrate feed inputs or expanded land use for forage production to maintain milk production. Impact increased by up to 7% and 8% for global warming potential and land use, respectively, while other impact categories showed similar or even higher increases. Substituting soybean meal elsewhere with GBR-produced protein concentrate partially offset these impacts but was insufficient to reduce impacts below the conventional system. In a sensitivity analysis, neither a higher feeding value for pulp nor a higher-impact assumption for the avoided soybean meal alone was enough to bring impacts below the conventional system. Only when both were combined did global warming potential and land use fall below conventional, by 5%.