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
Abstract
Abstract Algal cultures are widely used to study algae–bacteria interactions, yet the relative roles of algal taxonomy, culturing environment, and historical contingency in shaping bacterial communities of long-maintained monoalgal cultures remain unclear. In a two-stage experimental design, we used 16 S rRNA metabarcoding to first profile the bacterial communities of 14 filamentous freshwater algal strains from three orders (Chaetophorales, Oedogoniales, Zygnematales) maintained in two distinct culture collections, and then, in a second experiment to test community mixing using a co-culture and re-isolation design with two algal strains ( Stigeoclonium sp. and Oedogonium sp.). The 14-strain profiling showed that bacterial communities were broadly similar at higher taxonomic ranks, with many shared orders within Pseudomonadota, whereas composition at the ASV level was largely algal-strain-specific. Ordination of phylogeny-aware UniFrac distances showed that culture collection of origin explained more variation in community composition than algal order, an effect reduced but not eliminated after standardizing the culture medium. The co-culture and re-isolation experiment showed that the two algal strains exchanged many bacterial community members, yet algal strain identity remained detectable after re-isolation. These results support a framework where culture history results in strain-specific ASV-level composition within recurrent higher-rank structure, and where algal-strain-specific effects on bacterial community composition become evident when cultures are exposed to a shared bacterial pool. Co-culture followed by algal re-isolation offers a practical approach to examine the persistence of algal-culture bacterial communities under mixing and may help identify candidate bacterial partners with potentially strong host-specific interactions without requiring axenic hosts.
Abstract
Abstract Single-date UAV vegetation indices are widely used to assess potato crop performance and estimate yield. However, whether their biological interpretation remains consistent across cultivars and growth stages is rarely examined. This study investigated how the relationships between UAV-derived multispectral and thermal canopy indicators and potato yield changed during crop development under contrasting irrigation in two cultivars with contrasting maturity classes (Anouk and Celandine). UAV surveys were conducted in July and August, and canopy metrics were related to final yield and tuber traits. The relationship between NDVI and yield differed markedly between cultivars and growth stages. In the early-maturing cultivar Anouk, July NDVI showed a strong positive correlation with yield ( r = 0.87, p = 0.002), whereas August NDVI was not informative. In the late-maturing cultivar Celandine, the relationship reversed from a positive correlation in July ( r = 0.56) to a strong negative correlation in August ( r = −0.80, p = 0.009), indicating that greater late-season canopy greenness was associated with lower yield. Exploratory LOOCV Random Forest models achieved the highest yield prediction accuracy using July features for Anouk ( R 2 = 0.72) and August features for Celandine ( R 2 = 0.47), while multi-temporal features provided similar predictive performance. Greater temporal declines in NDVI were associated with higher yield in both cultivars, consistent with the change in canopy greenness acting as a phenological indicator of the transition from vegetative growth to tuber bulking. These results demonstrate that the interpretation of UAV-derived vegetation indices is strongly dependent on cultivar maturity and growth stage. A single UAV acquisition may therefore provide misleading assessments of crop performance when canopy phenology is not considered. Rather than serving as fixed proxies for yield, canopy vegetation indices should be interpreted within cultivar-specific and temporal contexts when used for potato monitoring and agronomic decision-making.
Abstract
Understanding how soil porosity varies across environmental gradients is critical for interpreting land–surface processes, including water storage, flow pathways, gas exchange, and carbon cycling. While organic carbon (OC) and soil texture are important influences on soil structure, their combined influence on porosity at landscape to continental scales remains incompletely resolved. Here, we compile topsoil datasets from Great Britain, Wales, the European LUCAS survey, and the USDA-NRCS NCSS database (n = 6335) to quantify relationships between porosity, OC, and clay content across diverse environmental conditions. Focusing on minimally disturbed soils, we evaluate individual and combined controls using generalized additive models. We develop and test simple empirical descriptors of OC:clay ratio, including a signed metric (NonCOCC) representing deviation from a reference ratio of 1 g OC to 10 g clay, positioning soils along a continuum from clay excess to OC excess. Across all regions, OC has the strongest relationship to porosity, explaining substantially more variation than OC:clay ratio metrics. NonCOCC provided a modest improvement in model performance when combined with OC and clay. Across regional datasets, the steepest portions of the fitted NonCOCC partial responses generally occurred at low positive values, suggesting a region of elevated porosity sensitivity. In a subset with aggregate-size data, this range of NonCOCC values also corresponds to a shift towards larger aggregates. This may suggest a structural pathway linking organic enrichment, aggregation, and porosity, but requires testing using data with measured OC partitions. The findings confirm importance of OC for predicting porosity and identify added value of simple metrics (NonCOCC) from widely available soil observations.
Authors
J. A. Woolliams M. Janes H. Tumas J. J. Ilska Paul McLean J. E. Cottrell J. Mackay G. GorjancAbstract
Abstract Genomics is advancing estimation of breeding values for selective breeding. Traditional pedigree information used in the estimation of breeding values can still be competitive to genomic information when markers do not adequately capture genetic variance or genomic datasets are not sufficiently large. Using the UK Sitka spruce breeding population as a study system, we assessed the accuracy of estimated breeding values using pedigree or genomic information. Nine phenotypic traits associated with growth and wood quality were measured across 1295 individuals in 50 full-sib families replicated across two plantation sites. Pedigree-based estimation was compared to genome-based estimation using identity by state (IBS) or identity by descent (IBD) information from 4123 SNPs. Accuracy of estimated breeding values was assessed using model-based standard errors, which assumes the fitted model and parameters are correct, and more objective 12-fold cross-validation by withholding some phenotypes from the model fitting. Accuracies obtained directly from the model were very similar across different types of information, but cross-validation showed genomic information gave highest accuracies for all but one of the traits. No bias was observed for any of the trait- information combinations. Results demonstrate that the estimation of breeding values with genomic information in this study system is already competitive with the pedigree information, despite evidence that the marker panel did not capture the full genetic variance. Furthermore, accuracies with genomic information have the potential to significantly improve, unlike pedigree, by increasing the size of the training set and marker density.
Authors
Vegge, ÅseAbstract
Seterdrift og bruk av utmarka til slått og beite har vore utbreitt i Noreg i lange tider, noko som har skapt unike semi-naturlege naturtypar. Men sidan 1800-talet har praksisen gått kraftig attende, og konsekvensen er at store delar av landskapet i Noreg no er i ferd med å gro att. Semi-naturlege landskap er blant dei mest artsrike økosystema i verda, og har potensiale til å bli svært produktive og gode beiteområde. Når dei opne landskapa gror att, står me i fare for å miste både det biologiske mangfaldet og beiteressursane. Det moderne jordbruket står ovanfor ei rekke utfordringar, og meir ekstensiv bruk av utmarka har blitt peika på som eit sentralt ledd i utviklinga av eit meir framtidsretta og berekraftig landbruk. Som eit ledd i dette er kunnskap om korleis me kan restaurere utmarksbeite heilt sentralt. I denne studien har eg sett på effekten av restaurering av utmarksbeite i to ulike område i Vingelen i Tolga kommune. Det eine området var fuktig, kjeldevasspåverka og dominert av høgstaudar, medan det andre området var noko tørrare og lågurtdominert. Delar av områda blei flatehogd, delar blei tynna, og delar var kontrollfelt. Beitedyr hadde tilgang til halve delen av dei to områda. Eg gjorde ruteanalysar av vegetasjonen og samla inn både arts- og miljødata. Den same datainnsamlinga har blitt gjort to år tidlegare, ei gong før hogst og tynning blei utført, og ei gong etterpå. Ved siste innsamlingsår hadde det gått tre år sidan hogst og tynning. Målet med studien var å finne ut kva type restaureringsbehandling som førte til betre beitekvalitet og auka plantediversitet i kvart av områda. Eg fann at korkje hogst, tynning og beitepåverknaden ikkje auka talet på artar, men endra artssamansetjinga i dei to områda. Kvaliteten på beitet har blitt betre som følge av hogst og tynning i det litt tørre området på grunn av auka grasdekning, og verre i det fuktige området på grunn av tilvekst av høgstaudar. I det tørrare området ser flatehogst ut til å gje den raskaste utviklinga av eng-vegetasjon og god beitekvalitet på kort sikt, men tynning kan likevel vere den beste metoden på lengre sikt ettersom flatehogst kan gje mykje strøproduksjon etter berre få år. I det fuktige området gjorde truleg rask plantevekst, høgstaudeutforming og svært lågt beitetrykk at hogst og tynning ikkje førte til betre beitekvalitet. I slike området vil det difor ikkje løne seg å rydde skogen med mindre ein har mange dyr å setje på beitet i etterkant. Tidshorisonten i dette prosjektet er likevel for kort til å sjå kva langtideffektar restaurering av utmarksbeite har. Prosjektet bør følgjast opp om nokre år for å få meir kunnskap om langtidseffektane av restaureringa som kan bli nytta i forvaltinga. Samstundes syner studien at restaurering av utmarksbeite, gjort på rett måte, også på kort sikt kan vere eit nyttig tiltak for å gjere jordbruket mindre ressurskrevjande og tilrettelagt for artsdiversitet ved å ta i bruk resursane utmarka har å by på.
Abstract
Nibio har intervjuet 14 gardbrukere i Valdres om stølsdrift. Undersøkelsen viser at økonomi og klimaendringer gjør fjellgarder med seterdrift sårbare.
Abstract
Det er ikke registrert sammendrag
Abstract
Honningblom (Herminium monorchis) er kritisk truet i Norge. Rapporten beskriver protokoll for planlagt bevaringsutsetting høsten 2026 og et standardisert opplegg for videre overvåking. Det skal etableres nye populasjoner på Herfølsalta og i Vikerkilen på Hvaler, den eksisterende populasjonen på Filletassen skal forsterkes, og det skal etableres forskningspopulasjoner på Langøya ved Langesund og Tangane i Dalen Telemark. Norsk og svensk plantemateriale brukes etter økologiske, genetiske og forvaltningsmessige vurderinger. Plantene fordeles mellom delområder og plantes enkeltvis i små klynger i faste ruter. Hvert individ får en unik ID, slik at opplysninger fra oppformering og utplanting kan kobles til seinere registreringer av overlevelse, vekst, blomstring og reproduksjon. Samtidig registreres miljøforhold, vegetasjonsutvikling og skjøtsel. Oppfølginga skal gi kunnskap om hvilke egenskaper ved plantematerialet, lokalitetene og skjøtselen som gir best etablering, og danne grunnlag for å forbedre framtidige bevaringsutsettinger av honningblom og andre trua orkidéarter.
Authors
Misganu Debella-Gilo Diress Tsegaye Alemu Richard Adade Deo D. Shirima Belachew Gizachew ZelekeAbstract
Remote sensing is essential for mapping mangrove forest ecosystems, yet accuracy and spatial resolution remain limited, particularly in Africa, where mangroves are fragmented, reference data and cloud-free images are scarce. The state-of-the-art of mangrove forest mapping relies on native-resolution imagery using machine learning. This study evaluates deep learning methods using aggregated multi-date satellite imagery to improve mangrove mapping and national-scale area estimation. Super-resolution and semantic segmentation techniques were applied to Sentinel-2 (S2) and Sentinel-1 (S1) images, with training data derived from field observations and high-resolution drone and satellite imagery. Coastal regions of Tanzania and Ghana were used as representative study areas for eastern and western Africa, respectively. Results show strong classification performance, with S2 imagery alone achieving an Intersection over Union (IoU) of 85.8%. Adding S1 provided modest gains (IoU 86.3%), while super-resolution significantly improved the accuracy (IoU 88.5%). The combined super-resolved S2 and S1 dataset yielded the highest performance (IoU 89.2%). Wall-to-wall mapping and statistically rigorous validation and area estimation produced accurate results with quantified uncertainty. Tanzania showed high consistency (F1 = 96%; 1207 km2, 95% CI [1151.7, 1263]), while Ghana exhibited slightly higher uncertainty (F1 = 92%; 92.6 km2, 95% CI [87.5, 97.7]). Integrating deep learning with multi-date, multi-sensor fusion and super-resolution enables accurate mangrove mapping and area estimation for improved coastal management and restoration.
Abstract
Solid-state anaerobic digestion (SS-AD) offers a promising route for treating lignocellulosic biomass, yet challenges remain regarding process stability, limited understanding of microbial dynamics under leachate recirculation, and insufficient integration of digestate valorization pathways. This study investigated the thermophilic co-digestion of coffee husk (CH) with avocado and flower wastes at proportions of 90:5:5 (CH + 10%) and 80:10:10 (CH + 20%) on a dry weight basis, using a leachate-recirculated SS-AD system for biogas production, while the resulting digestate was utilized for bio-briquette. The 20% co-substrate mixture (CH + 20%) produced the highest methane yield at 263 mL CH4 g−1 VS, representing a 40% improvement over mono-digested CH. The recirculated leachate maintained relatively stable pH (7.6–8.1), supported hydrolysis and prevented volatile fatty acid buildup, thereby maintaning methanogenic activity. Microbial analysis indicated that the enrichment of Firmicutes and Proteobacteria fermenters, together with Methanosarcina-dominated acetoclastic‑hydrogenotrophic methanogenesis, improved system stability during the co-digestion process. The BMP tests demonstrated that CH + 20% showed the highest methane production at 390 NmL CH₄ g−1 VS. The digestate generated from SS-AD was subsequently valorized into bio-briquettes, producing calorific values of 16.4–17.1 MJ kg−1 and improved mechanical properties that meet solid biofuel standards. This integrated approach enhances overall energy recovery from biomass residues, demonstrating the effectiveness of leachate-recirculated SS-AD for circular bioresource management.