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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2026

2025

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Abstract

Pollinator conservation schemes typically focus on conserving existing, restoring degraded, or creating new wild bee habitats. Their effectiveness depends on dispersal corridors enabling habitat colonization by bees. However, the role of seminatural linear landscape structures (LLS) in connecting pollinator communities across intensively managed landscapes remains poorly understood. We analyzed 953 occurrences of wild bees comprising 79 nonparasitic species sampled at 68 study sites across a Norwegian and a Danish landscape. We first tested whether bee species richness was positively associated with the lengths of seminatural LLS in bee foraging ranges of study sites while controlling for local plant species richness. We then combined maps identifying seminatural LLS with least‐cost path (LCP) analysis to determine whether bee species compositional similarity, a proxy for connectivity, decreased as LCP length increased. The length of seminatural LLS, such as forest edges, was positively correlated with bee species richness and habitat connectivity. Specifically, wild bee species richness sampled along roadsides increased as the length of seminatural LLS increased in 1.5 km circles around the study sites, and increased as local plant species richness increased. The most likely dispersal routes between our bee communities tracked forest edges. The length of LCPs provided better models of bee species compositional similarity than geographic distance, suggesting that seminatural LLS, particularly forest edges, act as dispersal corridors in intensively managed landscapes. However, bee species compositional similarity among communities depended on site‐specific plant species richness and similarity in plant community composition, which highlights the importance of improving the habitat quality of seminatural LLS if they are to function as dispersal corridors. Our findings suggest that maps of LCPs can be used to identify important dispersal corridors between bee habitats and to direct wild bee habitat management actions along seminatural LLS to facilitate the dispersal of bees in intensively managed landscapes.

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Abstract

As droughts become longer and more intense, impacts on terrestrial primary productivity are expected to increase progressively. Yet, some ecosystems appear to acclimate to multiyear drought, with constant or diminishing reductions in productivity as drought duration increases. We quantified the combined effects of drought duration and intensity on aboveground productivity in 74 grasslands and shrublands distributed globally. Ecosystem acclimation with multiyear drought was observed overall, except when droughts were extreme (i.e., ≤1-in-100-year likelihood of occurrence). Productivity losses after four consecutive years of extreme drought increased by ~2.5-fold compared with those of the first year. These results portend a foundational shift in ecosystem behavior if drought duration and intensity increase, from maintenance of reduced functioning over time to progressive and profound losses of productivity when droughts are extreme.

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Abstract

A number of modelling frameworks exist to estimate resilience from ecological datasets. A subset of these frameworks seeks to estimate the whole ‘stability landscape', which can be used to calculate resilience and identify stable states and tipping points. These methods provide opportunities for insights into possible causes and consequences of variation in ecosystem resilience and dynamics. However, because such models can be complex to implement, there has so far been a substantial barrier to their application in ecological research. Here, we present the ‘mixglm' package for R software, which parametrizes stability landscapes using a mixture model approach. It provides tools for the calculation of resilience, identification of stable states and tipping points, as well as visualization functions. Flexible model specification allows the mean, precision, and probability of each mixture component to be linked to multiple predictors, such as environmental covariates. ‘mixglm' is based on Bayesian inference via NIMBLE and supports normal, beta, gamma, and negative binomial distributed response variables. We illustrate the use of ‘mixglm' with a published case of tree cover in South America, which reports a stability landscape with distinct stable states. Using ‘mixglm', we replicated the identification of these states. Moreover, we quantified the uncertainty of our estimates, and computed resilience estimates of South America's forests. We also conducted a power analysis to provide guidance regarding required sample sizes. ‘mixglm' can be readily used to describe stability landscapes and identify stable states in most spatial datasets, and it is accompanied by tools for the calculation of resilience estimates.

Abstract

Sammendrag på norsk I Norge beiter kjøttfe i store områder av boreal produksjonsskog preget av flatehogst på sommeren (mai-september). Vi studerte først mat- og habitatvalg av disse kyrne (Artikkel I– II), og deretter effektene av storfe på flora og fauna (Artikkel III-V). Datainnsamlingen foregikk i Sørost-Norge i 2015-2017 (Furnes/Vang og Stange/Romedal) og 2021-2023 (Steinvik og Deset). Vi studerte kyrnes ressursvalg ved å klassifisere deres adferd ved hjelp av GPS og akselerasjonsdata, ved å hente inn (fra kart) og måle (i felt) habitatvariabler, ved å samle inn møkkprøver til mikrohistologiske analyser og ved å modellere ressursseleksjonsfunksjoner. Vi fokuserte på unge granplantefelt for å studere effektene av kjøttfe på flora og fauna, siden kyrene selekterer for denne skogstypen. Dessuten har små grantrær høy økonomisk verdi og unge granplantefelt er rikere i blomster og pollinatorer enn det resterende skoglandskapet. På 24 unge granplantefelt satt vi opp parede prøveflater (20x20 m hver), hvorav en omgitt av et gjerde. Vi så på unge trær, vegetasjonen i feltsjiktet og blomsterbesøkende insekter. Siden halvparten av disse granplantefeltene lå innenfor, og den andre halvparten utenfor beiteområdene, kunne vi skille effektene av storfe fra effektene av hjortedyr, som lever vilt i disse skogene. Interaksjoner mellom storfe og hjortedyr studerte vi ved å sette opp viltkamera på de samme granplantefelt og ved å gjennomføre møkktellinger langs et rutemønster i ett av beiteområdene. Kyrne hadde en gressrik diett og selekterte for gressrike habitater, både på stor og på liten skala (Artikkel I). Storfe selekterte for forskjellige habitatvariabler (liten skala) avhengig av adferden: Når de beitet, selekterte de for gressrikt habitat, og når de hvilte, selekterte de for gressrikt habitat med lite helling og høy kronedekning (Artikkel II). Storfe førte til bittelitt høyere dødelighet av unge grantrær, men ikke til høyere risiko for tråkk- og beiteskader (Artikkel III). Storfe fjernet vegetasjon som konkurrerte med unge grantrær, det vil si unge løvtrær og vegetasjon i feltsjiktet (Artikkel III). Storfe påvirket plante-pollinatorsamfunnet på en annen måte enn hjortevilt: Utgjerding av klovdyr utenfor beiteområde (hjortedyr) førte til lavere abundans av blomster, mens utgjerding av klovdyr innenfor beiteområde (hjortedyr og storfe) førte til lavere abundans av blomster og lavere abundans av blomsterbesøkende insekter (Artikkel IV). Elg brukte andre habitattyper enn storfe (Artikkel V). Elgen sitt bruk av unge granplantefelt avtok med økende bruk av storfe (Artikkel V). Mulige beiteinnskrenkende tiltak, samt bevaring av artsmangfoldet i boreal produksjonsskog ble drøftet, og anbefalinger for videre forskning ble gitt.

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Abstract

VKM has assessed the potential risk to Norwegian biodiversity associated with the import of the Turkestan cockroach, Periplaneta lateralis, as live food for hobby animals. Populations of the cockroach are nearly always found in or near buildings, and non-native populations have never been observed in natural environments. No previous observations of P. lateralis have been reported for Norway and it is very unlikely the species will be able to establish and spread into Norwegian nature due to the low winter temperatures and short summers. Furthermore, VKM find that there is low risk associated with the potential effects on biodiversity, if it against all odds, were to establish in Norway. Therefore, VKM concludes that there is low risk associated with import and keeping of P. lateralis in relation to its potential negative effect on Norwegian biodiversity.

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Abstract

The Joint Nature Conservation Committee (UK) launched the Air Pollution Recovery Indicators Programme (APRI) in 2023. Royal Botanic Gardens Kew’s APRI experimental work focuses on heathland recovery where nitrogen (N) pollution has significantly impacted ecosystem services, including carbon sequestration and biodiversity. Despite the important ecosystem services they provide, little is known about how heathlands might recover from N pollution, especially below ground. We are investigating the potential of ericoid mycorrhizal (ErM) fungi, in both soil and roots, as novel indicators of recovery from N pollution in southern England, and comparing these results to soil and heather roots sourced in less polluted Norway heathlands. ErM fungi form symbiotic associations with heather roots and liverwort rhizoids, mining organic N and phosphorus from nutrient-poor heathland soils; in exchange, the plants supply carbon to the fungi. As such there is an expectation that ErM fungi will respond rapidly to changes in N pollution. Our field experiments are also assessing changes in lichen community composition and evaluating the practicality of using LiDAR, RGB and multispectral drone technology to measure and link biomass changes above ground to N fertilization. We have the following research questions regarding above and below ground heathland condition: How are ErM and soil fungal communities impacted by, and how do they recover from, N pollution? How do changes in above ground vegetation (plants, lichens) link with ErM and soil fungal communities? What are the ErM and non-mycorrhizal fungal communities across a N pollution gradient, in southern England and coastal Norway?