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.
2017
Abstract
Det er ikke registrert sammendrag
Authors
Florencia A. Yannelli Christiane Koch Jonathan M. Jeschke Johannes KollmannAbstract
Several hypotheses have been proposed to explain biotic resistance of a recipient plant community based on reduced niche opportunities for invasive alien plant species. The limiting similarity hypothesis predicts that invasive species are less likely to establish in communities of species holding similar functional traits. Likewise, Darwin’s naturalization hypothesis states that invasive species closely related to the native community would be less successful. We tested both using the invasive alien Ambrosia artemisiifolia L. and Solidago gigantea Aiton, and grassland species used for ecological restoration in central Europe. We classified all plant species into groups based on functional traits obtained from trait databases and calculated the phylogenetic distance among them. In a greenhouse experiment, we submitted the two invasive species at two propagule pressures to competition with communities of ten native species from the same functional group. In another experiment, they were submitted to pairwise competition with native species selected from each functional group. At the community level, highest suppression for both invasive species was observed at low propagule pressure and not explained by similarity in functional traits. Moreover, suppression decreased asymptotically with increasing phylogenetic distance to species of the native community. When submitted to pairwise competition, suppression for both invasive species was also better explained by phylogenetic distance. Overall, our results support Darwin’s naturalization hypothesis but not the limiting similarity hypothesis based on the selected traits. Biotic resistance of native communities against invasive species at an early stage of establishment is enhanced by competitive traits and phylogenetic relatedness.
Authors
Bjørn Egil FløAbstract
Det er ikke registrert sammendrag
Authors
Bjørn Egil FløAbstract
Det er ikke registrert sammendrag
Abstract
Det er ikke registrert sammendrag
Authors
Vlada Vitunskienė Vilija Aleknevičienė Astrida Miceikienė Jonas Čaplikas Vaclovas Miškinis Irina Pilvere Daiva Makutėnienė Vida Dabkienė Vidas Lekavičius Knut Øistad Neringa Ramanauskė Virginija Kargytė Darius Jazepčikas Evaldas Serva Aurelija MarkelytėAbstract
Det er ikke registrert sammendrag
Abstract
Det er ikke registrert sammendrag
Abstract
To degrade lignocellulose efficiently, lower termites rely on their digestive tract’s specific features (i.e., hysiological properties and enzymes) and on the network of symbiotic fauna harboured in their hindgut. This complex ecosystem, has different levels of symbiosis, and is a result of diverse co-evolutionary events and the singular social behaviour of termites. The partnership between termites and flagellate protists, together with prokaryotes, has been very successful because of their co-adaptative ability and efficacy in resolving the needs of the involved organisms: this tripartite symbiosis may have reached a physiologically stable, though dynamic, evolutionary equilibrium. The diversity of flagellate protists fauna associated with lower termites could be explained by a division of labour to accomplish the intricate process of lignocellulose digestion, and the ability to disrupt this function has potential use for termite control. Multi-level symbiosis strategy processes, or the cellulolytic capacity of flagellate protists, may lead to innovative pathways for other research areas with potential spin-offs for industrial and commercial use.
Authors
Ola Stedje HanserudAbstract
Det er ikke registrert sammendrag
Authors
Eveliina Kallioniemi Jens Åström Graciela Rusch Sondre Dahle Sandra Charlotte Helene Åström Jan Ove GjershaugAbstract
There is consensus that land-use change is a main driver behind the recent declines of many pollinator populations in Europe. However, it is still not adequately understood how the local resource quality and landscape composition influence pollinators, and if and how the effects vary in space and time. We analysed the influence of landscape- (2 km radius) and local scale- (50 m transects) resources on bumblebee species richness and abundance during two years in South-eastern Norway, where agriculture is highly modernised but landscapes still show limited spatial homogenization. Local flower density and species richness were strongly positively associated with bumblebee densities and species richness, but higher landscape-level flower species richness were linked to lower local bumblebee abundances. Early and late mass flowering crops had clear, but contrasting, effects. The total area of early flowering crops had a consistent negative impact on bumblebee density and species richness throughout the season, while late flowering crops had a positive impact in the beginning of the season before their bloom, suggesting a carry-over effect from previous years. The negative effects of early flowering crops could be due to competition of bumblebees with honey-bees, which are widely used in these crops. Bumblebee density and species richness were clearly negatively correlated with the total area of forest and flower-poor land use areas, including grass fields and cereals. In contrast, bumblebees were positively associated with most linear elements in the landscape (especially pasture and cropland verges), except for roads, which negatively affected bumblebee densities, possibly due to increased mortality, since the quality of the flower resources did not differ from other linear elements. Our results show that the quality and the spatial and temporal distribution of flower resources within the landscape are important drivers for bumblebees, but can create counterintuitive distribution patterns depending on the temporal and spatial resolution of the survey. Increasing flower resources in linear elements and the amount of late mass-flowering crops may be viable management measures to improve conditions for bumblebees in moderately intensified landscapes. Bombus Pollinators Linear features Mass-flowering crops Landscape ecology Agricultural landscapes Ecosystem services