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.
2023
Forfattere
Sandra Rojas-Botero Simon Dietzel Johannes Kollmann Leonardo H. TeixeiraSammendrag
Urbanization causes ecosystem degradation and losses of biodiversity. Still, urban landscapes favor organisms, depending on how well they fit the anthropogenic conditions. Creating urban green spaces of high ecological quality, such as pollinator-friendly road verges, promotes biodiversity in cities. We sowed a seed mixture consisting of 26 native plant species with diverse functional traits in 46 road verge patches along four urban roads in Munich (South Germany) in 2019/20 and monitored in 2020/21. Control were pre-existing turfgrass patches with conventional management. We assessed species richness, Shannon diversity, and Pielou's evenness, whereas functional composition was evaluated via functional richness, evenness, and divergence, based on 13 plant traits. To study urbanization effects on species and functional composition, we analyzed soil characteristics and tree shading at the local level, as well as distance to city center, imperviousness, and edge density at the landscape level. We used linear models and ordination analysis to assess treatment, local and landscape effects, and the influence of planting year on taxonomic and functional composition. Rehabilitation treatment explained most differences in species and functional composition. Species richness was lower in the city center and at sites with high soil organic matter; Pielou's evenness increased with soil pH. Trait composition differed between rehabilitated and control patches, and varied according to planting year. Soil bulk density negatively affected functional richness for all traits combined, and edge density reduced functional evenness of establishment traits. We conclude that urban filtering, in combination with planting year, shapes species and trait composition of rehabilitated road verges. Hence, local and landscape-level trait–environment interactions affect the assembly of road verge grasslands. Finally, our findings suggest that establishment traits have a pivotal role in the development of rehabilitated road verges, while the predictability of rehabilitation outcomes may be hindered even when seeding specifically designed seed mixtures.
Forfattere
Binbin Xiang Torben Peters Theodora Kontogianni Frawa Vetterli Stefano Puliti Rasmus Astrup Konrad SchindlerSammendrag
Panoptic segmentation is the combination of semantic and instance segmentation: assign the points in a 3D point cloud to semantic categories and partition them into distinct object instances. It has many obvious applications for outdoor scene understanding, from city mapping to forest management. Existing methods struggle to segment nearby instances of the same semantic category, like adjacent pieces of street furniture or neighbouring trees, which limits their usability for inventory- or management-type applications that rely on object instances. This study explores the steps of the panoptic segmentation pipeline concerned with clustering points into object instances, with the goal to alleviate that bottleneck. We find that a carefully designed clustering strategy, which leverages multiple types of learned point embeddings, significantly improves instance segmentation. Experiments on the NPM3D urban mobile mapping dataset and the FOR-instance forest dataset demonstrate the effectiveness and versatility of the proposed strategy.
Forfattere
Albert Kjartan Dagbjartarson Imsland Patrick Reynolds Lauri Teemu Kapari Simo Maduna Snorre Hagen Anna Hanssen Ólöf Dóra Bartels JónsdóttirSammendrag
The aim of this study was to evaluate whether sea lice grazing efficiency, behaviour, size variation and cataract development can be improved through selective breeding of lumpfish. A series of studies was conducted over a four-year period where distinctive lumpfish families were established initially from wild caught mature fish and latterly from established breeding lines. Four subsequent trials (called: Phase I-IV) with ten families of lumpfish (N = 480) with a mean (± SD) weight of 46.4 ± 9.4 g (Phase I), 54.8 ± 9.2 g (Phase II), 42.0 ± 7.4 g (Phase III) and 31.3 ± 2.4 g (Phase IV) were distributed among ten sea cages (5 × 5 × 5 m) during autumn 2018 to spring 2022, each stocked with 400–404 Atlantic salmon with an average initial mean (± SD) of 387 ± 9 g (Phase I), 621 ± 15 g (Phase II), 280 ± 16 g (Phase III) and 480 ± 66 g (Phase IV). All the ten cages were stocked with 48 lumpfish (12% stocking density). In all phases there was a large inter-family variation of lice grazing of lumpfish of both L. salmonis and C. elongatus. When sea lice grazing was scaled in relation to sea lice infestation numbers on the salmon the highest sea lice grazing activity was found in Phase IV and in particular in families sired from farmed parents. There was a general trend for mean start weights and standard deviations to decrease as the phases continued. A significant increase was found in frequency of behaviour associated with feeding on natural food sources and grazing sea lice from salmon during each subsequent phase. The increase in incidence of cataracts from start to end of each trial phase was significantly reduced from Phase I (16%) to Phase IV (2%). Overall, present findings showed that sea lice grazing of both L. salmonis and C. elongatus, size variation, cataract prevalence and behaviour types can be enhanced through selection and targeted breeding programs.
Forfattere
Jian Liu Faruk Djodjic Barbro Ulen Helena Aronsson Robert Barneveld Marianne Bechmann Lars Bergström Tore Krogstad Sigrun Hjalmarsdottir Kværnø Katarina Kyllmar Anne Falk Øgaard Lillian Øygarden Eva SkarbøvikSammendrag
Det er ikke registrert sammendrag
Forfattere
Vicente Guallart Michael Salka Daniel Ibañez Fabio Salbitano Silvano Fares Arne Sæbø Stefano Boeri Livia Shamir Lucrezia De Marco Sofia Paoli Maria Chiara Pastore Jerylee Wilkes-Allemann Evelyn Coleman Brantschen Ivana ŽivojinovićSammendrag
This introductory chapter will evaluate how we have reached the current point in the history of world urbanity, its relationship with nature, and why a fusion between the two is now necessary. In order to define BioCities as cities which follow the principles of natural ecosystems to promote life, we will refer to the extensive knowledge of the history of urban science, the need for cities to be reinvented based on ecological principles, and new methods of analysing and measuring reality through digital systems. This vision of the main functions and traits of BioCities will also serve as a thread and reference for the subsequent chapters which will highlight and elaborate on the different properties of the BioCity vision. The final chapter will draw from this vision the constituting principles of the BioCity and will outline possible pathways of transition towards BioCities.
Forfattere
El Houssein Chouaib HarikSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Forfattere
El Houssein Chouaib HarikSammendrag
In this paper, we investigated the idea of including mobile robots as complementary machinery to tractors in an agricultural context. The main idea is not to replace the human farmer, but to augment his/her capabilities by deploying mobile robots as assistants in field operations. The scheme is based on a leader–follower approach. The manned tractor is used as a leader, which will be taken as a reference point for a follower. The follower then takes the position of the leader as a target, and follows it in an autonomous manner. This will allow the farmer to multiply the working width by the number of mobile robots deployed during field operations. In this paper, we present a detailed description of the system, the theoretical aspect that allows the robot to autonomously follow the tractor, in addition to the different experimental steps that allowed us to test the system in the field to assess the robustness of the proposed scheme.
Sammendrag
The use of cover crops in cereal production as a climate smart agricultural practice is generally used to increase carbon sequestration in soils. However, increased plant biomass in wintertime can trigger N2O emissions due to decay during freeze-thaw cycles. So far little is known about N2O winter emissions from cover crops which, in the worst case, could cancel out the carbon gain by cover crops. Here we report N2O emissions from a two-year field experiment in SE Norway with barley and various cover crops (perennial and Italian ryegrass, oilseed radish, summer and winter vetch, phacelia and a mixture of different herbs) measured against controls without cover crops. A field robot was used for measuring N2O emissions at high temporal resolution during off-season, i.e., the period from cereal crop harvest to cereal crop sowing. During the first winter, the snow cover was poor and the significantly higher N2O emissions were measured from oilseed radish during spring thaw whereas perennial ryegrass reduced emissions. A second winter is measured and N2O emissions from both years will be presented. In addition, continuous measurements are needed to assess the effect of diurnal freeze-thaw cycles on N2O emissions before scaling up to annual N2O emission fluxes and comparing with C sequestration.
Forfattere
Shelemia Nyamuryekung'e Andrew Cox Andres Perea Richard Estell Andres F. Cibils John P. Holland Tony Waterhouse Glenn Duff Micah Funk Skye Aney Matthew M. McIntosh Sheri Spiegal Brandon Bestelmeyer Santiago A. UtsumiSammendrag
Virtual fencing (VF) is an alternative method to control livestock dispersal. This method consists of the use of animal wearable collars that employ auditory-electric pulse cues to deter animals from exiting their predefined containment zones. The study aimed to document skin defense (SkinM) and association learning mechanism (AssocM) in describing the conditioning behavior of the VF application. Nursing Brangus cows at the New Mexico State University’s Chihuahuan Desert Rangeland Research Center were allotted three days of free access to feeding areas (0.19ha) with VF-deactivated (VF-Off) or VF-Activated (VF-On) collars restricting one-third of the penned area. This training sequence was repeated twice (6-day/Period) with two replications (n=11 and 17cows). The VF collars communicated real-time animal positions at 15-minute intervals. ANOVA was used to compare daily-derived variables per cattle on the percentage of time spent within the containment and restricted zones (SkinM) and the number of auditory and electric pulses emitted during the VF-On configurations (AssocM). The VF-On treatment increased the percentage of time collared animals spent within the containment zone (98.4 vs.72.0 ±1.0 %Time;P<0.01) and reduced the percentage of time within the restricted zone (1.6 vs.28.0 ±1.0 %Time;P<0.01) compared to the VF-Off treatment. Exposure to VF-On in Period 1 triggered a greater frequency of auditory (1.8 vs.0.6 ±0.4;P<0.01) and electrical pulses (0.7 vs.0.2 ±0.2;P<0.01) than in Period 2. Results indicate that groups of cows learn rapidly to respond to VF boundaries by reducing the time spent within the restricted areas (SkinM) and relying increasingly on auditory cues to alter behavior (AssocM).