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.
2017
Abstract
Research concerning the cultural practice of golf course fairways is important because legislation on pesticide reduction in Europe and North America may potentially cause serious weed problems. Establishing a strong, competitive turfgrass sward may aid in reducing the invasion of broadleaved weeds and Poa annua L. The objective of this research was to determine changes in the grass species composition and weed occurrence of in-use fairway turfs after repeated overseeding of three grass species separately: Lolium perenne L., Festuca rubra L., and Poa pratensis L., all at rates 300 kg ha−1. Overseeding was conducted with a disc seeder, alone or in combination with extra fertilizer (50 kg N + 34 kg P ha−1) in either May or September on three Danish golf courses from 2011 to 2013. Results showed no increase in the population of F. rubra or P. pratensis after 3 yr of overseeding. Lolium perenne was successfully introduced when seeded in autumn and when extra fertilizer was added immediately after overseeding. None of the overseeding treatments reduced the occurrence of P. annua, Taraxacum officinale F.H. Wigg., Bellis perennis L., or Trifolium repens L. The results are discussed in relation to the fact that the fairways were unirrigated and that they were open to play after overseeding.
Authors
Ilona Kása Györgyi Gelybó Ágota Horel Zsòfia Bakacsi Eszter Tóth Sándor Koós Márton Dencső Johannes Deelstra Sándor Molnár Csilla FarkasAbstract
Catchment scale hydrological models are promising tools for simulating the effect of catchment-specific processes and management on soil and water resources. Here, we present a model intercomparison study of runoff simulations using three different semi-distributed rainfall-runoff catchment models. The objective of this study was to demonstrate the applicability of the Hydrologiska Byrans Vattenavdelning (HBV-Light); Precipitation, Evapotranspiration and Runoff Simulator for Solute Transport (PERSiST); and INtegrated CAtchment (INCA) models on Somogybabod Catchment, near Lake Balaton, Hungary. The models were calibrated and validated against observed discharge data at the outlet of the catchment for the period of January 1, 2006 –July 12, 2015. Model performance was evaluated using graphical representations, e.g. daily and monthly hydrographs and Flow Duration Curves (FDC) and model evaluation statistic; Nash–Sutcliffe efficiency (NSE) and coefficient of determination (R2). The simulation results showed that the models provided good estimates of monthly average discharge (0.60–0.90 NSE; 0.60–0.91 R2) and satisfactory results for daily discharge (0.46–0.62 NSE; 0.50–0.67 R2). We found that the application of hydrological models serves as a powerful basis for ensemble modelling of average runoff and could enhance our understanding of the eco-hydrological and transport processes within catchments. On the other hand, it can highlight the uncertainty of model forecasts and the importance of goal specific evaluation.
Abstract
No abstract has been registered
Authors
Tore SkrøppaAbstract
No abstract has been registered
Authors
Umberto Salvagnin M. Malnoy Gunda Thöming M. Tasin S. Carlin S. Martens U. Vrhovsek S. Angeli G. AnforaAbstract
In nature plant terpenoids play multiple ecological roles. Many phytophagous insects use them as kairomones to locate their host plants. This is also the case for Lobesia botrana, which is the main pest of European vineyards. It was found that a specific blend of the terpenoids (E)-β-caryophyllene, (E)-β-farnesene and the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene emitted by grapevine was attractive to L. botrana females, and the attractiveness was shown to be dependent on the kairomone ratio. In this work, we generated stable grapevine transgenic lines with altered (E)-β-caryophyllene and (E)-β-farnesene emission compared to natural plants. Thus, we modified the ratio between these two kairomones in vivo, and tested how it affected L. botrana behaviour.
Abstract
Plant defence against environmental stressors often changes dramatically as plant develop. The composition of secondary compounds (PSM) in the vegetation of a landscape has extensive influence on ecosystem functioning. It is therefore crucial that we understand how various temporal factors affect plant content of PSMs, particularly those indirectly induced and controlled by human activity. One illustrative PSM group of major ecological interest is phenolics, which serve needs as diverse as herbivory defence, pathogen resistance, allelopathy or symbioses signalling, frost and drought hardiness, and photodamage protection. I will present results from our ongoing studies of defensive chemistry of European beech (Fagus sylvatica) and birch (Betula spp) across seasons and ages, and discuss the results in relation to ecological theories and functionality of plant chemical defence.
Authors
Ola FlatenAbstract
Western livestock sectors have shifted towards fewer, larger farms, causing concerns about the appearance of the countryside, ecosystem services, and rural depopulation. This study empirically estimates factors likely to affect exit intentions in sheep farms. Data were collected from specialised sheep farms included in the Norwegian Farm Business Survey. Of the 59 responses, 44 operators believed the farm would be producing sheep in 10 years. A logistic regression model was used to determine the most decisive variables associated with an exit intention, where the interdependence of factors affecting profitability and, subsequently, exit intention were taken into account. This study found that farmers reporting the most positive views of the local farming community were less likely to plan an exit. Exit intentions were not significantly influenced by farming goals, location, off-farm income, or profitability. The primacy of non-economic, community-based factors as an engine to sustain farms, suggests that more attention need to be paid to social processes and relations in local communities. Farmer groups and policy-makers should consider how to encourage supportive local communities when designing policies to retain sheep farms.
Authors
Eldrid Lein MoltebergAbstract
No abstract has been registered
Authors
Signe Nybø Per Arneberg Erik Framstad Rolf Anker Ims Anders Lyngstad Ann Kristin Schartau Hanne Sickel Anne Sverdrup-Thygeson Vigdis VandvikAbstract
Dette kapittelet presenterer forslaget til fagsystem for vurdering av god økologisk tilstand og begrunner valgene som er tatt. Deltagere i undergruppe hav (Per Fauchald, Normann Whitaker Green, Eva Ramirez-Llodra, Sylvia Frantzen, Cecilie von Quillfeldt og Anne Kirstine Frie) har bidratt betydelig til å utvikle egenskapene som gir en normativ beskrivelse av god økologisk tilstand i kapittel 3.4 .
Authors
Alexander Kopatz Rune Andreassen Daniel Kling Rolf Randa Kristin Forfang Snorre Hagen Hans Geir EikenAbstract
We reconstructed family relationships, parent-child and siblings, among the brown bear (Ursus arctos) sampled in Sør-Varanger, Norway. Basis of this study are observed family relationships by the wildlife management. We compared this strong indication of relatedness with testing particular family relationships using SNP- and STR-genotype data of 154 brown bears sampled mainly non-invasively in the area from 2004 to 2016. We calculated likelihood ratios (LRs) and reconstructed family groups with the program FAMILIAS, which was used to reconstruct family relationships in human forensics. When the LR of each relationship, parent-child or siblings, was tested, 40 (38.1%) relationships were confirmed based solely on genetic data. The allele sharing analysis visualized as dendrograms supported that a large proportion of the remaining observed cases that were not confirmed as parent-child or siblings did share a closer family relationship. More detailed analysis is necessary to deduce the nature of these relationships (cousins, uncle-nephew etc.). Based on the genetic data we found, that the minimum number of cubs per year was on average 4.08. The applied SNP-chip has been developed on the Swedish brown bear population, a population different to the bears living in Sør-Varanger. The performance of the SNP-chip in this study rises questions of its applicability for family analysis in other brown bear populations and shows the need for further evaluation of the individual loci on the chip. Nevertheless, the combined SNP-data from all loci seems to provide power enough to detect the previously reported subpopulation structure. The observational data, sampling effort and quality of the sample material of the brown bears in Sør-Varanger is remarkable and the material provides an excellent testing ground to validate and improve the SNP-chip to reconstruct family groups.