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.
2018
Abstract
Blue and yellow sticky traps equipped with blue light emitting diodes (LEDs) were evaluated for their attractiveness to the western flower thrips (Frankliniella occidentalis Pergande) and compared to similar traps without light in two greenhouses with commercial production of either mixed herbs or Alstroemeria cut flowers. Blue traps were more attractive to F. occidentalis than the yellow traps in both crops, regardless of whether they were equipped with light or not. In herbs, the blue light equipped traps caught 1.7 to 2.5 times more thrips compared to blue traps without light, and 1.7 to 3.0 times more thrips than yellow traps with light. Blue light on both blue and yellow traps increased thrips catches in one out of two experiments in Alstroemeria. The blue light equipped traps caught 3.4 and 4.0 times more thrips than blue traps without light in coloured and white Alstroemeria cultivars, respectively, whereas yellow light equipped traps increased thrips catches 4.5 times compared to yellow traps without light in both coloured and white cultivars. The yellow light equipped traps caught, however, only equal to or only slightly more thrips than blue traps without light, and caught fewer thrips than the light equipped blue traps. The relative trapping efficiency of the different combinations of trap colour and light varied with experiment, crop and Alstroemeria cultivars. This suggests that factors other than merely the addition of light influenced the thrips' phototactic response to the traps. Such factors could be differences in the relative strength of the competition between attractive signals from traps and plants between the two crops and Alstroemeria cultivars, thrips density, seasonal lighting conditions or different pest management strategies and other operational procedures in the greenhouses. The light from the traps did not increase the thrips population on the plants below the traps. The implications of the results for thrips control and suggestions for further studies are discussed.
Abstract
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Abstract
Det er ikke registrert sammendrag
Authors
Antonio Carlos Ferraz Filho Blas Mola-Yudego José Ramón González-Olabarria José Roberto Soares ScolforoAbstract
This study focuses on the effects of different thinning regimes on clonal Eucalyptus plantations growth. Four different trials, planted in 1999 and located in Bahia and Espírito Santo States, were used. Aside from thinning, initial planting density, and post thinning fertilization application were also evaluated. Before canopy closure, and therefore before excessive competition between trees took place, it was found that stands planted under low densities (667 trees per hectare) presented a lower mortality proportion when compared to stand planted under higher densities (1111 trees per hectare). However, diameter growth prior to thinning operations was not statistically different between these two densities, presenting an overall mean of 4.9 cm/year. After canopy closure and the application of the thinning treatments, it was found that thinning regimes beginning early in the life of the stand and leaving a low number of residual trees presented the highest diameter and height growth. Unthinned treatments and thinning regimes late in the life of the stand (after 5.5 years), leaving a large number of residual trees presented the highest values of basal area production. The choice of the best thinning regime for Eucalyptus clonal material will vary according to the plantation objective.
Abstract
Det er ikke registrert sammendrag
Abstract
Norway is strongly committed to the Paris Climate Agreement with an ambitious goal of 40% reduction in greenhouse gas emission by 2030. The land sector, including agriculture and forestry, must critically contribute to this national target. Beyond emission reduction, the land sector has the unique capacity to actively removing CO2 from the atmosphere through biological carbon storage in biomass and in soils. Soils are the largest reservoir of terrestrial carbon, and relatively small changes in soil carbon content can have an amplified mitigation effect on the Earth’s climate. Therefore, improved management of soils for carbon storage is receiving a lot of attention, for example through international political initiatives such as the “4-permill” initiative. However, in Norway, many mitigation measures targeting soil carbon might negatively impact food production and economic activity. For example, soil carbon storage can be increased by shifting from cereal crop production to grasslands, but Norway already has abundant grassland and a comparatively small area dedicated to cereals. Another such issue is cultivation on drained peatland, where food is produced at the expense of large losses of soil carbon as CO2 to the atmosphere. Therefore, there is a need to look for win-win solutions for soil carbon storage, which benefit both food production and climate mitigation. Large-scale conversion of agricultural and forest waste biomass to biochar is such an option, and is considered the activity with the largest potential for soil carbon sequestration in Norway. Biochar has been demonstrated to have a mean residence time exceeding 100 years in Norwegian field conditions (Rasse et al, 2017), and no negative effects on plant and soils has been observed. However, despite the convincing benefits of biochar as a climate mitigation solution, it has not yet advanced much beyond the research stage, notably because its effect on yield are too modest. Here, we will first present the comparative advantage of biochar technology as compared to traditional agronomy methods for large-scale C storage in Norwegian agricultural soils. We will further discuss the need for developing innovations in pyrolysis and nutrient-rich waste recycling leading to biochar-fertilizer products as win-win solution for carbon storage and food production.
Authors
Roland Bol Gerard Gruau Per-Erik Mellander Rémi Dupas Marianne Bechmann Eva Skarbøvik Magdalena Bieroza Faruk Djodjic Miriam Glendell Philip Jordan Bas van der Grift Michael Rode Erik Smolders Mieke Verbeeck Sen Gu Erwin Klumpp Ina Pohle Maelle Fresne Chantal Gascuel-OdouxAbstract
In this paper, we outline several recent insights for the priorities and challenges for future research for reducing phosphorus (P) based water eutrophication in the agricultural landscapes of Northwest Europe.We highlight that new research efforts best be focused on headwater catchments as they are a key influence on the initial chemistry of the larger river catchments, and here many management interventions are most effectively made. We emphasize the lack of understanding on how climate change will impact on P losses from agricultural landscapes. Particularly, the capability to disentangle current and future trends in P fluxes, due to climate change itself, from climate driven changes in agricultural management practices and P inputs. Knowing that, future climatic change trajectories for Western Europe will accelerate the release of the most bioavailable soil P. We stress the ambiguities created by the large varieties of sources and storage/transfer processes involved in P emissions in landscapes and the need to develop specific data treatment methods or tracers able to circumvent them, thereby helping catchment managers to identify the ultimate P sources that most contribute to diffuse P emissions. We point out that soil and aqueous P exist not only in various chemical forms, but also in range of less considered physical forms e.g., dissolved, nanoparticulate, colloidal and other particulates, all affected differently by climate as well as other environmental factors, and require bespoke mitigation measures. We support increased high resolution monitoring of headwater catchments, to not only help verify the effectiveness of catchments mitigation strategies, but also add data to further develop new water quality models (e.g., those include Fe-P interactions) which can deal with climate and land use change effects within an uncertainty framework. We finally conclude that there is a crucial need for more integrative research efforts to deal with our incomplete understanding of the mechanisms and processes associated with the identification of critical source areas, P mobilization, delivery and biogeochemical processing, as otherwise even highintensity and high-resolution research efforts will only reveal an incomplete picture of the full global impact of the terrestrial derived P on downstream aquatic and marine ecosystems.
Authors
O. Janne Kjønaas Sunil Mundra Teresa Gómez de la Bárcena Mette Hansen Gro Hylen Håvard KauserudAbstract
Tree species change has been suggested as one of the government policies to mitigate climate change in Nor-way with the aim to increase the annual uptake of CO2 and the long-term storage of carbon (C) in forests. The strategy includes replacing native, deciduous species with fast-growing species, mainly Norway spruce. A shift in tree species is expected to affect the pools and fluxes of C in the stand as well as the microbial community. As part of the BalanC project, we assess C storage related to shift in tree species cover in western Norway and whether a corresponding shift in soil microbial communities are happening. The study aim at integrating results on soil respiration, C mineralization, soil stability, diversity of bacteria, fungi and micro-eukaryotes, soil nutrient pools, litter inputs and edaphic factors at the stand level in order to identify key drivers for changes in the soil C stocks. Fifteen paired plots of native birch and planted Norway spruce at five locations were sampled. Prelimi-nary results suggests a redistribution of C from the mineral soil to the forest floor in the spruce stands, with minor changes in the total soil C pools over the 45-60 years since the tree species change. The in situ soil respi-ration and heterothropic respiration, as well as C mineralization rates, were higher in birch than in spruce stands. Differences in C mineralization rates attenuate with depth between forest types. The microbial com-munities of the three organismal groups were all strongly structured along the vertical depth.
Authors
Solveig Marie Stubsjøen Kristin Sørheim Matteo Chincarini Jon Bohlin Emma Brunberg Boris Fuchs Rupert Palme Lise GrøvaAbstract
Tick-borne fever (TBF), caused by the bacterium Anaplasma phagocytophilum and transmitted by the tick Ixodes ricinus, has considerable consequences for animal welfare and economy in the sheep industry. Non-invasive, objective methods to quantify chronic stress are needed in order to evaluate the welfare impact of disease. The aim of this study was 1) to evaluate hair cortisol (HC) and hair cortisone (HCn) as biomarkers of chronic stress in sheep with TBF and 2) to test whether there was an association between the development of TBF and con- centrations of HC, HCn and faecal cortisol metabolites (FCM) and body weight. The experiment took place in an area with a high prevalence of TBF, and thirty lambs were used in the study. Wool samples were collected in Week 0, in Week 3 (before turn out on homeland spring pasture), in Week 6 (before turn out on summer rangeland pasture) and at the end of the summer (Week 15). Faecal samples were collected every week (ie. Week 0–6 and Week 15). Symptoms of TBF developed in 15 lambs, of which all recovered from the disease after treatment with antibiotics. HC levels decreased progressively, and significantly, between Week 0, 3, 6 and 15 (p < 0.001), while HCn only decreased from Week 0 to Week 3 (p < 0.001) and then remained stable between Week 3–15. FCM increased between Week 0 and 5 (p = 0.027), and a significant association was found between increased FCM levels in Week 5 and lambs developing clinical signs of TBF (p = 0.022). We also found an association between lambs developing clinical signs of TBF and elevated HCn levels in Week 6 (p = 0.013). A slightly lower weight gain at later time points (Week 6 and 15) were found in the affected lambs compared to clinically healthy lambs. Our results indicate local production and/or metabolism of glucocorticoids in the hair follicles. This study strengthens our previous finding of a potential merit of hair cortisone as a biomarker of chronic stress in sheep.
Authors
Liv Østrem Torben Asp Marc Ghesquière Yoshinori Sanada Odd Arne RognliAbstract
Norwegian cultivars and breeding materials of perennial ryegrass and Festulolium were planted at three locations in Denmark, France and Japan for test-ing of resistance against leaf diseases. In general, all plant materials were susceptible to crown rust. The highest incidence of rust attack occurred at the French site, which due to its climatic conditions might be the most suitable testing site for future scoring of similar plant material. Entries based on introgressed genetic materials from UK were most resistant towards crown rust. Crown rust resistance needs increased focus as a breeding objective in the Nordic region due to climate changes, which will most likely lead to increased infection of leaf diseases.