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.
2020
Sammendrag
Etter oppdrag fra Statens vegvesen Region sør og prosjektet E18 Bommestad – Sky har NIBIO utført oppfølging av vannmiljø i Farris og Farriselva. Arbeidene har vært tilknyttet ferdigstilling av lokalveinettet rundt Farriseidet, utfylling mellom akse 5 og 6 ved østre odde samt opptak av midlertidig vannledning i Farriskilen og Farris og til sist opptak av siltgardiner mellom akse 5 og 6. I Farriselva har det foregått arbeid tilknyttet flomsikring med plastring av elvebunn og sider, samt konstruksjon av ny bru over Farriselva ved demning.
Sammendrag
Fractionation of forage legume crops can make a protein-rich feed available for monogastric animals. The aim of the current study was to assess the effect of fractionation method, leaf stripping or juice production, in lucerne (Medicago sativa) on protein yield in low-fibre fractions. We established field trial with replications on two lucerne varieties in Menemen, Turkey, in 2018. At first cut in 2019 whole plant and six different fractions were processed and sampled. Across varieties, juice, leaves and leaf juice yields accounted for 45%, 53% and 24% of the whole plant dry matter yield, respectively. Crude protein content was higher in leaf juice (26%) than whole plant juice (23%) and the content in leaves differed between the varieties (22% and 27%). Leaf stripping separated a higher proportion (on average 70%) of the total crude protein in the plant than juice production (on average 55%). The effects of variety, harvesting time and number of cut need further investigation.
Sammendrag
In the Nordic countries Finland, Norway and Sweden, the most common regeneration method is planting after clearcutting and, often, mechanical site preparation (MSP). The main focus of this study is to review quantitative effects that have been reported for the five main MSP methods in terms of survival and growth of manually planted coniferous seedlings of Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestris L.) and lodgepole pine (Pinus contorta var. latifolia Engelm.) in clearcuts in these three countries. Meta analyses are used to compare the effects of MSP methods to control areas where there was no MSP and identify any relationships with temperature sum and number of years after planting. In addition, the area of disturbed soil surface and the emergence of naturally regenerated seedlings are evaluated. The MSP methods considered are patch scarification, disc trenching, mounding, soil inversion and ploughing. Studies performed at sites with predominately mineral soils (with an organic topsoil no thicker than 0.30 m), in boreal, nemo-boreal and nemoral vegetation zones in the three Fenno-Scandinavian countries are included in the review. Data from 26 experimental and five survey studies in total were compiled and evaluated. The results show that survival rates of planted conifers at sites where seedlings are not strongly affected by pine weevil (Hylobius abietis L.) are generally 80–90% after MSP, and 15–20 percent units higher than after planting in non-prepared sites. The experimental data indicated that soil inversion and potentially ploughing (few studies) give marginally greater rates than the other methods in this respect. The effects of MSP on survival seem to be independent of the temperature sum. Below 800 degree days, however, the reported survival rates are more variable. MSP generally results in trees 10–25% taller 10–15 years after planting compared to no MSP. The strength of the growth effect appears to be inversely related to the temperature sum. The compiled data may assist in the design, evaluation and comparison of possible regeneration chains, i.e. analyses of the efficiency and cost-effectiveness of multiple combinations of reforestation measures.
Forfattere
Steen Magnussen Ronald E. McRoberts Johannes Breidenbach Thomas Nord-Larsen Göran Ståhl Lutz Fehrmann Sebastian SchnellSammendrag
Background: Large area forest inventories often use regular grids (with a single random start) of sample locations to ensure a uniform sampling intensity across the space of the surveyed populations. A design-unbiased estimator of variance does not exist for this design. Oftentimes, a quasi-default estimator applicable to simple random sampling (SRS) is used, even if it carries with it the likely risk of overestimating the variance by a practically important margin. To better exploit the precision of systematic sampling we assess the performance of five estimators of variance, including the quasi default. In this study, simulated systematic sampling was applied to artificial populations with contrasting covariance structures and with or without linear trends. We compared the results obtained with the SRS, Matérn’s, successive difference replication, Ripley’s, and D’Orazio’s variance estimators. Results: The variances obtained with the four alternatives to the SRS estimator of variance were strongly correlated, and in all study settings consistently closer to the target design variance than the estimator for SRS. The latter always produced the greatest overestimation. In populations with a near zero spatial autocorrelation, all estimators, performed equally, and delivered estimates close to the actual design variance. Conclusion: Without a linear trend, the SDR and DOR estimators were best with variance estimates more narrowly distributed around the benchmark; yet in terms of the least average absolute deviation, Matérn’s estimator held a narrow lead. With a strong or moderate linear trend, Matérn’s estimator is choice. In large populations, and a low sampling intensity, the performance of the investigated estimators becomes more similar. Keywords: Spatial autocorrelation, Linear trend, Model based, Design biased, Matérn variance, Successive difference replication variance, Geary contiguity coefficient, Random site effects
Forfattere
Daniel Flø Trond Rafoss Per Hans Micael Wendell Leif SundheimSammendrag
Background The Siberian moth (Dendrolimus sibiricus) is a serious pest of conifers in Russia, Northern Kazakhstan, Mongolia and China. The western border of the pest’s distribution in Russia is disputed, but it is present west of the 60th meridian east. The pest has the potential to defoliate a wide range of conifers. Results The pest is not present in Norway or other European countries, except Russia. Natural spread and human mediated transport are potential pathways for the pest. Human mediated pathways considered are: Living trees for planting, coniferous wood in the rough and foliage and branches. There has been no import of living trees from Russia to Norway during the past 30 years, and there is currently no import of coniferous wood commodities containing bark from areas, where D. sibiricus occurs. Conclusions The probability of D. sibiricus entry by natural spread is unlikely, mainly because of the geographical distance and the partial sea barriers between Norway and the infested areas. The probability of entry by human mediated pathways is unlikely due to the very limited volume of the import. Should the pest enter Norway, the probability of establishment and spread is unlikely, due to the suboptimal climatic conditions, and the fact that the two dominant conifers in the country, Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), are intermediate and poor hosts, respectively. The potential damage, should D. sibiricus enter Norway, is considered low. Keywords: Lepidoptera, Invasive species, Geographical distribution, Forest pest
Sammendrag
Growth cessation and floral initiation in black currant and red raspberry are jointly controlled by the interaction of temperature and short-day (SD) conditions, and the processes coincide in time in both natural and controlled environments. The critical photoperiods for the two successional responses were found to be approximately 15 and 16 h, respectively, for a range of Western-European black currant cultivars. Both cessation of growth and floral initiation are promoted and enhanced by increasing temperature in the 9 to 24°C range. In contrast, biennial-fruiting red raspberry has a maximum temperature limit for growth cessation and floral initiation. At temperatures above 16°C, most cultivars grow and remain vegetative regardless of day length conditions, at 12 to 16°C they cease growing and initiate flower primordia in photoperiods <15 h, while at temperatures ≤12°C they cease growing and initiate floral primordia regardless of day length. In the annual-fruiting (primocane) types of red raspberry on the other hand, floral initiation is not constrained by high temperature, but readily takes place at temperatures up to 30°C. In addition, floral initiation is also enhanced by long day (LD) conditions in most of these cultivars. Another fundamental physiological difference is that while floral primordia of the biennial types become dormant after initiation, they proceed directly to anthesis in the annual-fruiting types. Chilling at -5°C, and in the -5 to +5°C temperature range were found to be optimal for breaking of bud dormancy and promotion of flowering in black currant and red raspberry, respectively. In black currant, 14 weeks of chilling were optimal, while for raspberry, 20 or more weeks were required for full dormancy release and promotion of flowering along the entire length of the raspberry cane. The consequences of climate warming for the production of these species in different climatic regions are discussed.
Sammendrag
SCANTURF is a joint Nordic programme for turfgrass variety testing, set up in 2005 and funded by variety entrance fees only. It replaced and simplified the former government‐funded national evaluation programmes in Finland, Sweden, Denmark and Norway. The programme includes testing of all cool‐season grasses on lawn/fairways at 15–20 mm mowing height (“lawn trials”) and optional testing of Poa pratensis L. and Lolium perenne L. on simulated football pitches with wear, mowed at 30 mm (“wear trials”). Since 2013, the program has regarded the Nordic countries as one trial zone with three test sites: Tystofte Denmark (55°15′ N, 11°20′ E), Landvik, Norway (58°21’ N, 8°32’ E) and Ylistaro, Finland (62°57′ N, 22°31’ E). Wear trials are carried out at the intermediate location Landvik only. Candidate varieties are tested against two reference varieties of the same species or subspecies. In the lawn trials, candidate varieties are evaluated for visual merit (overall turfgrass quality), winter damage, winter color, diseases and daily height growth at all three locations and for tiller density, fineness of leaves, in‐season (genetic) color, at Landvik only. Based on the results from the SCANTURF trials in 2014–2016 and 2016–2018, the candidate varieties Fabian, Tetrastar, Annecy, and Monroe (Lolium perenne), Becca, Harmonie, Traction, and Markus (Poa pratensis) and Lystig, Greenmile, and Humboldt (Festuca rubra ssp. commutata) were recommended for lawns in the Nordic countries, while Eurocordus, Columbine, Monroe, and Annecy (Lolium perenne) and Harmonie (Poa pratensis) were recommended for sports grounds. More use of the recommended varieties will have a positive effect on quality of lawns and sport grounds in the Nordic countries. Less winter injury and increasing relative performance with increasing latitude of the tetraploid perennial ryegrass variety Fabian in the lawn trials may possibly lead to more use of perennial ryegrass in the northern and more continental parts of the region.
Forfattere
Hanno Sandvik Olga Hilmo Snorre Henriksen Reidar Elven Per Arvid Åsen Hanne Hegre Oddvar Pedersen Per Anker Pedersen Heidi Solstad Vigdis Vandvik Kristine Bakke Westergaard Frode Ødegaard Sandra Charlotte Helene Åström Hallvard Elven Anders Endrestøl Øivind Gammelmo Bjørn Arild Hatteland Halvor Solheim Björn Nordén Leif Sundheim Venche Talgø Tone Falkenhaug Bjørn Gulliksen Anders Jelmert Eivind Oug Jan Henry Sundet Elisabet Forsgren Anders Gravbrøt Finstad Trygve H. Hesthagen Kjell Harald Nedreaas Rupert Wienerroither Vivian Husa Stein Fredriksen Kjersti Sjøtun Henning Steen Haakon Hansen Inger Sofie Hamnes Egil Karlsbakk Christer Magnusson Bjørnar Ytrehus Hans Christian Pedersen Jon Swenson Per Ole Syvertsen Bård Gunnar Stokke Jan Ove Gjershaug Dag Dolmen Gaute Kjærstad Stein Ivar Johnsen Thomas Correll Jensen Kristian Hassel Lisbeth GederaasSammendrag
1. Due to globalisation, trade and transport, the spread of alien species is increasing dramatically. Some alien species become ecologically harmful by threatening native biota. This can lead to irreversible changes in local biodiversity and ecosystem functioning, and, ultimately, to biotic homogenisation. 2. We risk-assessed all alien plants, animals, fungi and algae, within certain delimitations, that are known to reproduce in Norway. Mainland Norway and the Arctic archipelago of Svalbard plus Jan Mayen were treated as separate assessment areas. Assessments followed the Generic Ecological Impact Assessment of Alien Species (GEIAA) protocol, which uses a fully quantitative set of criteria. 3. A total of 1519 species were risk-assessed, of which 1183 were species reproducing in mainland Norway. Among these, 9% were assessed to have a severe impact, 7% high impact, 7% potentially high impact, and 49% low impact, whereas 29% had no known impact. In Svalbard, 16 alien species were reproducing, one of which with a severe impact. 4. The impact assessments also covered 319 so-called door-knockers, i.e. species that are likely to establish in Norway within 50 years, and 12 regionally alien species. Of the door-knockers, 8% and 10% were assessed to have a severe and high impact, respectively. 5. The impact category of most species was driven by negative interactions with native species, transformation of threatened ecosystems, or genetic contamination. The proportion of alien species with high or severe impact varied significantly across the different pathways of introduction, taxonomic groups, time of introduction, and the environments colonised, but not across continents of origin. 6. Given the large number of alien species reproducing in Norway and the preponderance of species with low impact, it is neither realistic nor necessary to eradicate all of them. Our results can guide management authorities in two ways. First, the use of quantitative assessment criteria facilitates the prioritisation of management resources across species. Second, the background information collected for each species, such as introduction pathways, area of occupancy and ecosystems affected, helps designing appropriate management measures.
Forfattere
Mekjell Meland Oddmund Frøynes Milica Fotiric Akšic Naris Pojskic Belma Kalamujic Stroil Lejla Lasic Fuad GasiSammendrag
European plum cultivars (Prunus domestica L.) are hexaploid and partially self-fertile or self-sterile requiring compatible pollinizers with overlapping bloom times. Therefore, inter-planting of different pollinizer cultivars is recommended. In order to identify successful pollinizers of the plum cultivars ‘Edda’, ‘Opal’ (self-fertile), ‘Jubileum’, ‘Reeves’, ‘Mallard’, ‘Avalon’, ‘Cacanska Lepotica’ (self-fertile), and ‘Valor’, 60 fruits per cultivar were collected from nine orchards in 2017 and 2018, all of which were located in Ullensvang, western Norway. DNA extraction was subsequently conducted from the obtained embryos, followed by genetic characterization using seven microsatellite markers. Tissue samples from all possible pollinizers were collected during the summer of 2017 and the same DNA approach was conducted. Results showed that ‘Opal’ was the most successful pollinizer among the investigated plum cultivars. The main exception was ‘Cacanska Lepotica’, which consistently displayed very high level of self-pollination. The most successful foreign pollinizer of ‘Opal’ was ‘Mallard’. However, in more than two thirds of embryos extracted from ‘Opal’ fruits self-fertilization was determined. ‘Reeves’ was identified as the most successful pollinizer among embryos collected from ‘Valor’. Among the five cultivars (‘Edda’, ‘Jubileum’, ‘Reeves’, ‘Mallard’, and ‘Avalon’) that did not display self-pollination, the pollinizer success rate of ‘Opal’, ranged from 36.5% (‘Mallard’) to 93.5% (‘Edda’) in 2017, while in 2018 this rate ranged from 43.5% (‘Jubileum’ and ‘Reeves’) up to 96.5% (‘Edda’). Overall, genotyping embryos using SSRs (simple sequence repeats) proved an effective method in determining the success rate of individual pollinizers among European plum cultivars.
Forfattere
Tatsiana Espevig Karin Normann Marina Usoltseva Jo Anne Crouch Kate Entwistle Trygve S. AamlidSammendrag
Det er ikke registrert sammendrag