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.
2008
Forfattere
Eivind Vangdal Sigrid Flatland Ingvill Kristine MehlSammendrag
Det er gjennomført forsøk med bladgjødsling i plomme i Vest-Norge. I eit forsøk vart moglege effektar av ekstra magnesium, kalium og kombinasjonen av både magnesium og kalium på avling og fruktkvalitet studert og samanlikna med eit standard bladgjødslingsprogram. I eit anna eksperiment vart verknaden av eit bladgjødslingsprogram samanlikna med berre gjødsling på bakken. Avling, fruktstorleik og viktige fruktkvalitetsfaktorar vart målt. Innhaldet av viktige næringsemne vart analysert i blad og frukter. Ingen sterke effektar av bladgjødsling med magnesium og/eller kalium vart påvist. Bladgjødslingane påverka ikkje innhaldet av næringsemne i blad og frukter så mykje at ein kunne venta signifikante utslag på fruktkvaliteten. Bladgjødslinga syntest å utsetja mogninga sidan det var tenmdensar til at fruktene var grønare og med mindre dekkfarge, var fastare og med mindre oppløyst turrstoff og meir titrerbar syre. Tendensen for kvar einskild faktor var ikkje signifikant. Dei bladgjødsla trea syntest ha høgare innhald av nitrogen og mindre av dei andre næringsemna samanlikna med kontrolltre.
Forfattere
Eivind Vangdal Sigrid FlatlandSammendrag
Norske plommedyrkarar og omsetjarar arbeider for å heva statusen til norske plommer i friskfruktmarknaden. For å sikra at berre plommer med einsarta høg kvalitet vert marknadsførde, har ein teke i bruk sorteringsmaskiner på fruktlagra. Men plommeplukkarane må øvast opp i vurdering av mogningstid ved hausting. Metodar og hjelpemiddel for å gje plukkarar og omsetjarar ei felles forståing av mogningsgrad har vorte prøvd. Ein har utarbeidd fargekart og bilete som viser mogningsgraden i dei viktigaste plommesortane som vert dyrka i Norge. Men for plommesorten "Jubileum" er den beste måten å vurdera rett haustetid fastleik. Den bærbare franske fastleiksmålaren Durofel er nyttig i slik opplæringav plukkarar til å vurdera mogningsgrad i "Jubileum". Grenseverdiar for fastleik (målt med Durofel) for ulike mogningsgrader er fastlagde.
Sammendrag
Søtkirsebærtre vart sprøyta med kalsiumoppløysing ei gong kvar veke frå krunbladfall til to veker før hausting. Frukt frå trea som hadde fått kalsiumtilførsel, hadde høgare innhald av oppløyst turrstoff. Det var ikkje signifikante skilnader i farge, fastleik og syreinnhald. Bladgjødsling med kalsium reduserte utviklinga av kutikulære frakturar på fruktene. Fruktene frå kalsiumsprøyta tre mista meir vekt under lagring enn frukter frå kontrolltre. Hjå kontrollfrukter med mange kutikulære frakturar var vekttapet større enn hjå tilsvarande frukter med få frakturar. Hjå frukter som var tilført kalsium som bladgjødsling, derimot, var det ingen skilnad i vekttapet mellom frukter med mange eller få kutikulære frakturar. Dette indikerer at dei kutikulære frakturane i kalsiumsprøyta frukt var mindre alvorlege (djupe). Innhaldet av fenoliske sambindingar var større i kalsiumsprøyta frukt enn i kontrollfrukt. Færre kutikulære frakturar, mindre alvorlege (djupe) frakturar og auka innhald av fenolar kan vera ulike mekanismar for reduksjonen i risikoen for soppsjukdomar som ein observerer i kalsiumsprøyta søtkirsebær.
Forfattere
M. Bagher Farmani Nils-Otto Kitterød Henk KeersSammendrag
A method is presented to estimate flow parameters and geological structure in the vadose zone by combining time-lapse Ground Penetrating Radar (GPR) traveltime tomography and inverse flow modeling. The traveltime tomography is used to determine the spatial electromagnetic velocity distribution in the vadose zone. These time-lapse velocity images are converted to time-lapse volumetric soil water content images using petrophysical relationships. Subsequently, the water content images are used as constraints in the flow inversion. The influence of the tomographic artifacts on the flow inversion is minimized by assigning weights that are proportional to the ray coverage. Our flow inversion algorithm estimates the flow parameters and calibrates the geological structure. The geological structure is defined using a set of control points, the positions of which can be modified during the inversion. After the inversion, the final geological and flow model are used to compute GPR traveltimes to check the consistency between these computed traveltimes and the observed traveltimes.The method is first tested on two synthetic models (a steady state and a transient flow models). Subsequently, the method is applied to characterize a real vadose zone at Oslo Airport Gardermoen, Norway, during the snowmelt in 2005. The flow inversion method is applied to locate and quantify the main geological layers at the site. In particular the inversion method identifies and estimates the location and properties of thin dipping layers with relatively lowpermeability. The flow model is cross validated using an independent infiltration event.
Forfattere
Flavio Da Ronch Line RosefSammendrag
Semi-natural grasslands are important component for the biodiversity and landscape diversity in Norway and Italy. Both regions have problems of abandonment or under-stocking of their grassland as a result of changes in livestock management during the last decades. Especially in semi-natural pastures, the grazing activity is fundamental to maintain biodiversity and landscape diversity. The effects of grazing restoration in abandoned or heavy under-stocked areas were therefore investigated in two different regions in Europe. These areas were Orkdal and Gaular in Norway and Prealpi venete in Italy. The objectives were 1: to see if the vegetation (plant functional traits) in response to grazing is the same in both regions, and 2: to see if the biodiversity response to the grazing is the same in both regions. Several pastures were investigated in both regions in order to value the effects of the grazing on the vegetation. Soil properties, plant functional traits, biodiversity and pastoral value were studied before and after the restarting of grazing in both areas. Grazing activities influence floristic composition in Italy more than in Norway. There were no significant changes in the soil properties in both regions. Shannon Index show an increase consequently to grazing restoration.
Sammendrag
In Central-Norway, Anthriscus sylvestris, Deschamspia cespitosa and Alnus incana are well known re-growth species in abandoned areas. They often dominate abandoned areas and reduce the species biodiversity. Objectives of these field-studies were to find proper management strategies that reduce the plant cover of A. sylvestris, D. cespitosa and A. incana in semi-natural grasslands and thereby conserve or increase the biodiversity. In road-verges dominated by A. sylvestris management studies by different mowing strategies was recorded during four years. The response of D. cespitosa, A. sylvestris and A. incana to four different grazing regimes was investigated in abandoned grasslands for four years. Results from the field studies show that areas dominated by these species request specific, extraordinary, intensive and long-term management strategies.
Sammendrag
This work clearly demonstrates that the farming practices affect the species composition in semi"natural grasslands, and differs from location to location. Therefore, the former management and succession phase have to be identified for each semi"natural grassland so that the correct farming practices can be used.
Forfattere
Trygve S. Aamlid Mats Larsbo Nick JarvisSammendrag
Water repellency in golf putting greens may induce preferential `finger flow" leading to enhanced leaching of surface applied fungicides. We examined the effects of root zone composition, treatment with a non-ionic surfactant and use of either the fungicide iprodion (3-(3,5-dichlorophenyl)-N-(1-methylethyl)2,4-dioxo-1-imidazoline-carboximide) or a combination of azoxystrobin (Methyl (E)-2-{2-[6-(2-cyanophenoxy) pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate) and propiconazole (1-[[2(2,4-Dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]1-H-1,2,4-triazole) on soil water repellency, soil water content distributions, fungicide leaching and turf quality during one year. Soil water repellency was measured both using the water drop penetration time test and tension infiltrometers. Our study was made on a three year old experimental green seeded with creeping bentgrass (Agrostis stolonifera L.) `Penn A-4" at Landvik in SE Norway. The facility consists of 16 lysimeters with two different root zone materials, i) straight sand (1% gravel, 96% sand, 3% silt and clay, 0.4% (w/w) organic matter) (SS), and ii) straight sand mixed with garden compost to an organic matter content of 2.1% (Green Mix (GM)). Results showed that surfactant treatment reduced soil water repellency and the spatial variation in soil water contents. Fungicide leaching was close to zero for the GM lysimeters probably due to stronger sorption. Concentrations in the drainage water from SS lysimeters often exceeded surface water guideline values for all three fungicides, but surfactant treatment dramatically reduced fungicide leaching from these lysimeters. In autumn and winter, surfactant treated plots were more infected with fungal diseases probably because of higher water content in the turfgrass thatch layer.
Forfattere
Trygve S. AamlidSammendrag
The sand used for green construction is usually amended with peat or compost, but there is no requirement for organic amendment (OA) of USGA green rootzones. The objective of this experiment was to compare USGA greens constructed with various root zone compositions. The experiment was conducted in the turf lysimeter facility at Bioforsk Landvik (58º20"N, 12 m a.s.l., 30 yr mean annual temp. 6.9ºC, 30 yr mean annual rainfall 1230 mm) from Sep. 2003 to May 2007. The sand used in green construction had 13% very coarse sand (>1.0mm), 74% coarse and medium sand (0.25-1.0 mm), 7% fine sand (0.15-0.25 mm), and 6% fine particles (
Sammendrag
Commercial strawberry production in Scandinavia started as early as the 1920s, with the cultivar `Abundance". Although the production area was about 1500 ha, the yield was very low (< 3 t ha-1). In the 1960s Scandinavia had a large increase in strawberry area and yield per hectare. The strong development of strawberry production came after the introduction of the cultivar `Senga Sengana", new growing techniques (black polyethylene mulch) and the release of new and more efficient fungi- and herbicides. Over the past 30 years, the yield and growing area has stabilized, although the number of strawberry growers has decreased strongly. Today, Scandinavia has a strawberry production of about 8500 ha, yielding about 75 000 tons of berries in a very short summer-season. Almost all strawberry growing is perennial production with single-cropping (SD) cultivars in open field, and the fields are normally kept for 3-5 years. The main strawberry cultivars grown today are `Korona", `Polka", `Honeoye", `Jonsok" and `Florence". The area of `Sonata" is increasing. While almost all strawberries up to the 1970s were picked and sold through a "pick-your-own" system, today, almost 95% is sold through wholesale dealers for fresh consumption, and only a small amount is frozen for processing. Since the mid 1990s, there has been a slow decrease in the strawberry production area in Scandinavia. This is due to an over-production of strawberries in a short, hectic season, giving very low prices. To avoid this, attempts are being made to extend the season, especially with row cover, plastic tunnels, stored plants and new cultivars (including everbearing cvs.). The growing area covered with polyethylene tunnels are now increasing in all the Scandinavian countries. The area of raspberry in Scandinavia was stable up to the 1990s, with a production of about 500 ha. The production was mainly for the processing industry with old Norwegian and Finnish cultivars. Since 1995, the raspberry area has doubled, and is still increasing. This came after introduction of the Scottish cultivar `Glen Ample", which has shifted the production from mainly for the processing industry, over to mainly for fresh consumption. This development was started in Norway, and the other Scandinavian countries are following up. Introduction of `Glen Ample" has given the growers new possibilities to increase their income, and the focus on extending the season and on berry quality, have increased. About half of the Norwegian raspberry production is now under polyethylene tunnels, and this leads again to new possibilities of extension of the season by growing long canes or primocane-fruiting varieties like `Polka". Less than 120 ha of blueberries are produced in Scandinavia. The yields are low, and the picking cost too high. But, there is increasing interest, related to health benefits, from the marked. The main challenges for berry production in Scandinavia are access to and cost of labour, and how to meet the increased competition from imported berries. The Scandinavian countries have also strong restrictions in the number, and use of pesticides. Increased focus on taste and quality will be important in the future.