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.
2007
Authors
Mekjell MelandAbstract
During the period 1998-2000, thinning trials were conducted using bloom thinners on mature European plum trees at Ullensvang and at fruit growers sites in western Norway. In 1998, unsprayed control and handthinned `Victoria" trees were compared with trees treated at full bloom with a single application of 1% Armothin® or 1.5% ammoniumthiosulphate (ATS). The same program was conducted in the following two years with the addition of a single full bloom treatment with 250 ppm ethephon and a post-bloom application one month after full bloom with the mixture 10 ppm 1-napththaleneacetic acid (NAA) and 75 ppm ethephon. High volume sprays were conducted the first two years and low volume the last year. Thinning trials testing 1-1.5 % ATS and 5-7 % lime sulphur in comparison with unthinned and handthinned trees to the cultivars `Opal" and `Victoria" were conducted in 2000, at growers sites. Generally, thinning treatments reduced crop load and enhanced fruit quality (fruit size, soluble solid content, fruit firmness and ground and surface colour), but the results varied from year to year. Fruit set was reduced to about half of control values and the percentage of class 1 fruits was doubled compared to the control trees. High volume sprays to running off was more effective than low volume. The cultivar `Opal" was more sensitive to ATS than `Victoria" and a low dosage recommended. All thinning compounds caused some minor leaf injury but no fruit damage. The flower thinners were efficient at rather low temperture. No differences in the amount of gummosis (internal disorder of the fruits) were observed due to treatments on the `Victoria" plums. Return bloom was improved by thinning. In conclusion, a single dilute application at full bloom of 1% Armothin®, 1.5% ATS or 250 ppm ethephon or one application of the mixture 10 ppm NAA-75 ppm ethephon four weeks after bloom reduced fruit set and crop load and increased the fruit quality and return bloom to the cultivar `Victoria". Similar results gave one dilute spray with 1 % ATS or 5 % lime sulphur at full bloom to the cultivar `Opal".
Abstract
No abstract has been registered
Authors
Clemens Reimann Arnold Arnoldussen Peter Englmaier Peter Filzmoser Tor Erik Finne Robert G. Garrett Friedrich Koller Øystein NordgulenAbstract
Rock samples and the C-, B- and O-horizons of soils developed on these rocks were collected in forested areas along a 120-km south–north transect in southern Norway, passing through the city of Oslo. Forty samples (1 site/3 km) were analysed for 37 chemical elements (Ag, Al, As, Au, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sc, Se, Sr, Te, Th, Ti, Tl, U, V, W and Zn) following an aqua regia digestion; pH (water extract) and loss on ignition were also determined. The O-horizon soils were additionally analysed for Pt. Gold is the only element that shows a clear anthropogenic peak in the O-horizon soils collected from the city of Oslo. Silver, Au, Bi, Cd, Hg, Pb, S, Sb, Se and Sr all show a strong enrichment in the O-horizon when compared to the underlying C-horizon or the bedrock along the full length of the transect. Neither geology nor anthropogenic input of elements dominate the observed patterns. The most important factors for the observed element concentrations in the O-horizon are weathering, uptake (or rejection) of elements by plants and the kinetics of decay of the organic material in the O-horizon. Climate, especially temperature and precipitation, has an important influence on the formation and decay rates of the organic soil layer. Acid precipitation will delay the decomposition of the organic layer and lead to a natural enrichment of several metals in the O-horizon. Land use change, deforestation and liming can all increase the decay kinetics of organic matter and thus result in a release of the stored element pool.
Authors
Clemens Reimann Arnold Arnoldussen Rognvald Boyd Tor Erik Finne Friedrich Koller Øystein Nordgulen Peter EnglmaierAbstract
Forty samples each of leaves of birch (Betula pubescens Ehrh.), European mountain ash (Sorbus aucuparia (L.)) and bracken fern (Pteridium aquilinum (L.) Kuhn) as well as spruce needles (Picea abies (L.) Karsten) were collected along a 120 km south–north transect running through Norway\"s largest city, Oslo. Concentrations of 25 chemical elements (Ag, Au, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sr, Ti, and Zn) as well as loss on ignition for the 4 sample materials are reported. The decline of input of sea spray with distance from the coast, geology, pH and anthropogenic contamination all played a role for the observed element concentrations in the leaves. Although growing under exactly the same natural conditions each plant species displayed quite unique uptake characteristics. Plant-species dependency and individual differences in the reaction of the plant leaves to different element sources make the investigated species of very limited value as bioindicators of anthropogenic activities. Anthropogenic contamination influences plant-leaf element content within a limited distance ( 20 km) from the source.
Authors
Clemens Reimann Arnold Arnoldussen Tor Erik Finne Friedrich Koller Øystein Nordgulen Peter EnglmaierAbstract
Forty samples each of leaves, bark and wood of mountain birch (Betula pubescens EHRH.) were collected along a 120 km long south-north transect running through Norway\"s largest city, Oslo. Concentrations of 26 chemical elements (Ag, As, Au, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sr, Ti and Zn) as well as loss on ignition for the three sample materials are reported. By far the highest concentrations of most elements appear in the leaves. Prominent exceptions are Au and Pb, both of which are enriched in wood, indicating the importance of root-uptake, and As which is enriched in bark. Bedrock lithology, ore occurrences, soil pH and urban contamination all have a visible influence on the element concentrations in mountain birch leaves, bark and wood. It is often impossible to differentiate between all the factors that can influence element concentrations in the three sample materials. Mountain birch bark shows the strongest anthropogenic impact of the city of Oslo for dust-related elements (Fe, La, Ti) and Sb. Even in mountain birch bark the influence of the city on element concentrations is no longer discernible from the background variation at a distance of less than 20 km from Oslo centre. Compared to terrestrial moss, mountain birch appears to be of little value as a biomonitor for urban contamination.
Abstract
No abstract has been registered
Authors
Kjersti Holt HanssenAbstract
No abstract has been registered
Authors
Erlend Nybakk Eric N. HansenAbstract
This study is an investigation of the nature-based recreation services industry in Norway. A recent study in Forest Policy and Economics identified two main elements of entrepreneurship, the ability to recognize business opportunities and the ability to take calculated risks. Further, that study examined how entrepreneurial attitudes affect the probability for start-ups. It is suggested that entrepreneurial attitudes influence the likelihood for process innovation and increased performance. Entrepreneurship and innovation theory were used and an e-mail survey was conducted. The questionnaire was forwarded to 324 Norwegian micro-enterprises selling forest recreation services. The response rate was 55 percent. Respondents that exhibit a stronger entrepreneurial attitude appear more likely to change the way they organize their enterprise and tend to have higher income growth.
Abstract
Ecological studies are often confronted with short and fragmented or unevenly sampled time series. Examples are, e.g., time series of biogeochemical fluxes measured on a variety of scales. Characterizing the observed time series patterns, particularly the correlation structure is crucial for an integrated ecosystem assessment or possibly for improved processes understanding.
Authors
Trygve S. Aamlid Hans Martin Hanslin Bjørn Molteberg Åge Susort Anne Steensohn Frank Enger Palle HaalandAbstract
Twelve fertilizer/biostimulant products or product families were compared with mineral fertilizer in three two-year trials on USGA greens and sand-based football fields in southern Norway. Within each trial, all treatments were received the same amount of total nitrogen per year. Substitution of some of the mineral fertilizer with Gro-Power® improved turfgrass quality in one trial. Otherwise, the organic fertilizers and biostimulants producted results that were equal to or inferior to the control treatment. In conclusion, fertilization of sand-based golf greens and football fields ought to be based on light and frequent applications of mineral fertilizer throughout the growing season. Organic fertilizers and biostimulants can, at best, be supplements to such a fertilizer program.