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
Abstract
Capercaillie Tetrao urogallus leks have repeatedly been reported to be located in old forest. However, two conditions may have biased this widely held view. First, leks are known to be continuously used over several decades, and therefore might have been established when forest stands were younger. Second, stand -replacement logging (clearcutting) was not widely applied until the 1950s, leaving even-aged regenerating stands too young for leks to have been established in the latter part of the 20th century. Here we report eight cases of lek formation in young plantations from south-central Norway. Stand age ranged within 2646 years when display activity started. At six of the sites, we confirmed that females were regularly feeding on pine trees in winter prior to lek establishment, and at four of these sites displaying males were observed courting the females in late winter. These findings support the hotspot model of lek formation put forward by Gjerde et al. (2000), and it offers promising options for managing capercaillie leks in commercially utilised forests.
Authors
Susanne Eich-Greatorex Trine A Sogn Anne Falk Øgaard Ivar AasenAbstract
The objective of the present study was to investigate the influence of soil organic matter content and pH on plant availability of both inorganic and organic selenium (Se) fertilisers. Further, the risk of Se leaching after application of inorganic Se fertiliser was evaluated. A new interpretation of an older field study at different sites in Southern Norway showed that organic C was correlated with grain Se concentration in wheat, barley and oats, explaining up to 60% of the variation in Se concentration. Pot experiments with a peat soil, a loam soil and a peat/loam soil mixture were conducted for the present study at a range of pH values between pH 5 and 7. Below pH 6, Se uptake from added Se fertiliser was higher in the soil types with high organic matter content than in the loam. The opposite occurred at a soil pH above 6, where Se uptake was higher in the loam than in the peat soil. A simple leaching experiment after one growing season confirmed the findings of the pot experiments that Se availability in the loam soil with a relatively low organic matter content increased with increasing pH, whereas it decreased in the peat soil. Neither Se yeast, nor pure Se methionine, used as organic Se fertiliser, resulted in any significant uptake of Se when added at concentrations similar to the inorganic Se applications.
Abstract
High mortality among chicks, due to fragmentation and changes in habitat caused by commercial forestry, is considered one of the main reasons for the general decline in capercaillie Tetrao urogallus in boreal forests. Using GPS satellite telemetry, we studied the movement patterns of young capercaillie broods: 1) to test if this new technology could be applied to gain more detailed insight into behaviour and habitat selection at a small spatial scale, and if so, 2) to compare the broods' relative use of planted and older, naturally regenerated forests. Hens of four broods with chicks 2-7 days old were captured and fitted with 90-g backpacks containing GPS units and VHF transmitters. The GPS units were programmed to record positions every 15 minutes, the shortest interval possible. With a storage capacity of 450 positions, movements could be monitored for ca 4.5 days. In our study area (Varaldskogen) with moderate topography, the GPS technology performed quite well. A total of 1,277 positions were obtained (84% of potential maximum), of which 77% were within 20 in of the true position of the brood. The movement patterns of the four broods were quite similar, with a mean speed of 83.2 m +/- 9.9 (SE) per hour during the 4.5-day tracking period. Broods moved almost continuously during the 24-hour cycle, presumably foraging, although their speed was slower at night. The two oldest broods whose initial age was seven days moved faster than the two younger broods whose initial age was two and three days, respectively. Strong autocorrelation among successive positions made us examine habitat selection using a binominal choice method for each brood separately. When broods were inside old 'natural' forest, they remained there instead of moving into plantations. When inside plantations, they did not discriminate between remaining there and moving into nearby old forest, but they tended to move faster in plantations than in old forest. Clearly, the new, cost-effective GPS telemetry offers new and better opportunities for studying small-scale brood movement. Very frequent and accurate positions can be obtained without either disturbing the birds or leaving scent marks that may attract predators.
Abstract
Urbanization and an increasingly globalized food system cause growing physical and psychological distances between producers and customers. Alternative distribution initiatives with direct sale to local customers are emerging. This paper reports results of two surveys, one from producers and one from customers, in the newly introduced Norwegian farmers market system. The main aim of the research was to examine attitudes toward local foods and evaluate the potential of this new marketing channel to reduce the distances between farmers and consumers. Results show that producers were more concerned than customers regarding knowledge on how food was produced, and locally marketed, although customers were also interested in these issues. Both groups regarded as to how food was produced to be more important than where it was produced. Producers were more interested in giving customers information on agriculture than customers were in receiving this information. The attitudes toward food differed between respondents of larger urban cities and smaller cities in Norway. Producers traveled a longer distance (average 79 km) than customers (average 14 km) to come to the markets, but traveling distance differed substantially among the sites owing to market location, number of local farmers and small-scale local processors, and product diversity. Results suggest that the farmers markets have potential to reduce both physical and social distances between producers and consumers, and thereby contribute to the sustainability of local food production. Understanding farmer and consumer attitudes can contribute to organization and promotion of farmers markets in Norway and elsewhere. doi:10.1300/J064v30n04_06.
Authors
Inge Stupak Antti Asikainen M Jonsell E Karltun Anders Lunnan Nicholas ClarkeAbstract
The substitution of fossil fuels by biomass in energy consumption is a measure to decrease the emission of greenhouse gases and thereby mitigate global warming. An increased use of wood-based biomass for energy can also, if well managed, enhance the socioeconomic benefits from forests, particularly for small forest owners substituting purchased energy resources with their own wood fuels. At both European and national levels, political plans exist for an increased use of forest biomass for energy. However, the potential negative impact on the forest ecosystem and the surrounding environment due to an increased utilisation of wood-based biomass for energy needs also to be considered. The increased use of wood-based biomass must be fully in accordance with the principles of sustainable forest management, for example as outlined by the pan-European Ministerial Conference on the Protection of Forests in Europe.
Abstract
The relationships between measures of forest structure as derived from airborne laser scanner data and the variation in quantity of young trees established by natural regeneration in a size-diverse spruce forest were analyzed. A regeneration success rate (RSR) was regressed against 27 different laser-derived explanatory variables. The 27 different models were ranked according to their Akaike information criterion score. Each laser variable was then associated with two categories. These were return and type. Within the return and type categories, the variables were grouped according to if they originated from first or last return echoes and if they were canopy height or canopy density metrics. The results show that the laser variables strongest correlated to the quantity of small trees could be attributed to last return and density metrics.
Authors
Anssi Niskanen Anders Lunnan Ikuo Ota Keith Blatner John Herbohn Lyndall Bull Ian Ferguson Gordon M HickeyAbstract
Many demand and supply-side policies impede or foster forestry entrepreneurship. A study was conducted to consolidate existing knowledge on policies influencing forestry entrepreneurship in Finland, Norway, Japan, Australia, the Philippines and the USA, and to draw conclusions on these impeding and fostering factors. From the country studies it was difficult to find common structures on policies affecting forestry entrepreneurship. This is understandable because most policies in forestry are aimed at supporting sustainable forest management, wood production and ecological services of the forests rather than entrepreneurship as such. Despite the high variety of policies applied in the study countries, it can be concluded that strict public control on forests? use and management potentially impedes forestry entrepreneurship. While these policies assist to correct market failure and to promote sustainability of forest management, they may also result into unnecessary and ineffective regulations that limit the opportunities for forestry entrepreneurship. A common feature promoting the demand for forestry entrepreneurship in some of the countries studied is the strong emphasis on forestry cooperatives, which were important institutions to support small-scale forestry entrepreneurship. In many study countries, different ad hoc programs are implemented to find new economic and entrepreneurial opportunities aside from the current use of wood and forests. Subsidies and tax incentives are commonly applied to reduce risks from making forestry investments or otherwise increase the economic return from timber production.
Authors
Gudbrand Lien Ståle Størdal Sjur BaardsenAbstract
In Norway, as in many other European countries, income from forestry has become marginal to owners? household economies and most employment of forest-owner households is now undertaken off the property. Also, many forest owners have focused increasingly on other revenue-earning activities on their properties, such as providing recreational services. It is a challenge in all kinds of production to find the optimal way of converting inputs into outputs, i.e., to be technically efficient. Extent of financial dependency on income from forestry differs between part-time and full-time forest owners. Since the two groups have different livelihood strategies, it is plausible that full-time forest owners have more professional forest management practices. Data for a cross-section of 3,249 active (i.e., harvesting) forest owners were extracted from the 2004 Sample Survey of Agriculture and Forestry representing the year 2003. A stochastic production frontier analysis was applied to evaluate forest management efficiency impacts of important factors including property and owner characteristics, outfield-related and agricultural activities, off-property income and geographical location in central or remote areas. It was found that many forest owners are technically inefficient, and there exist opportunities for improved performance. Off-property income was found to have an estimated negative impact on technical efficiency, the inefficiency arising (weakly) with increasing share of household incomes from outfield activities, and properties in urban centred areas are less efficient than those in remote areas. One policy implication of the study is that a potentially substantial efficiency increase might be achieved from allowing small inefficient woodlots to merge into larger units of forestry production. Also, providing support for forest management plans may improve efficiency.
Authors
Trond Henriksen Audun Korsæth Tor Arvid Breland Bo Stenberg Lars Stoumann Jensen Sander Bruun Jon Gudmundsson Fridrik Palmason Anders Pedersen Tapio SaloAbstract
Mechanistic, multi-compartment decomposition models require that carbon (C) and nitrogen (N) in plant material be distributed among pools of different degradability. For this purpose, measured concentrations of C and N in fractions obtained through stepwise chemical digestion (SCD) and values predicted from near-infrared (NIR) spectra or total plant N concentration were compared. Seventysix cash, forage, green manure and cover crop plant materials representing a wide range in biological origin and chemical quality were incubated in a sandy soil at 15 degrees C and -10 kPa water potential for 217 d. A mechanistic decomposition model was calibrated with data from soil without plant material and initialised by data on amounts of C and N in fractions obtained from SCD directly or C and N in SCD fractions as predicted from NIR spectroscopy or plant N concentration. All model parameters describing C and N flows from plant material were kept at default values as defined in previous, independent works with the same model. When results from SCD were used directly to initialise the decomposition model, C and N mineralisation dynamics were predicted well (r(2) = 0.76 and 0.70 for C mineralisation rates and accumulation of inorganic N, respectively). When a NIR calibration was used to predict the SCD data, this resulted in nearly equally good model performance (r(2) = 0.76 and 0.69 for C and N mineralisation, respectively). This was also the case when SCD data were predicted from plant material N concentration (r(2) = 0.76 and 0.69 for C and N). We conclude that the combined use of a mechanistic decomposition model and quality data from SCD is a highly adequate basis for an a priori description of the mineralisation of both C and N from common agricultural plant materials, and that both NIR spectroscopy and measurement of total N concentration offer good and cost-effective alternatives if they are calibrated with SCD data. (C) 2007 Elsevier Ltd. All rights reserved.
Authors
Roald Sørheim John Eirik Paulsen Arild Saasen Jerome Leleux Arnaud Albouy Trond Knapp Haraldsen Per Anker Pedersen Thomas Hartnik Roar LinjordetAbstract
This paper presents the potential of composting oil wet drill cuttings as a drilling waste disposal option. The potential is substantiated by results from several laboratory and field experiments. Artificially oil wetted drill cuttings were prepared by adding commonly used base oils from Norwegian offshore operations to a representative clay. Degradation of the hydrocarbon components in the oily wet cuttings by vermicomposting was successfully accomplished. The composts were beneficially used as part of growing media for landscape plants; ryegrass, coniferous, and deciduous trees, and the fertilization effect was compared with commercial NPK fertilizers. The plant growth studies showed that the composts produced by treating artificial oily drill cuttings by vermicomposting had considerable fertilizing effect on ryegrass and trees.