Hopp til hovedinnholdet

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.

2008

Abstract

The frequency with which ewe lambs lay on wooden surfaces at two levels, called ``double bunks,"" was documented by video recording at 6, 11 and 18 months of age: the number in each of 4 pens (n = 4) lying either on double bunks (DBs) or on the expanded metal floor (EMF) was recorded. At 6 months, lambs were sheared half way through the research period and DBs of two different heights (50/60 cm) and depths (60/75 cm) were tested. At other ages the lambs were sheared before testing and all DBs were the 60 cm 60 cm design. Fully fleeced lambs aged 6 months preferred to lie on EMF rather than DB (P < 0.001). After shearing, the use of EMF for resting declined (P < 0.05) and no significant preference between EMF and DB was found. The lambs tended to lie less when newly sheared (P = 0.06). At 11 months, sheared lambs used DB just as much as EMF, whereas 18 month old sheared ewe lambs tended to choose DB to lie on (P = 0.09). At 6 months, there was a tendency for more lambs to rest at ground level in the DB when headroom was higher at 60 cm (P = 0.1). No other preferences between DB designs were found. The results are discussed according to the regulations for organic sheep farming in Norway. The lambs showed little preference for resting on a DB compared to EMF, so there is insufficient evidence to recommend a two-level, wooden lying area for sheep.

2007

Abstract

The study aims to estimate the effects on the sheep farm economy of reducing grazing levels necessitated due to possible overgrazing by sheep on two important mountainous range pastures in southwest Norway. The pasture range in Setesdal Vesthei is grazed by sheep from distant farms located at Jæren (south of Stavanger), while south-western Hardangervidda is grazed by sheep from local farms and distant farms located along the coast. Farmers utilizing the pasture areas combine sheep with dairy cows, off farm work or businesses, while the local farms combine it with orchards. A Linear Programming (LP) model for specialized sheep farms based on farm records has been developed to study effects of reaching various grazing capacity levels. Reducing the number of sheep in Setesdal Vesthei by 10 percent would lower farm income per breeding stock animal with € 15 to € 119 and with € 35 to € 211 for Hardangervidda. The decrease in annual income will range from € 15,00 to € 119,00 in total for the farms using Setesdal Vesthei. The economic effects depend much on meat production per ewe. Replacing unilateral sheep grazing with a mixed system involving suckling goats and heifers is discussed to deal with the problems of encroachment and increasing elevation of the alpine tree-line.

Abstract

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.

Abstract

This article examines innovation processes in forest recreational services on the basis of case studies in five European countries with differing institutional backgrounds of forest ownership and access rights. The analysis reveals that forest-related recreation services are developed under varying institutional conditions and on public as well as private land. Ideas for innovations in recreational services may come from within but often outside the forestry sector. Financing is provided from public and private sources. Both public and private spheres have important roles in providing natural, human and financial resources and usually a network of public and private actors are involved in innovation processes. Of particular importance are cross-sectoral interactions between forestry and tourism. Greater institutional support is needed for the development of forest-related recreation services because the field is at an early stage of development. It is concluded that support should focus on providing ideas and financial resources for product development and on facilitating cross-sectoral interaction between forestry and tourism actors. A particular need is seen for development of models for durable interaction between land owners and tourism operators on a regional scale.