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.
2012
Sammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
2010
Sammendrag
No abstract has been registered
Sammendrag
We have mapped the quality of pasture resources for sheep grazing outdoor all year on ten localities along the west coast of Norway, using a classification scheme developed for this purpose. The classes reflect fodder value throughout the year. We performed an accuracy assessment, and identified possible sources of error. The accuracy is relatively low, and like others, we found that separating heath classes is a challenge. However, most errors can be explained by special mislocation and temporal change. Our further work with exploring grazing habits and landscape use of Old Norse sheep will include a GPS study of sheep movements overlaid with our pasture maps. We will update the map on that locality through field visits to enhance its accuracy.
Sammendrag
No abstract has been registered
2009
Sammendrag
Analysing forest history is crucial to understanding how shifting harvesting methods have different effects on forest landscape structure. Two main harvesting regimes in a Norwegian boreal forest landscape over a period of 150 years were detected by the study. A homogeneous impact regime resulting from selective logging changed the forest structure by logging the oldest and largest trees evenly throughout the forest, resulting in a homogeneous landscape structure. However, population growth in the 19th century led to a substantial increase in traditional subsistence forestry to obtain building materials, firewood, etc. The most intensive stage of this regime started in c.1860 when farmers began selling logging contracts to companies and timber traders. Despite this being termed a homogeneous landscape impact, the actual exploitation of the forest was strongly influenced by local factors such as the location of farms, summer farms, lakes, and rivers. Clear-cutting from the 1950s has resulted in a new heterogeneous impact regime, giving a landscape structure dominated by patches of even-aged stands. This regime still predominates. The analysis is based on a study of Nordli and the Sandøla drainage basin in Nord-Trøndelag. Such studies should give a better understanding of the interaction between natural ecological conditions in and human impact on boreal forest landscapes.
Sammendrag
No abstract has been registered
Forfattere
Bolette Bele Hanne Sickel Tor Lunnan Ann Norderhaug Marianne Østerlie Roger K. Abrahamsen Liv Sigrid Nilsen Mikael OhlsonSammendrag
No abstract has been registered
2008
Forfattere
Aslaug Helgadottir Petter Marum Sigridur Dalmannsdottir Kristin Daugstad Thordis Anna Kristjansdottir Tor LunnanSammendrag
Background and aims: White clover (Trifolium repens) is an important component of sustainable livestock systems around the world. Its exploitation for agriculture in the northern, marginal areas, is, however, currently limited by the lack of cultivars that combine persistence and high production potential. The aims are to investigate whether it is feasible to create breeding material of white clover for these areas by combining winter hardiness of northerly populations with good yielding ability of more southerly cultivars. Methods: A total of 166 crosses of 14 different parental combinations between winter-hardy, low-yielding populations of northern origin and high-yielding commercial cultivars of more southerly origin were tested under field conditions in Iceland and Norway and the parental combinations were compared in Norway. Spaced plants were transplanted into a smooth meadow grass (Poa pratensis) sward. Dry matter yield was estimated for 2 years after planting in Norway and morphological characters associated with yielding capacity were measured at both sites. Key results: The results showed that southerly cultivars had larger leaves and higher yielding potential than northern types but suffered more winter damage. Significant variation was found between full-sib families within the different parental combinations for all morphological characteristics measured in all three trials. However, it was difficult to detect any consistens morphological patterns between progeny groups across trial sites. No significant correlations were found between leaflet area and survival. Conclusions: The present study has confirmed that it should be possible to simultaneously select for good winter survival and larger leaves and, hence, higher yielding ability under marginal conditions.
2006
Sammendrag
No abstract has been registered