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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.

2013

Abstract

Norway spruce (Picea abies (L.) Karst.) is one of the most important coniferous species in Europe both from an economic and ecological point of view. Solid wood products and pulp and paper products have the largest economic value. The patterns of variation observed in Norway spruce provenance trials show geographic variability on a large scale. Genetic variation is also present among offspring from natural populations within the same provenance region and among progenies from trees in the same population. This variation can often be larger than the variability among provenances. Tree improvement of Norway spruce started in Europe in the late 1940s. Breeding programmes were initiated in nearly all European countries but with different intensities. A common objective has been to create base material for seed procurement. Breeding objectives differ between countries, but most of them include adaptation and health, volume production and wood quality in some way. Genetic gains in volume per area unit from first round of seed orchards is around 10 % and from new seed orchards established with tested material expected to be between 20 and 25 %.

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Abstract

Sallow (Salix caprea L.) and rowan (Sorbus aucuparia L.) constitute small proportions of the deciduous tree volume in Scandinavia, but are highly preferred winter forage for moose and red deer, which occur at historically high densities. Thus, a possible decline of these tree species has been indicated. Against this background, we have reviewed the life histories of relevance for browsing, as well as the basic biology and genetics of sallow and rowan. The species show similarities with respect to short lifespan, small size and sympodial growth pattern, which are risk factors in a browsing context. They also have high juvenile growth rate, important for growing quickly out of reach of browsers. Sallow depends strongly on disturbance for establishment and is more demanding with respect to soil and light conditions than rowan, possibly important for the substantially lower abundance of sallow on the Norwegian Forest Inventory plots. Similarly, the relative recruitment of small size classes of sallow is less than for rowan. Although recruitment is reported to be hampered in wintering areas with high moose or red deer densities, the inventory data, however, dating only back to 1994, do not suggest a general decrease in any of the species. Sallow and rowan saplings show low mortality in moose and deer dominated areas and the species can be characterised as rather resilient to browsing. Of more concern is that browsing can constrain the development of mature rowan and sallow trees locally, with possible consequences for associated epiphytic biodiversity.

Abstract

Environmentalists tell us that we’re loosing species at an increasing rate, and if we are to stop the cascading extinctions by 2020 (which we have agreed upon in international conventions) we need to take immediate action. Making sure we’re not loosing any ’native’ species may seem a daunting task, especially if we look at insects, spiders, fungi, and other tiny creatures that live in dead wood. For thousands of these saproxylic species the wood and timber that we are harvesting make up the bread and butter of their everyday life. The competition is fierce, and it doesn’t get any better when we remove most of the wood that otherwise would have become their future homes. What shall we do?