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.
2011
Authors
Per Stålnacke Geoffrey Gooch Sekhar Udaya Nagothu Ingrid Nesheim Line Johanne Barkved Bruna Grizzetti Johannes Deelstra Håkon Thaulow Dag BergeAbstract
No abstract has been registered
Abstract
Frequent bark beetle outbreaks cause biome-scale impacts in boreal and temperate forests worldwide. Despite frequent interceptions at ports of entry, the most aggressive bark beetle species of Ips and Dendroctonus in North America and Eurasia have failed to establish outside their original home continents. Our experiments showed that Ips typographus can breed in six North American spruce species: Engelmann spruce, white spruce¸ Sitka spruce, Lutz spruce, black spruce and red spruce. This suggests that differences between the Eurasian historical host and North American spruce species are not an insurmountable barrier to establishment of this tree-killing species in North America. However, slightly diminished quality of offspring beetles emerged from the North American spruces could reduce the chance of establishment through an Allee effect. The probabilistic nature of invasion dynamics suggests that successful establishments can occur when the import practice allows frequent arrivals of non-indigenous bark beetles (increased propagule load). Model simulations of hypothetical interactions of Dendroctonus rufipennis and I. typographus indicated that inter-species facilitations could result in more frequent and severe outbreaks than those caused by I. typographus alone. The potential effects of such new dynamics on coniferous ecosystems may be dramatic and extensive, including major shifts in forest structure and species composition, increased carbon emissions and stream flow, direct and indirect impacts on wildlife and invertebrate communities, and loss of biodiversity.
Authors
Liv Jorunn HindAbstract
From February 2010 to March 2011, this preliminary project was dedicated to initiate partners from Norway, Iceland and Greenland to design and develop a proposal for a main project. NORA and Nordland fylkeskommune was financial partners in this preliminary project. The application for the main project was submitted to NORA by March 1st 2011.
Editors
Stig A. BorgvangAbstract
No abstract has been registered
Authors
John Marshall Bryden Julie Nåvik Hval Fabio de Menna Kjersti NordskogAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Johannes BreidenbachAbstract
The aim in the analysis of sample surveys is frequently to derive estimates of sub-population characteristics. This task is denoted small area estimation (SAE). Often, the sample available for the sub-population is, however, too small to allow a reliable estimate. Frequently, auxiliary variables exist that are correlated with the variable of interest. Several estimators can make use of auxiliary information which may reduce the variance of the estimate.
Authors
Gunnhild Søgaard Inger Sundheim Fløistad Aksel Granhus Kjersti Holt Hanssen Harald Kvaalen Tore Skrøppa Arne SteffenremAbstract
No abstract has been registered
Abstract
AR-FJELL is the Norwegian land resource database for the mountain areas. AR-FJELL is not distributed as a separate product from Skog og landskap, but does – together with topographic data (series N50) from the Norwegian Mapping Authority (Statens kartverk) form the basis for the classification of mountain areas in the national land resource maps AR50 and AR250. The five Norwegian AR-FJELL classes are documented through descriptive statistical “profiles” of the actual content of each class. Profiles of the AR-FJELL classes were obtained through a GIS overlay operation between AR-FJELL and the available AR18X18 (Land resource accounting for the Norwegian outfields) survey plots. The distribution of vegetation classes for each AR-FJELL class was compiled from this overlay. The report also consider the distribution of the AR-FJELL classes by elevation asl and the distribution of the vegetation types in the AR18X18 sample. AR18X18 is (2011) only available for parts of Norway. The study should be repeated when a full national coverage is available. This is expected in 2015. The study was carried out with funding from the Norwegian Space Centre.
Abstract
The centennial volume of this journal provides a fitting time to stop and reflect. Do we know where we are heading? Are we progressing in the right direction? Having studied landscape change for some years, we have seen the tremendous power of engagement that can be found in landscapes. Landscape is a theme that most people easily relate to. At the same time, landscape research has provided many appropriate tools for documenting landscape change and the effects of change. Yet in spite of public engagement and scientific knowledge, we still find many examples of negative landscape developments. In this paper we reflect on the applications of landscape research and the issue of communicating scientific findings to policy, management, landowners and the general public. Do we need a greater focus on communication to achieve sustainable landscape development?