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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.

2012

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Abstract

Poland's share of private forests is relatively small compared with that of other European countries. Private Polish forests are in poor condition and have been under great economic stress. This situation has changed somewhat with respect to rural development since Poland's accession to the European Union. However, many antecedents to the innovativeness of forest owners remain unaddressed by scholars. The objective of this paper is to study the effect of forest owners' attitudes towards risk, social responsibility, learning orientation and institutional support on their innovativeness. Additionally, we aim to analyse the forest owners' attitudes towards start-ups based on nature-based tourism, which is a relatively new activity in Poland. We used both quantitative and qualitative approaches in this study and collected data via face-to-face interviews with 105 forest owners. The results showed that, although a forest owner's attitudes towards risk, social responsibility and learning orientation positively impacted the owner's innovativeness, institutional support did not. In the qualitative portion of this study, we examine nature-based tourism as a relatively new phenomenon and the factors affecting an owner's decision to initiate this type of business. The results imply that private forest owners in Poland require greater institutional support to start tourism businesses related to their forest land. However, the present support policies do not seem to have a direct positive effect on the forest owners' innovativeness. Nevertheless, policies that limit risk, promote learning and encourage social responsibility among Polish forest owners can stimulate them to become more innovative. Previous research has shown that this change, in turn, results in better economic performance and enhanced rural vitality.

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Abstract

Species spatial distributions are the result of population demography, behavioral traits, and species interactions in spatially heterogeneous environmental conditions. Hence the composition of species assemblages is an integrative response variable, and its variability can be explained by the complex interplay among several structuring factors. The thorough analysis of spatial variation in species assemblages may help infer processes shaping ecological communities. We suggest that ecological studies would benefit from the combined use of the classical statistical models of community composition data, such as constrained or unconstrained multivariate analyses of site-by-species abundance tables, with rapidly emerging and diversifying methods of spatial pattern analysis. Doing so allows one to deal with spatially explicit ecological models of beta diversity in a biogeographic context through the multiscale analysis of spatial patterns in original species data tables, including spatial characterization of fitted or residual variation from environmental models. We summarize here the recent progress for specifying spatial features through spatial weighting matrices and spatial eigenfunctions in order to define spatially constrained or scale-explicit multivariate analyses. Through a worked example on tropical tree communities, we also show the potential of the overall approach to identify significant residual spatial patterns that could arise from the omission of important unmeasured explanatory variables or processes. ecological community; multivariate spatial data; ordination; spatial autocorrelation; spatial connectivity; spatial eigenfunction; spatial structure; spatial weight.

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Abstract

Noninvasively collected genetic data can be used to analyse large-scale connectivity patterns among populations of large predators without disturbing them, which may contribute to unravel the species’ roles in natural ecosystems and their requirements for long-term survival. The demographic history of brown bears (Ursus arctos) in Northern Europe indicates several extinction and recolonization events, but little is known about present gene flow between populations of the east and west. We used 12 validated microsatellite markers to analyse 1580 hair and faecal samples collected during six consecutive years (2005–2010) in the Pasvik Valley at 70_N on the border of Norway, Finland and Russia. Our results showed an overall high correlation between the annual estimates of population size (Nc), density (D), effective size (Ne) and Ne ⁄Nc ratio. Furthermore, we observed a genetic heterogeneity of _0.8 and high Ne ⁄Nc ratios of _0.6, which suggests gene flow from the east. Thus, we expanded the population genetic study to include Karelia (Russia, Finland), Va¨sterbotten (Sweden) and Troms (Norway) (477 individuals in total) and detected four distinct genetic clusters with low migration rates among the regions. More specifically, we found that differentiation was relatively low from the Pasvik Valley towards the south and east, whereas, in contrast, moderately high pairwise FST values (0.91–0.12) were detected between the east and the west. Our results indicate ongoing limits to gene flow towards the west, and the existence of barriers to migration between eastern and western brown bear populations in Northern Europe.

Abstract

Light-emitting diodes (LEDs), high-pressure sodium lamps (HPSLs) and some cladding materials offer possibilities of influencing arthropod integrated pest management in greenhouse crops where light quality, quantity and photoperiod differ from nature. Light intensity, photoperiod and wavelength distribution affect plant functions and quality which, in turn, can be reflected in the performance of herbivores. The attenuation of UV-light in HPSL spectrum and in the natural winter daylight of northern latitudes may make plants more vulnerable to pests, whereas the high ratio of red to far-red of HPSLs may act to compensate for the effects of attenuated UV-levels. High red to far red ratio has been shown to result in increased production of plant phenolics and physical defences such as leaf toughness, which, in turn, can negatively influence the performance of some herbivore guilds on plants. Specific spectra produced by LEDs can influence plant quality and hence herbivore performance, but direct effects on arthropods can be even more pronounced, such as the inability to visually locat host plants in red and blue lights. Other direct effects of artificial light on pests and beneficial organisms include the detrimental effect of UV-C and UV-B on arthropods, diapause prevention by species-specific wavelengths or photoperiods, attraction to yellow-green and polarized light, reduced visibility of host or prey, and changes in take-off behaviour. Other effects include response to light intensity, interactive effects of light quality and photoperiod on fecundity, and species-specific effects of continuous light on the population growth of arthropods and plant-infesting fungi as well as the rhythmic expression of xenobiotic metabolising genes in arthropods. The potential of using the knowledge of photobiology and visual ecology of organisms for plant protection are discussed using whiteflies and fungal diseases of plants as the model species.