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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.

1999

Abstract

Arthothelillm lirellans and A. orbilliferum are reported new to Scandinavia. Both species were found in Hordaland, western Norway. Their ecology and European distribution are discussed, and distribution maps presented.

Abstract

The complex character of variations in acidity and cation exchange properties of forest podzols under the impact of atmospheric emissions from Pechenganikel plant in the Kola Peninsula was revealed using correlation and regression analyses. The high level of acidity and the depletion of upper horizons in exchangeable bases attest for the anthropogenic acidification of podzols in the affected zone of the plant.

Abstract

The area along the Norwegian-Russian border is threatened by air pollution from emission sources on the Kola Peninsula. A permanent network of 78 systematically chosen monitoring sites has been established in eastern Finnmark, Norway. Species abundance data from the ground vegetation have been recorded from 1320 systematically chosen permanent plots inside 66 of these sites, using frequency in subplots and visual estimates of percentage cover. Environmental variables were obtained for the whole site. Multivariate data analysis has been used to describe the variation in the species composition and to study its relation to environmental variables and pollution impact. The analyses show that much of the variation in the species composition, based on average species abundance at the sites, is well explained by different soil and climatic conditions. However, estimated SO2 deposition, Ni, and Cu in the soil, and Ni in Cladina tissue have also been found to be statistically significantly correlated with the variation in the species data, but they explain only a minor part of the variation. The pollution impact over several years may have lead to a reduced lichen cover in the bottom-layer vegetation. Further development in an either negative or positive direction can be detected by re-investigations of the monitoring sites.

Abstract

The vegetation of traditionally managed species-rich hay meadows at Sverveli, Telemark, S Norway was studied applying an indirect gradient approach. The vegetation in 93 randomly placed sample plots was analysed in order to detect the main vegetational gradients. Ecological measurements were recorded from each plot. The relationships between vegetation and environment were studied by DCA and LNMDS ordinations and non-parametric correlation analysis. Both ordinations revealed the same two ecologically interpretable vegetation gradients. Soil moisture was identified as the most important environmental factor in determining the species composition, followed by soil nutrient content. The contents of P, K and Mg in the soil were more strongly correlated with the main vegetational gradients than was soil N.Differences in management history may explain some of the observed variation in species composition that was not accounted for by the recorded environmental variables.

Abstract

Winter dormancy reduces or inhibits totally the growth ability of buds. Dormancy release and budburst in Scandinavian Betula pendula Roth. and B. pubescens Ehrh. ecotypes were studied in controlled environments. There was a gradual decline in the heat-sum requirement for budburst with increasing chilling time. Two main clines in time of dormancy release appeared in ecotypes of different geographic origin, a latitudinal cline and a coastal-inland cline in which the duration of dormancy increased southwards and towards the coast. In addition, dormancy was later alleviated in high-altitude than in lowland B. pubescens ecotypes. In late autumn, after 44 chilling days, time to budburst at 15C was less in plants chilled at 0C than in plants chilled at 10C, indicating that 0C was most effective for dormancy release. In January, after 105 chilling days, however, dormancy release was completed, and budburst was earliest in plants chilled at 10C. At this stage there were no detectable differences in effectiveness between fluctuating and corresponding constant temperatures (6 to 21C) in promoting growth and budburst in B. pubescens. Long photoperiods significantly reduced time to budburst in partly dormant buds, but had no effect when dormancy was fully released

1998