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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.

2004

Abstract

Question: Does the understorey vegetation of Norwegian boreal forests change in relation to broad-scale, long-term changes? Location: Norway. Methods: Permanently marked 1-m2 vegetation plots from 17 monitoring reference areas in forests dominated by Picea abies (11 areas, 620 plots) and Betula spp. (six areas, 300 plots) were analysed twice, at the start in 1988-1997 and 5 yr later (1993-2002). Species subplot frequency data were analysed separately for each area by univariate and multivariate statistical methods; 5-yr changes in single species abundances, species number per plot and species composition were tested. Results: Two distinct patterns of change were found: Abundance of several vascular plant species decreased in SE Norwegian Picea forests, most noticeably of species with a preference for richer soils, such as Oxalis acetosella. Abundance of many bryophyte species as well as bryophyte species number per plot increased in forests of both types over most of Norway. Conclusions: The pattern of vascular plant changes is probably a time-delayed response of long-lived, mainly clonal, populations to acidified soils resulting from deposition of long-distance airborne pollutants. The pattern bryophyte changes, with reference to the close link between climatic conditions for growth and abundance changes for Hylocomium splendens established in previous demographic studies, is related to climatic conditions favourable for bryophyte growth. We conclude that many forest understorey plants are sensitive indicators of environmental change, and that the concept used for intensive monitoring of Norwegian forests enables early detection of changes in vegetation brought about by broadscale, regional, impact factors.

Abstract

Head-space sampling (HS) has been combined with enantioselective gas chromatography (GC) for the analysis of chiral and non-chiral monoterpenes present in the cortical tissues of five different Norway spruce clones. (1S)-()--Pinene, (1S,5S)-()sabinene, (1S)-()--pinene, and (4S)-()limonene dominated over (1R)-()--pinene, (1R,5R)-()-sabinene, (1R)-()--pinene, and (4R)-()-limonene.Results showed a large variation in the enantiomeric composition of cortical tissues between different clones. The development of HSGC greatly increased the speed of precise analyses of chiral monoterpenes in small samples and therefore offer excellent opportunities in studies on the ecophysiological and chemotaxomic roles of these chiral components