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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.

2010

Abstract

Norway spruce (Picea abies [L.] Karst.), one of the most important species of the boreal forest, is found naturally distributed in two disjunct ranges; one northern and one southern European range. These ranges have been shown to correspond to two genetically distinct lineages. In this talk, results on the genetic structure based on mitochondrial DNA (mtDNA; nad1) and nuclear microsatellites in populations from the northern European lineage, will be presented and discussed in the light of its glacial and postglacial history. The genetic relationship between Norway spruce and its will closest relative Siberian spruce (Picea abovata Lebed.) will also be discussed based on results from mtDNA and paternally inherited chloroplast DNA (cpDNA). Genetic structure of northern European Norway spruce is generally shallow, consistent with recently compiled pollen data, suggesting that Norway spruce in Northern Europe was colonized from a single Russian refugium. Despite the low differentiation found, the structure at both mtDNA and nuclear DNA suggest that expansion westwards took place along two main migration routes; one northwestern over Finland to northern Scandinavia, and one southwestern across the Baltic Sea into Scandinavia. Based on both mtDNA and nuclear DNA, populations in the oldest regions of Russia and the Baltic States show the highest diversity. Based on pollen data, colonization of these regions took place at high population densities, helping to maintain high levels of diversity. Also populations in southern Sweden and southern Norway show relatively high levels of diversity compared to the more northern Scandinavian populations. This may be due to the additional southern migration route into the region, as well as pollen-mediated gene flow in the south which seems to efficiently have replenished the loss of nuclear diversity following postglacial colonization. In the northern part of Fennoscandia, smaller effective population size due to more limited seed and pollen production may have caused decreased nuclear diversity and increased inbreeding, reflecting the ecological marginality of the species in the north. Genetic differentiation between Norway spruce and Siberian spruce based on mitochondrial and chloroplast markers suggest that the border between the two species occur east of the Ural Mountain, following the river Ob. Still, the paternally inherited cpDNA marker suggests extensive introgression from Siberian spruce into the northern European range of Norway spruce. Introgression via pollen may thus acts as a mechanism of dispersal of Siberian spruce genes into the northern European gene pool of Norway spruce.

Abstract

The genome H. annosum s.l. was sequenced by JGI to a 8.23X coverage and assembled into 39 scaffolds with a total size of 33.7 Mb covering more than 98% of the whole genome. Based of genome sequence we annotated a number of genes for fungal enzymes that are believed to participate in lignin degradation, including: laccases (Lcc18 genes), manganese peroxidases (MnP8 genes) and hydrogen peroxide forming enzymes such as glyoxal oxidases (GLOX5 genes), quinone oxidoreductases (QOR17 genes) and aryl alcohol oxidases (AAO16 genes), which is in concordance with these gene family sizes observed in other sequenced white-rot fungi. We studied the genomic organisation and phylogeny of these genes as well as their expression using NimbleGen arrays and qRT-PCR. Transcript profiling using whole-genome oligo arrays and qRT-PCR revealed that some transcripts were very abundant in lignin-rich media (Lcc5 15, MnP2, GLOX4, QOR2 10, AAO9), in cellulose-rich media (lcc2, 7 16, MnP3 4, GLOX3, QOR4 6, AAO2, 7 10), in wood (Lcc3, MnP4, QOR2, GLOX1, AAO10) or in the free-living mycelium grown liquid culture (Lcc1, 3, 10 13), suggesting specific functions of these genes, which need to be studied further.

Abstract

Understanding the feedback between terrestrial biosphere processes and meteorological drivers is crucial to ecosystem research as well as management. For example, remote sensing of the activity of vegetation in relation to environmental conditions provides an invaluable basis for investigating the spatiotemporal dynamics and patterns of variability. We investigate the Fraction of Absorbed Photosynthetically Active Radiation (fAPAR) using SeaWiFS satellite observations from 1998 to 2005 and ancillary meteorological variables from the CRU-PIK dataset. To what extent do precipitation and temperature dominate the terrestrial photosynthetic activity on monthly to interannual time scales? A spectral decomposition using Singular System Analysis leads to a global ‘classification’ of the terrestrial biosphere according to prevalent time-scale dependent dynamics of fAPAR and its relation to the meteorology. A complexity analysis and a combined subsignal extraction and dimensionality reduction reveals a series of dominant geographical gradients, separately for different time scales. Here, we differentiate between three time scales: on short time scales (compared to the annual cycle), variations in fAPAR coincide with corresponding precipitation dynamics. At the annual scale, which explains around 50% of the fAPAR variability as a global average, patterns largely resemble the biomes of the world as mapped by biogeographic methods.At longer time scales, spatially coherent patterns emerge which are induced by precipitation and temperature fluctuations combined. However, we can also identify regions where the variability of fAPAR on specific time scales cannot be traced back to climate and is apparently shaped by other geoecological or anthropogenic drivers. http://uregina.ca/prairies/assets/Prairie_Summit_Final_Program.pdf

Abstract

Determining the feedbacks between terrestrial biosphere processes and the meteorological drivers (here precipitation and temperature) is crucial to ecosystem research. In this context, the continuous monitoring of the earth surface provides an invaluable basis for investigating the spatiotemporal dynamics in the activity of vegetation in relation to environmental conditions. Here, we seek to identify which patterns of variability in the meteorological drivers dominate the terrestrial photosynthetic activity from monthly to interannual time scales (resp. fluctuation frequencies). We investigate the Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) using SeaWiFS observations from 1998 to 2005 and ancillary meteorological variables. A spectralanalysis leads to a global `classification` of the terrestrial biosphere according to prevalent scale dependent dynamics of fAPAR and its relation to the meteorology. A combined subsignal extraction and dimensionality reduction reveals a series of dominant geographical gradients on specific time scales. E.g. we uncover spatially coherent patterns at low frequencies and show where these are induced by precipitation or temperature fluctuations. We also show where high frequency variations (relative to the annual cycle) in fAPAR coincide with corresponding precipitation dynamics. However, we can also identify regions where the variability of fAPAR on specific time scales cannot be traced back to climate and is apparently shaped by other geoecological or anthropogenic drivers. http://www.terrabites.net/fileadmin/user_upload/terrabites/PDFs/Programme_Book_TERRABITES.pdf

Abstract

A number of presentations were given at the GlueLam Study Tour in Trøndelag arranged by The Norwegian Forest and Landscape Institute April 2010 within the Developing the Scots Pine Resource project. The editor wishes to express his gratitude to all those who contributed to the outcome of the study tour: To the host businesses, to the participants and those giving presentations, and to Northern Periphery Program for contributing to the funding. The presentations listed in this report has been collected, trimmed and otherwise slightly modified by the editor. However, the content as well as the layout have been the choice and responsibility of each author. The report is intended for publication in electronic format on the project\"s web page and distribution to the participants. However, the report is public and free to use for anybody, provided a proper citation is given.