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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.

2016

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Abstract

Riverine inputs and direct discharges to Norwegian coastal waters in 2015 have been estimated in accordance with the OSPAR Commission’s principles. Nutrients, metals and organic pollutants have been monitored in rivers; discharges from point sources have been estimated from industry, sewage treatment plants and fish farming; and nutrient inputs from diffuse sources have been modelled. Trends in riverine inputs have been analyzed, and threshold concentration levels investigated.

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Abstract

The use of seaweeds in animal diets is not new. However, little is known about the feed value of seaweed, both in terms of chemical composition and protein digestibility, and regarding variation between species and season. In this study, eight seaweed species of the genus Acrosiphonia, Alaria, Laminaria, Mastocarpus, Palmaria, Pelvetia, Porphyra, and Ulva were sampled in spring (March) and autumn (October and November) 2014 at the coast of Bodø in Northern Norway, and were analysed for chemical composition, in situ rumen degradability and total tract crude protein (CP) digestibility. Ash content in dry matter (DM) was generally high (overall mean 190 g/kg in DM) and varied considerably, between species (P < 0.01) and between seasons (P = 0.02). CP concentration in DM varied both between species (P < 0.0001) and seasons (P < 0.01). Highest CP in DM was found for Porphyra (350 g/kg DM) and lowest for Pelvetia (90 g/kg DM). Spring samples were higher in CP than autumn samples. The effective degradability estimated at 5% rumen passage rate (ED5) of CP varied between species (P < 0.0001) but not between seasons (P = 0.10). The highest ED5 of CP was found for Alaria (550 g/kg CP) and lowest for Ulva (240 g/kg CP). Digestible rumen escape protein (DEP) varied significantly between species (P < 0.0001) but not between seasons (P = 0.06); highest DEP was found for Ulva (530 g/kg CP) and Porphyra (500 g/kg CP). Based on our results, Acrosiphonia, Alaria, Laminaria, Mastocarpus and Palmaria can supply the rumen with high amounts of rumen degradable protein, while Porphyra and Ulva can be used as a source of digestible bypass protein. Pelvetia had a very low degradability and should not be used to feed dairy cows.

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Abstract

Top dieback of Norway spruce (Picea abies), triggered by drought in 2004–2006, has been observed in Southeast Norway and trees died within four years after appearance of the first symptoms. The aim of our study was to use sap flux measurements as a diagnostic method for assessment of tree vitality. We used the heat field deformation method to monitor the sap flux density (SFD) in four pairs of healthy and declining trees in situ. To provide retrospective information on hydraulic performance of the trees we took samples for wood anatomical analysis. After felling the trees we used the modified differential translucence method (MDT) as a proxy for the SFD measurements. Healthy trees had three times higher SFD values as declining trees. In some healthy trees we detected decreasing SFD with time. The MDT method agreed with the SFD measurements. In conclusion, we detected sap flux dysfunction in declining trees and showed that the SFD reduction may occur during a short period, prior to occurrence of any visual symptoms. We suggest incorporating the SFD measurements into the repertoire of diagnostic tools in forest pathology.

Abstract

Grasslands are significant as a source of forage for animal production, but are also important in many ecological functions. To be able to analyse changes in environmental conditions of grasslands, monitoring of grassland areas using remote sensing is an important task. Studying changes in environmental condition over time and space in grasslands has been the subject of research at different scales. Such an example is the Polish-Norwegian Research Project FINEGRASS „Effect of climatic changes on grassland growth, its water conditions and biomass’. In situ measured soil-vegetation parameters and satellite observations have been combined and analysed to quantify the spatial and temporal variability of grassland conditions, as reflected in variations of vegetation surface temperature, soil moisture, and biomass. Results show a significant trend of increasing grassland surface temperature in Poland, based on AVHRR satellite data; a positive significant relationship between the (April-September) standardized precipitation evapotranspiration index (SPEI) and grass yields in Poland; northern Norway has shown trends towards warmer springs and autumns since 1991, and significant trends towards earlier snowmelt and green-up on test fields in northern Norway.

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Abstract

Two new species of Schistidium are described from Asian Russia. Their distinctness is supported by nrDNA ITS1-2 sequence data. S. austrosibiricum was not previously differentiated from S. sinensi- apocarpum, mainly due to their similarly long and sharply serrate hair-points in stem and perichaetial leaves and papillose dorsal side of costa. However, they differ in leaf size and shape, hair-points flatness and leaf lamina areolation. S. austrosibiricum is known from southernmost mountain areas of Asian Russia, while S. sinensiapocarpum is a widespread circumholarctic montane species. The sec- ond species, S. scabripilum is morphologically similar to S. echinatum, and some specimens were previously referred to it. The main differences between them concern hair-point length and structure, including length of protruding spinulae and their angle with the hair-point axis. However, they belong to different clades in the molecular phylogenetic tree and possess different distribution patterns. S. scabripilum is a northern Asian species, found in the Putorana Plateau, southern Taimyr, Yakutia and Chukotka, while S. echinatum is known from the Alps, Caucasus and Ural mountains, and in western North America. Description, illustrations, distribution and ecological data are provided for the new species, and comparison with similar species is given.