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.
2001
Authors
Alf Bakke Leif Aarvik K. BerggrenAbstract
No abstract has been registered
Authors
Rolf D. Vogt K. Bishop Nicholas Clarke T.C. Gadmar E.T. Gjessing Jan Mulder Michael Starr Dag Olav AndersenAbstract
The main tasks of the NOMiNiC project (Natural Organic Matter in the Nordic countries; see http://www.kjemi.uio.no/envir/nominic/) is to study the physiochemical characteristics of dissolved organic matter (DOM) and provide reverse osmosis (RO) spring and fall isolates of surface water natural organic matter (NOM) from 5 Nordic forested sites that differ mainly in atmospheric S-loading and climate. Hydrophobic and hydrophilic fractions are hypothesized to be more easily defined and have distinct different chemical characteristics than the total sample. A XAD-8 fractionation may then be used as a simple proxy for the physico-chemical properties of NOM. Both XAD-8 fractions and the total DOM sample have been base and metal titrated. Enhanced understanding of the significance of the numerous operationally defined parameters describing NOM will be achieved through a common multi-dimensional characterisation of the same set of isolates, that span a large spectre of the variation found in DOM. 7 institutes are already collaborating in characterizing the RO isolates using a large range of techniques and new participants are invited. In this presentation the 5 sampling sites are described and some results of the characterisation of the RO isolates are presented.
Abstract
Air pollution induced changes in pine needle chemistry were observed at sample sites in the surroundings of the Pechenganikel smelter. Close to the smelter, elevated concentrations of Ni, Cu and S were found (Ni: 0.7-1 mmol/kg, CU: 0.4-0.5, and S 40-60 mmol/kg) Close to the pollution source needles were enriched in Ni and Cu by needle age. Correlation and principal component analyses show that changes in the element composition of pine needles depended on air pollution and on natural factors as well. The contribution from air pollution increased with needle age. Besides direct input of pollutants from atmosphere, soil contamination and nutritional disturbance contributed significantly to the observed changes.
Authors
Jenny Fäldt Halvor Solheim Bo Långström Anna-Karin Borg-KarlsonAbstract
No abstract has been registered
Authors
I. Lofstrom Vegard Gundersen Bernt-Håvard Øyen B.B. JørgensenAbstract
No abstract has been registered
Authors
Heleen A. de Wit T. Groseth Jan MulderAbstract
No abstract has been registered
Authors
Oddvar SkreAbstract
Direct and indirect effects of increased CO2 level on the mountain birch ecosystem are reviewed and evaluated, and supplemented with some case studies on mountain birch (Betula pubescens) based on field experiments at different altitudes and greenhouse experiments at elevated CO2 and winter temperature level. These studies have shown that large differences exist in responses on climate change between mountain birch populations, and that these differences may be related to the climate at their habitat.
Authors
Halvor TorgersenAbstract
Excavator based harvesters for mechanisation in steep terrain, on tracks or wheels?
Authors
Peder GjerdrumAbstract
Sawmill recovery might be improved by pre-conversion sorting of logs to obtain more homogenous timber quality suitable for specified products. To enhance the knowledge of factors influencing timber quality, 670 spruce trees from 11 mature stands were observed during harvesting and timber processing. By means of factor analysis several knot and resin pocket properties were reduced to two principal components, one representing the knots and another for resin pockets. The number of independent variables are not easily reduced, leaving a possibility of applying several of the characteristics of the logs, the trees and of the stands in finding an efficient log sorting algorithm.
Abstract
No abstract has been registered