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.
2013
Authors
Nona S.R. Agawin Antonio Tovar-Sánchez Katrin Knoth Carlos M. Duarte Susana AgustiAbstract
No abstract has been registered
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Authors
Lars Qviller Nina Risnes Olsen Kim Magnus Bærum Erling Meisingset Leif Egil Loe Bjørnar Ytrehus Hildegunn Viljugrein Atle MysterudAbstract
No abstract has been registered
Authors
Celine Rebours Oddvar OttesenAbstract
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Authors
Alina Danielewska Elena Paoletti Nicholas Clarke Janusz Olejnik Marek Urbaniak Marcin Baran Pawel Siedlecki Karin Hansen Lars Lundin Wim de Vries Teis Nørgaard Mikkelsen Sophie Dillen Richard FischerAbstract
Aim of study: The main aim of the work was to summarize availability, quality and comparability of on-going European Research and Monitoring Networks (ERMN), based on the results of a COST FP0903 Action questionnaire carried out in September 2010 and May 2012. Area of study: The COST Action FP0903 involves 29 European countries and 4 non-COST institutions from USA, Morocco and Tunisia. In this study, the total of 22 replies to the questionnaire from 18 countries were included. Materials and methods: Based on the feedback from the Action FP0903 countries, the most popular European Networks were identified. Thereafter, the access to the network database, available quality assurance/quality control procedures and publication were described. Finally, the so-called “Supersites” concept, defined as a “highly instrumented research infrastructure, for both research and monitoring of soil-plant-atmosphere interactions” was discussed. Main results: The result of the survey indicate that the vast majority of the Action FP0903 countries participate in the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forest (ICP Forest). The multi-disciplinary International Cooperative Programme on Integrated Monitoring of Air Pollution Effects on Ecosystems (ICPIM) is the second most widespread forest programme. Research highlights: To fully understand biochemical cycles in forest ecosystems, long-term monitoring is needed. Hence, a network of “Supersites”, is proposed. The application of the above infrastructure can be an effective way to attain a better integration of research and monitoring networks at forest sites in Europe. Key words: supersites; European Research Monitoring Networks; harmonization; forest.
Authors
May Sæthre F. Assogba Komlan Nina Svendsen Børge Holen I. GodonouAbstract
No abstract has been registered
Authors
Daniel Flø Sigmund HågvarAbstract
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Authors
Lampros LamprinakisAbstract
Changes in the institutional and market environments can present new challenges for organizations. The ability to properly and adequately change and adapt to these new conditions can be crucial for organizations’ competitiveness and their long-term survival. The article offers a qualitative case study analysis on the transformation process of the biggest Finnish dairy organization, Valio, in the light of the country’s accession to the EU. The analysis is based on thirteen personal in-depth semi-structured interviews with management employees, executives, past directors and industry insiders. The examination covers several aspects of the organization’s efforts to adapt with a particular focus on processes, strategies, and transition stages, and thus provides invaluable insight that allows the better understanding of a successful transformation.
Abstract
Modelling stem taper and volume is crucial in many forest management and planning systems. Taper models are used for diameter prediction at any location along the stem of a sample tree. Furthermore, taper models are flexible means to provide information on the stem volume and assortment structure of a forest stand or other management units. Usually, taper functions are mean functions of multiple linear or nonlinear regression models with diameter at breast height and tree height as predictor variables. In large-scale inventories, an upper diameter is often considered as an additional predictor variable to improve the reliability of taper and volume predictions. Most studies on stem taper focus on accurately modelling the mean function; the error structure of the regression model is neglected or treated as secondary. We present a semi-parametric linear mixed model where the population mean diameter at an arbitrary stem location is a smooth function of relative height. Observed tree-individual diameter deviations from the population mean are assumed to be realizations of a smooth Gaussian process with the covariance depending on the sampled diameter locations. In addition to the smooth random deviation from the population average, we consider independent zero mean residual errors in order to describe the deviations of the observed diameter measurements from the tree-individual smooth stem taper. The smooth model components are approximated by cubic spline functions with a B-spline basis and a small number of knots. The B-spline coefficients of the population mean function are treated as fixed effects, whereas coefficients of the smooth tree-individual deviation are modelled as random effects with zero mean and a symmetric positive definite covariance matrix. The taper of a tree is predicted using an arbitrary number of diameter and corresponding height measurements at arbitrary positions along the stem to calibrate the tree-individual random deviation from the population mean estimated by the fixed effects. This allows a flexible application of the method in practice. Volume predictions are calculated as the integral over cross-sectional areas estimated from the calibrated taper curve. Approximate estimators for the mean squared errors of volume estimates are provided. If the tree height is estimated or measured with error, we use the “law of total expectation and variance” to derive approximate diameter and volume predictions with associated confidence and prediction intervals. All methods presented in this study are implemented in the R-package TapeR.
Authors
Peder Gjerdrum Birger EikenesAbstract
Strength properties are central for most wood applications. This paper describes variation of and co-variation between various strength parameters observed in clear wood. More than a dozen strength and density parameters were measured, each on ten samples from five different height levels from each of 21 planted, mature spruce trees. In general, strength and coefficient of variation comply with standard listed values. Between strength parameters usually modest, but always positive, correlation was found. Only 53% of the overall strength variation could be extracted in the first principal component, related to density. MOE and MOR are the two most closely correlated traits, and cleavage the one to show weakest connection to all other traits. Compression, MOR and hardness are closest correlated to density; however, the significance of density being partially masked by a considerable variation between samples from similar locations in the stem supposed to demonstrate parallel quality. All traits are stronger correlated to density than to ring width. In addition to density a substantial part, 5 to 30%, of strength variation could be attributed to tree effect, indication a potential for strength improvement by genetic selection. The finding confirms strength parameters to be far from collinear, i.e. strength is truly multidimensional.