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
Sammendrag
No abstract has been registered
Forfattere
David Bredström Petrus Jönsson Mikael RönnqvistSammendrag
A cost-efficient use of harvesting resources is important in the forest industry. The main planning is carried out in an annual resource plan that is continuously revised. The harvesting operations are divided into harvesting and forwarding. The harvesting operation fells trees and puts them in piles in the harvest areas. The forwarding operation collects piles and moves them to storage locations adjacent to forest roads. These operations are conducted by machines (harvesters, forwarders and harwarders), and these are operated by crews living in cities/villages that are within some maximum distance from the harvest areas. Machines, harvest teams and harvest areas have different characteristics and properties and it is difficult to find the best possible match throughout the year. The aim of the planning is to find an annual plan with the lowest possible cost. The total cost is based on three parts: production cost, traveling cost and moving cost. The production cost is the cost for the harvesting and forwarding. The traveling cost is the cost for driving back and forwards (daily) from the home base to the harvest area and the moving cost is associated with moving the machines and equipment between harvest areas. The Forest Research Institute of Sweden (Skogforsk), together with a number of Swedish forest companies, has developed a decision support platform for the planning. One important element of this platform is that it should find high-quality plans within short computational times. One central element is an optimization model that integrates the assignment of machines to harvest areas and schedules the harvest areas during the year for each machine. The problem is complex and we propose a two-phase solution method where, first, we solve the assignment problem and, second, the scheduling. In order to be able to control the scheduling in phase 1 as well, we have introduced an extra cost component that controls the geographical distribution of harvest areas for each machine in phase 1. We have tested the solution approach on a case study from one of the larger Swedish forest companies. This case study involves 46 machines and 968 harvest areas representing a log volume of 1.33 million cubic meters. We describe some numerical results and experience from the development and tests.
Sammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Forfattere
Bringas Carlos M. Salas Tore Filbakk Geir Skjevrak Odd-Ivar Lekang Olav Høibø Reidar Barfod SchüllerSammendrag
No abstract has been registered
Sammendrag
No abstract has been registered
Sammendrag
Norwegian agriculture is mainly dominated by grass-based milk and livestock production, so winter damage to overwintering grasses may have large economic consequences. We assessed the impact of climate change on the winter survival of timothy (Phleum pratense L) and perennial ryegrass (Lolium perenne L) under Norwegian conditions using agroclimatic indices and a simulation model of frost tolerance. This study was based on locally adjusted future climate scenarios (two for the period 2071-2100; one for the period 2020-2049) for six important agricultural regions, represented by one location each. We proposed and validated a rough way to estimate the daily minimum air temperatures from scenario data. compared with the control period 1961-1990, the future hardening period will be shortened by up to 21 days. As a consequence, the modelled maximum frost tolerance is expected to be reduced by up to 3.9 degrees C and 1.9 degrees C for timothy and perennial ryegrass, respectively, under the warmest scenario. In spite of this reduction, the plants are expected to be hardy enough to withstand the predicted autumn frosts, and we also expect a general reduction in the risk of winter frost injuries. The plant data available to this study suggest that agroclimatic indices developed for Canadian conditions can be useful for assessing the hardening status in timothy and perennial ryegrass. However, such indices are less suitable for assessing the risk of plant injury related to frost and ice encasement in Norway, since they do not account for the dynamics of cold adaptation. Although less snow is expected, in most cases this will not be accompanied by an increase in the risk of ice encasement injuries. However, a slight increase in the number of ice encasement events was predicted for one location. An earlier start of growth was predicted for all locations, accompanied at one coastal location by a slightly increased predicted risk of spring frosts. There is little risk of winter injuries related to frost and ice encasement in the hardier grass species timothy. The better overwintering conditions in general indicate that it will be possible to grow perennial ryegrass in areas where it is not grown today, provided the risk of fungal diseases does not increase. (C) 2010 Elsevier B.V. All rights reserved.
Forfattere
May Sæthre Ignace Godonou Segolene Leclerq Ghislain Tchoromi Tepa-Yotto Braima JamesSammendrag
No abstract has been registered
Forfattere
Jens Rohloff Inger Martinussen Eivind Uleberg Olavi Junttila Anja Hohtola Laura Jaakola Hely HäggmanSammendrag
The fruit quality of European blueberry (EB) is mainly determined by taste compounds (sugars, acids, flavour) and health-beneficial structures generally denoted as antioxidants (vitamin C, phenolic acids, flavonols, anthocyanins, proanthocyanidins). Content and compound composition is strongly affected by the growth environment regarding light, temperature, water and edaphic factors. In order to assess genotypic relationships (northern and southern clones of EB) and environmental impact (temperature, day length) on berry quality parameters, a high-throughput system for blueberry metabolite profiling of nutritional compounds was established based on gas chromatography coupled with mass spectrometry (GC/MS). Dried methanol/H2O extracts from fresh-frozen berry tissue were derivatized, and subjected to GC/MS in order to detect polar compounds such as organic acids from Krebs-cycle, amino acids, sugars, polyols, and partly secondary metabolites (phenols, flavonoids). In addition, general quality parameters such as total phenols, total anthocyanins and antioxidant capacity (FRAP) were measured. Fructose (5 g), glucose (5 g), and sucrose (0.5 g/ 100 g f.w. at average) were the most abundant carbohydrates, together with high levels of organic acids such as citric acid (1.3 g), quinic acid (1.6 g), and malic acid (0.3 g/ 100 g f.w. at average). More than 50 metabolites per sample (identified compounds and not-annotated mass spectral tags) could be detected, and established the basis for multivariate statistics using principal component analysis, hierarchical clustering, and metabolite network analysis. Genotypic differences, modulation of metabolite pools and biosynthetic relationships are being discussed in-depth.
Forfattere
Aldo Marchetto Rosario Mosello Gabriele A. Tartari Kirsti Derome Nils König Nicholas Clarke Anna KowalskaSammendrag
A second Working Ring Test (WRT) was organised within the framework of the EU/Life+ FutMon Project (`Further Development and Implementation of an EU-level Forest Monitoring System`, LIFE07 ENV/D/000218), to evaluate the overall performance of the laboratories responsible for analysing atmospheric deposition and soil solution samples in European forests, and to verify improvements in the analytical quality resulting from the QA/QC work carried out in the laboratories which participated in previous WRTs organized in the framework of the UN/ECE ICP Forests Monitoring Programme. The WRT was carried out in accordance with International ISO and ILAG guide proficiency test both for sample preparation and numerical elaboration of the results. Five natural atmospheric deposition and soil solution samples and 3 synthetic solutions were distributed to 42 laboratories for analysis using their routine methods for the following variables: pH, conductivity, calcium, magnesium, sodium, potassium, ammonium, sulphate, nitrate, chloride, total alkalinity, total dissolved nitrogen (TDN), dissolved organic carbon (DOC). Two tolerable limits were defined for each variable on the basis of the measured value, the results of previous WRTs, a comparison with the Data Quality Objectives of other international networks, and the importance of the variable in deposition and soil solution monitoring. In the ring test 12% of the results from all the laboratories did not fall within the tolerable limits. This enabled us to identify those variables and laboratories for which improvements in analytical performance are required. The results of the exercise clearly show that the use of data check procedures, as described in the ICP Forests manual for sampling and analysis of atmospheric deposition, makes it possible to detect the presence of inaccurate or outlying results, and would therefore greatly improve the overall performance of the laboratories. A discussion of the improvement of the results in this WRT compared to the previous WRTs is also included, showing a relevant improvent for several variables and underlining the importance of participating to these exercises for the overall analytical quality of the monitoring network.