Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2018
Sammendrag
Miljøpåvirkning av tre sammenlignet med andre bygningsmaterialer Den norske regjeringen har satt klare mål for å redusere forbruket av fossil energi og klimagassutslipp. Byggsektoren kan bidra for å nå disse målene ved å: Bygge energieffektive bygg; Bruke materialer med lavt forbruk av grå energi (low embodied energy materials); Bruke byggematerialer som lager for atmosfærisk karbondioksid.
Forfattere
Fride Høistad ScheiSammendrag
Det er ikke registrert sammendrag
Forfattere
Fride Høistad ScheiSammendrag
Det er ikke registrert sammendrag
Sammendrag
This paper presents an optimization model designed to find productivity functions for timber forwarding. Timber forwarding or skidding has for some 25 years been calculated using shortest path formulations on grid networks. Unfortunately, few productivity studies relate to such grids. Here, an inverse shortest path problem is presented, basically panning out costs on the grid based on point cost estimates. The formulation is tested using point cost estimates from the national forest inventories of Norway, together with a terrain model and other public spatial data (e.g. roads, water). The problem is optimized using the metaheuristic variable neighborhood search. The results of the test cases were achieved in reasonable time, and indicate that part of the solution space might be convex. The productivity function found for one of the test cases was used to create a variable forwarding cost map of the case area.
Forfattere
Kris Verheyen Martin Bažány Ewa Chećko Markéta Chudomelová Déborah Closset-Kopp Patryk Czortek Guillaume Decocq Pieter De Frenne Luc De Keersmaeker Cecilia Enriquez Garcia Martina Fabšičová John-Arvid Grytnes Lucia Hederová Radim Hédl Thilo Heinken Fride Høistad Schei Soma Horváth Bogdan Jaroszewicz Edyta Jermakowicz Terezá Klinerova Jens Kolk Martin Kopecký Iwona Kuras Jonathan Lenoir Martin Macek František Máliš Tone Constance Martinessen Tobias Naaf László Papp Ágnes Papp-Szákaly Paweł Pech Petr Petřík Jindřich Prach Kamila Reczýnska Magne Sætersdal Fabien Spicher Tibor Standovár Krzysztof Świerkosz Ewa Szczęśniak Zoltán Tóth Karol Ujházy Mariana Ujházyová Pieter Vangansbeke Ondřej Vild Dan Wołkowycki Monika Wulf Lander BaetenSammendrag
Aim: Revisits of non-permanent, relocatable plots first surveyed several decades ago offer a direct way to observe vegetation change and form a unique and increasingly used source of information for global change research. Despite the important insights that can be obtained from resurveying these quasi-permanent vegetation plots, their use is prone to both observer and relocation errors. Studying the combined effects of both error types is important since they will play out together in practice and it is yet unknown to what extent observed vegetation changes are influenced by these errors. Methods: We designed a study that mimicked all steps in a resurvey study and that allowed determination of the magnitude of observer errors only vs the joint observer and relocation errors. Communities of vascular plants growing in the understorey of temperate forests were selected as study system. Ten regions in Europe were covered to explore generality across contexts and 50 observers were involved, which deliberately differed in their experience in making vegetation records. Results: The mean geographic distance between plots in the observer+relocation error data set was 24 m. The mean relative difference in species richness in the observer error and the observer+relocation data set was 15% and 21%, respectively. The mean “pseudo-turnover” between the five records at a quasi-permanent plot location was on average 0.21 and 0.35 for the observer error and observer+relocation error data sets, respectively. More detailed analyses of the compositional variation showed that the nestedness and turnover components were of equal importance in the observer data set, whereas turnover was much more important than nestedness in the observer+relocation data set. Interestingly, the differences between the observer and the observer+relocation data sets largely disappeared when looking at temporal change: both the changes in species richness and species composition over time were very similar in these data sets. Conclusions: Our results demonstrate that observer and relocation errors are nonnegligible when resurveying quasi-permanent plots. A careful interpretation of the results of resurvey studies is warranted, especially when changes are assessed based on a low number of plots. We conclude by listing measures that should be taken to maximally increase the precision and the strength of the inferences drawn from vegetation resurveys.
Forfattere
Anders Arvesen Francesco Cherubini Gonzalo del Alamo Serrano Rasmus Astrup Michael Becidan Helmer Belbo Franziska Goile Tuva Grytli Geoffrey Guest Carine Lausselet Per Kr. Rørstad Line Rydså Morten Seljeskog Øyvind Skreiberg Veena Sajith Vezhapparambu Anders Hammer StrømmanSammendrag
Climate impacts of forest bioenergy result from a multitude of warming and cooling effects and vary by location and technology. While past bioenergy studies have analysed a limited number of climatealtering pollutants and activities, no studies have jointly addressed supply chain greenhouse gas emissions, biogenic CO2 fluxes, aerosols and albedo changes at high spatial and process detail. Here, we present a national-level climate impact analysis of stationary bioenergy systems in Norway based on wood-burning stoves and wood biomass-based district heating. We find that cooling aerosols and albedo offset 60–70% of total warming, leaving a net warming of 340 or 69 kg CO2e MWh−1 for stoves or district heating, respectively. Large variations are observed over locations for albedo, and over technology alternatives for aerosols. By demonstrating both notable magnitudes and complexities of different climate warming and cooling effects of forest bioenergy in Norway, our study emphasizes the need to consider multiple forcing agents in climate impact analysis of forest bioenergy.
Sammendrag
Forestry in coastal Norway has traditionally been a marginal activity with a low annual harvest rate. However, the region is now faced with large areas of spruce plantations that will reach harvest maturity within the next 25 years. Due to the poor infrastructure in the region, the current challenge is to harvest the maturing spruce plantations at an acceptable cost. Hence, there is considerable interest both from the forest sector and politicians to invest in infrastructure that can provide the basis for profitable forest sector development in coastal Norway. This paper presents a mathematical optimization model for timber transportation from stump to industry. The main decision variables are location of quays, upgrade of public road links, the length of new forest roads, and when the investments should happen. The main objective is to provide decision support for prioritization of infrastructure investments. The optimization model is combined with a dynamical forest resource model, providing details on available volumes and costs. A case study for coastal Norway is presented and solved to optimality. The instance includes 10 counties comprising more than 200 municipalities with forest resources, 53 possible new quays for timber export and 916 public road links that also can be upgraded. Compared with a no investment case, the optimal solution improved the objective by 23%. The study shows that consistent, informative and good analyses can be performed to evaluate trade-offs, prioritization, time and order of investment, and cost saving potentials of infrastructure investments in the forest industry. The solution seems reasonable based on present infrastructure and state of the forest.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Andreas Treu Katrin Zimmer Christian Brischke Erik Larnøy Lone Ross Foued Aloui Simon M Cragg Per Otto Flæte Miha Humar Mats Westin Luisa M. S. Borges John WilliamsSammendrag
Det er ikke registrert sammendrag
2017
Sammendrag
Denne rapporten er utarbeidet som avslutning av prosjektet «Forprosjekt – Markfuktighetskart for skogen i Norge». Eier av prosjektet har vært Norges Skogeierforbund og NORSKOG. Faglig ansvarlig har vært NIBIO ved forsker Jan Bjerketvedt. Skogkurs har hatt prosjektansvaret og stått for gjennomføringen. Prosjektet er finansiert med støtte fra Skogtiltaksfondet. I tillegg har NIBIO og Skogkurs gått inn med egne midler.