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.
2017
Forfattere
Lorenzo Marini Bjørn Økland Anna Maria Jönsson Barbara Bentz Allan Carroll Beat Forster Jean-Claude Grégoire Rainer Hurling Louis Michel Nageleisen Sigrid Netherer Hans Peter Ravn Aaron Weed Martin SchroederSammendrag
Bark beetles are among the most devastating biotic agents affecting forests globally and several species are expected to be favored by climate change. Given the potential interactions of insect outbreaks with other biotic and abiotic disturbances, and the potentially strong impact of changing disturbance regimes on forest resources, investigating climatic drivers of destructive bark beetle outbreaks is of paramount importance. We analyzed 17 time-series of the amount of wood damaged by Ips typographus, the most destructive pest of Norway spruce forests, collected across 8 European countries in the last three decades. We aimed to quantify the relative importance of key climate drivers in explaining timber loss dynamics, also testing for possible synergistic effects. Local outbreaks shared the same drivers, including increasing summer rainfall deficit and warm temperatures. Large availability of storm-felled trees in the previous year was also strongly related to an increase in timber loss, likely by providing an alternative source of breeding material. We did not find any positive synergy among outbreak drivers. On the contrary, the occurrence of large storms reduced the positive effect of warming temperatures and rainfall deficit. The large surplus of breeding material likely boosted I. typographus population size above the density threshold required to colonize and kill healthy trees irrespective of other climate triggers. Importantly, we found strong negative density dependence in I. typographus that may provide a mechanism for population decline after population eruptions. Generality in the effects of complex climatic events across different geographical areas suggests that the large-scale drivers can be used as early warning indicators of increasing local outbreak probability.
Forfattere
Sigridur Dalmannsdottir Marit Jørgensen Marcin Rapacz Liv Østrem Arild Larsen Rolf Rødven Odd Arne RognliSammendrag
The effect of variable autumn temperatures in combination with decreasing irradiance and daylength on photosynthesis, growth cessation and freezing tolerance was investigated in northern- and southern-adapted populations of perennial ryegrass (Lolium perenne) and timothy (Phleum pratense) intended for use in regions at northern high latitudes. Plants were subjected to three different acclimation temperatures; 12, 6 and 9/3°C (day/night) for 4 weeks, followed by 1 week of cold acclimation at 2°C under natural light conditions. This experimental setup was repeated at three different periods during autumn with decreasing sums of irradiance and daylengths. Photoacclimation, leaf elongation and freezing tolerance were studied. The results showed that plants cold acclimated during the period with lowest irradiance and shortest day had lowest freezing tolerance, lowest photosynthetic activity, longest leaves and least biomass production. Higher acclimation temperature (12°C) resulted in lower freezing tolerance, lower photosynthetic activity, faster leaf elongation rate and higher biomass compared with the other temperatures. Photochemical mechanisms were predominant in photoacclimation. The northern-adapted populations had a better freezing tolerance than the southern-adapted except when grown during the late autumn period and at the highest temperature; then there were no differences between the populations. Our results indicate that the projected climate change in the north may reduce freezing tolerance in grasses as acclimation will take place at higher temperatures and shorter daylengths with lower irradiance.
Sammendrag
Farmers are exposed to climate change and uncertainty about how that change will develop. As farm incomes, in Norway and elsewhere, greatly depend on government subsidies, the risk of a policy change constitutes an additional uncertainty source. Hence, climate and policy uncertainty could substantially impact agricultural production and farm income. However, these sources of uncertainty have, so far, rarely been combined in food production analyses. The aim of this study was to determine the effects of a combination of policy and climate uncertainty on agricultural production, land use, and social welfare in Norway. Output yield distributions of spring wheat and timothy, a major forage grass, from simulations with the weatherdriven crop models, CSM-CERES-Wheat and, LINGRA, were processed in the a stochastic version Jordmod, a price-endogenous spatial economic sector model of the Norwegian agriculture. To account for potential effects of climate uncertainty within a given future greenhouse gas emission scenario on farm profitability, effects on conditions that represented the projected climate for 2050 under the emission scenario A1B from the 4th assessment report of the Intergovernmental Panel on Climate Change and four Global Climate Models (GCM) was investigated. The uncertainty about the level of payment rates at the time farmers make their management decisions was handled by varying the distribution of payment rates applied in the Jordmod model. These changes were based on the change in the overall level of agricultural support in the past. Three uncertainty scenarios were developed and tested: one with climate change uncertainty, another with payment rate uncertainty, and a third where both types of uncertainty were combined. The three scenarios were compared with results from a deterministic scenario where crop yields and payment rates were constant. Climate change resulted in on average 9% lower cereal production, unchanged grass production and more volatile crop yield as well as 4% higher farm incomes on average compared to the deterministic scenario. The scenario with a combination of climate change and policy uncertainty increased the mean farm income more than a scenario with only one source of uncertainty. On the other hand, land use and farm labour were negatively affected under these conditions compared to the deterministic case. Highlighting the potential influence of climate change and policy uncertainty on the performance of the farm sector our results underline the potential error in neglecting either of these two uncertainties in studies of agricultural production, land use and welfare.
Forfattere
Kris Verheyen Pieter De Frenne Lander Baeten Donald M. Waller Radim Hédl Michael P. Perring Haben Blondeel Jörg Brunet Markéta Chudomelová Guillaume Decocq Emiel De Lombaerde Leen Depauw Thomas Dirnböck Tomasz Durak Ove Eriksson Frank S. Gilliam Thilo Heinken Steffi Heinrichs Martin Hermy Bogdan Jaroszewicz Michael A. Jenkins Sarah E. Johnson Keith J. Kirby Martin Kopecký Dries Landuyt Jonathan Lenoir Daijiang Li Martin Macek Sybryn L. Maes František Máliš Fraser J.G. Mitchell Tobias Naaf George Peterken Petr Petřík Kamila Reczyńska David A Rogers Fride Høistad Schei Wolfgang Schmidt Tibor Standovár Krzysztof Świerkosz Karol Ujházy Hans Van Calster Mark Vellend Ondřej Vild Kerry Woods Monika Wulf Markus Bernhardt-RömermannSammendrag
More and more ecologists have started to resurvey communities sampled in earlier decades to determine long-term shifts in community composition and infer the likely drivers of the ecological changes observed. However, to assess the relative importance of and interactions among multiple drivers, joint analyses of resurvey data from many regions spanning large environmental gradients are needed. In this article, we illustrate how combining resurvey data from multiple regions can increase the likelihood of driver orthogonality within the design and show that repeatedly surveying across multiple regions provides higher representativeness and comprehensiveness, allowing us to answer more completely a broader range of questions. We provide general guidelines to aid the implementation of multiregion resurvey databases. In so doing, we aim to encourage resurvey database development across other community types and biomes to advance global environmental change research.
Forfattere
Johannes M. Baveco Anne Kari Bergjord Olsen Jarle W. Bjerke Magda E. Chudzinska Loïc Pellissier Caroline E. Simonsen Jesper Madsen Ingunn Tombre Bart A. NoletSammendrag
Many goose species feed on agricultural land, and with growing goose numbers, conflicts with agriculture are increasing. One possible solution is to designate refuge areas where farmers are paid to leave geese undisturbed. Here, we present a generic modelling tool that can be used to designate the best locations for refuges and to gauge the area needed to accommodate the geese. With a species distribution model, locations are ranked according to goose suitability. The size of the area to be designated as refuge can be chosen by including more or less suitable locations. A resource depletion model is then used to estimate whether enough resources are available within the designated refuge to accommodate all geese, taking into account the dynamics of food resources, including depletion by geese. We illustrate this with the management scheme for pink-footed goose Anser brachyrhynchus implemented in Norway. Here, all geese can be accommodated, but damage levels appear to depend on weather, land use and refuge size.
Sammendrag
There is a scientific consensus that the future climate change will affect grass and crop dry matter (DM) yields. Such yield changes may entail alterations to farm management practices to fulfill the feed requirements and reduce the farm greenhouse gas (GHG) emissions from dairy farms. While a large number of studies have focused on the impacts of projected climate change on a single farm output (e.g. GHG emissions or economic performance), several attempts have been made to combine bio-economic systems models with GHG accounting frameworks. In this study, we aimed to determine the physical impacts of future climate scenarios on grass and wheat DM yields, and demonstrate the effects such changes in future feed supply may have on farm GHG emissions and decision-making processes. For this purpose, we combined four models: BASGRA and CSM-CERESWheat models for simulating forage grass DM and wheat DM grain yields respectively; HolosNor for estimating the farm GHG emissions; and JORDMOD for calculating the impacts of changes in the climate and management on land use and farm economics. Four locations, with varying climate and soil conditions were included in the study: south-east Norway, south-west Norway, central Norway and northern Norway. Simulations were carried out for baseline (1961–1990) and future (2046–2065) climate conditions (projections based on two global climate models and the Special Report on Emissions Scenarios (SRES) A1B GHG emission scenario), and for production conditions with and without a milk quota. The GHG emissions intensities (kilogram carbon dioxide equivalent: kgCO2e emissions per kg fat and protein corrected milk: FPCM) varied between 0.8 kg and 1.23 kg CO2e (kg FPCM)−1 , with the lowest and highest emissions found in central Norway and south-east Norway, respectively. Emission intensities were generally lower under future compared to baseline conditions due mainly to higher future milk yields and to some extent to higher crop yields. The median seasonal aboveground timothy grass yield varied between 11,000 kg and 16,000 kg DM ha−1 and was higher in all projected future climate conditions than in the baseline. The spring wheat grain DM yields simulated for the same weather conditions within each climate projection varied between 2200 kg and 6800 kg DM ha−1 . Similarly, the farm profitability as expressed by total national land rents varied between 1900 million Norwegian krone (NOK) for median yields under baseline climate conditions up to 3900 million NOK for median yield under future projected climate conditions.
Forfattere
Hong Yang Junqiang Xia Roger J. FlowerSammendrag
Det er ikke registrert sammendrag
Forfattere
Lars G. F. Tellnes Christelle Ganne-Chedeville Ana Cláudia Dias Franz Dolezal Callum Aidan Stephen Hill Edwin Zea EscamillaSammendrag
The forest and building sector is of major importance in climate change mitigation and therefore construction materials based on forest products are of great interest. While energy efficiency has had a large focus in climate change mitigation in the building sector, the carbon footprint of the construction material is gaining relevance. The carbon footprint of construction materials can vary greatly from one type to another, the building sector is consequently demanding documentation of the carbon footprint of the materials used. Using an environmental product declaration (EPD) is an objective and standardised solution for communicating the environmental impacts of construction products and especially their carbon footprint. Nevertheless, it is challenging to include the features of forest products as pools of carbon dioxide. There is currently a focus on research into methods for the accounting of sequestered atmospheric carbon dioxide and also implementation of these methods into technical standards. This paper reviews the recent research and technical standards in this field to promote a common understanding and to propose requirements for additional information to be included in EPDs of forest-based products. The main findings show the need for reporting the contribution of biogenic carbon to the total on greenhouse gas emissions and removals over the product’s lifecycle. In order to facilitate the implementation of more advanced methods from research, the EPD should also include more detailed information of the wood used, in particular species and origin.
Forfattere
Patrick Rousset Bilel Mondher Kevin Candellier Ghislaine Volle Janka Dibdiakova Gilles HumbertSammendrag
Charcoal seems one of the most promising bio-reducer because of its high coke replacement ratio in blast furnaces. Nevertheless, biochar materials are subject self-combustion during storage, handling and transport, and need to be studied in order to understand and limit these phenomena. Heat-based methods: were employed to compare and determine the self-ignition parameters of four types of fresh biochar (Quercus pubescens, Cyclobalanopsis glauca, and Trigonostemon huangmosun, Bambusa vulgar) that are used as bioreducers in the silica industry. This study assumed that spontaneous combustion arises from exothermic oxygen chemisorption to fresh biochar surface. Sample mass, heat flow and CO2 desorption were measured. The weight increased very rapidly as soon as the gas stream was changed from N2 to air accompanying the heat generation for each material. Desorption isotherms were found to depend on the nature of the feedstock confirming that bamboo biochar was the most reactive one under air exposure.
Sammendrag
Det er ikke registrert sammendrag