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.
2004
Abstract
This study was conducted to explore organic and conventional dairy farmers perceptions of risk and risk management, and to examine relationships between farm and farmer characteristics, risk perceptions, and strategies. The data originate from a survey of conventional (n = 363) and organic (n = 162) dairy farmers in Norway. Organic farmers had the least risk averse perceptions. Institutional and production risks were perceived as primary sources of risk, with farm support payments at the top. Compared to their conventional colleagues, organic farmers gave more weight to institutional factors related to their production systems. Conventional farmers were more concerned about costs of purchased inputs and animal welfare policy. Organic and conventional farmers management responses were more similar than their risk perceptions. Financial measures such as liquidity and costs of production, disease prevention, and insurance were perceived as important ways to handle risk. Even though perceptions were highly farmer-specific, a number of socio-economic variables were found to be related to risk and risk management. The primary role of institutional risks implies that policy makers should be cautious about changing policy capriciously and they should consider the scope for strategic policy initiatives that give farmers some greater confidence about the longer term. Further, researchers should pay more attention to institutional risks.
Authors
Geir ØstrengAbstract
Artikkelen er basert på resultater fra et nordisk kurs i kalibrering av apparater for måling av CO2-frigivelse fra jord. Geir Østreng deltok på kurset med det apparatet som er brukt bl.a. i SIP Karbondynamikk i skogsjord 2000-2005, og han er medforfatter.
Abstract
No abstract has been registered
Abstract
Conventional extreme value statistics and the calculation of return periods implicitly assume stationarity of distributions and statistical independence at least asymptotically (most extreme events).We demonstrate, using a collection of river runoff time series from Southern Germany, that these assumptions are invalid, and that temporal as well as spatial correlations prevail instead: temporal differences of distributions are nearly synchronized within a region, and there are systematic trends of percentiles especially at low flow conditions within the 20th century.As a consequence, the estimated return periods of a given threshold flow are fluctuating, in some cases even in a dramatic fashion. On the other hand, a general trend towards an increase in flood frequencies cannot be stated on basis of our investigations, in accordance with other recent findings (Mudelsee et al. 2003), but contrary to general expectations drawn from climate change studies.
Authors
Ingrid OlesenAbstract
In spring 2003, the Nordic Gene Bank Farm Animals (NGH) proposed a follow up of the “Strategy for the conservation of genetic resources in the Nordic countries 2001-2004”. It was proposed to formulate criteria for sustainable animal breeding and guidelines for breeding organizations. Thus, the Norwegian Gene Resource Council decided to initiate the development of criteria for sustainable animal breeding and guidelines for breeding organizations in Norway.
Authors
Audun Øvrum Terje BirkelandAbstract
No abstract has been registered
Authors
Nina Elisabeth Nagy Lars Sandved Dalen D. L. Jones B. Swensen Carl Gunnar Fossdal Toril EldhusetAbstract
No abstract has been registered
Abstract
Artikkelen drøfter saltinnhold i ulike bygningsdeler i Bryggen i Bergen, saltets opphav og betydning i forhold til bevaring av trevirket. Ulike nedbrytningsorganismer i saltholdig tømmer er også vurdert.
Authors
K.M.J. Taulavuori E.B. Taulavuori Oddvar Skre Jan-Erik Ørnelund Nilsen B. Igeland Kari M. LaineAbstract
The aim was to elucidate the effects of elevated winter temperatures on the dehardening process of mountain birch (Betula pubescens ssp. czerepanovii) ecotypes and to evaluate their susceptibility to frost damage under warming climate conditions. Ecotypes from 60 to 71N latitudes and 20750 m altitudes were grown in northern Norway (70N) and subjected to simulation of the photoperiod in southern Norway (60N) by artificial illumination from September onwards. In November, the seedlings were transported to the south (60N) to overwinter at ambient or 4C above ambient temperatures. Frost hardiness and lipid peroxidation were determined during JanuaryApril. The higher winter temperature accelerated dehardening, and there were significant differences between the ecotypes. Among tree individuals of southern origin, the alpine ecotype exhibited the most rapid rate of dehardening, whereas the oceanic type showed the slowest rate. Lipid peroxidation supported the above findings. Since temperature elevation was unequal for the ecotypes with respect to climatic change, the frost hardiness results were normalized to obtain an equal 4C temperature rise. The risk of frost injury seemed to be lowest in the northernmost ecotypes under a temperature elevation of 4C, obviously due to their adaptation to a wider temperature range.
Abstract
A method for determination of the climate gases CH4, CO2 and N2O in air samples and soil atmosphere was developed using GC-MS. The method uses straightforward gas chromatography (separation of the gases) with a mass spectrometric detector in single ion mode (specific determination).The gases were determined with high sensitivity and high sample throughput (18 samples h1). The LOD (3) for the gases were 0.10 L L1 for CH4, 20 L L1 for CO2 and 0.02 L L1 for N2O. The linear range (R2 = 0.999) was up to 500 L L1 for CH4, 4000 L L1 for CO2 and 80 L L1 for N2O. The samples were collected in 10 mL vials and a 5 L aliquot was injected on column.The method was tested against certified gas references, the analytical data gave an accuracy within 5% and a precision of 3%. The presence of 10% by volume of C2H2 (often used experimentally to prevent N2 formation from N2O) did not interfere with detection for the targeted trace gases.