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.
2003
Sammendrag
At present there are nearly 20 000 milk producers in Norway, and approximately 10 per cent of them are members of the Norwegian Dairy Financial Recording (NDFR). The NDFR is an important basis for production and financial advice given by the dairies. There is a great interest among milk producers and advisors in comparing results from different farms to find out why some are doing well and some are doing not so well, and to learn from those doing well. Gross margin (GM) per litre of milk produced is the traditional indicator for efficiency. This data, as other data on milk production, indicate that there is a wide variation in gross margin per litre of milk between farms with seemingly similar conditions for producing milk. This is interpreted as a potential for improving the efficiency of many producers. However, for many reasons gross margin per litre of milk is not an ideal indicator. A new version of the NDFR contains more information, for instance information on fixed costs of roughages produced on the farm. It is hoped that the new version of the NDFR makes it a better tool for improving the profitability of milk production. In an ongoing project we try to use the NDFR to analyse who are doing well and why. We use a combination of Data Envelopment Analysis (DEA) and statistical analysis. For each farm we produce an efficiency index, and then we apply statistical methods to find factors that can explain the index. So far we have only very preliminary results. Management factors are important, but the NDFR data-base have very little information on management factors. It is planned to collect such data for a sample of farmers and include that in the study at a later stage.
Forfattere
Grete StokstadSammendrag
Several factors influence the value of a lamb carcass throughout the slaughtering season, and therefore have implications for the optimal slaughtering time of lambs. The expected price of the carcass varies through the season due to: Variations in the weight of the lambs, and the growth through the season. The classification of the carcass, i.e., the price per kg changes as the lambs grow. The prices of the various quality changes throughout the season. The quality of the grazing fields limits the possible weight gain and influences the classification of lams. The grazing resources are in general limited, and will affect the possibility of fattening lambs in the fall. The objective with this study is to come up with a tool to help in determining when to slaughter which lambs in the fall when resources are limited. In order to make good decisions, the first step is to calculate the profitability of various slaughtering decisions. I use known characteristics of the lambs as weight, sex etc. to determine expected value of the carcass if slaughtered at various point in time in the future. In order to determine expected quality for the carcasses I have used a multinomial ordered probit regression model to determine the probability for obtaining a particular classification. A linear programming model is used to choose the best alternatives given limited grassing resources. The model can be used to determine optimal slaughtering decisions given a particular group of lambs and resources. By limiting the possible choices in the model, the model user may also investigate the losses associated with alternative slaughtering schemes. In this paper I describe the forecasting models for determining the value of the carcass, I describe the general linear programming model and show some results from running the model.
Sammendrag
The Norwegian Ministry of Agriculture (1999) has announced its goal of converting 10% of the total agricultural area to organic farming methods by the year 2009. Considerations of profitability and risk will be especially important, when the conversion of a farm is planned. Studies of risk and risk management in organic farming have been lacking in Norway. Only very few such studies have been carried out internationally, thus showing that there is a definite need for more risk and risk management research in organic farming. The project aims to increase knowledge about risks and risk management in organic farming systems. It is a co-operation between NILF, NORSK, and NVH. Both biological and economic aspects of risk will be taken into consideration. We wish to test and apply acknowledged statistical and risk analysis theories and methods on issues related to organic farming. The project will deal with the extent of risk in organic farming, strategies used by organic farmers to handle risk and whole-farm models to analyse optimal economic solutions under uncertainty in organic farming. The project will cover farms that are still in conversion and completely converted farms. Results from the project will directly benefit farmers and farm advisers. Politicians and public administrators will receive access to significant information for the design of future policies.
Forfattere
Mauritz Åssveen Håkon Linnerud Frank Enger Jan Bjørn KvammeSammendrag
Bygg- og havresorter er prøvd i forsøk på Sør-Vestlandet. Både siste sesongs resultater og sammendrag over år presenteres.
Forfattere
Arve ArsteinSammendrag
Tørt og kaldt verlag i november og desember i fjor etterfylgt av mildversperiodar og regn i januar gav eit uvanleg tjukt isdekke på enga i store delar av Sogn og Fjordane. Isen fekk tidleg stor merksemd sidan ein kattapiss-liknande eim la seg i dalbotnane og var til ubehag for folk flest. Dette skuldast oppblomstring av bakteriar under isen på solrike dagar.
Sammendrag
Arbeidet viser at dekking med plasttak i søtkirsebær reduserer angrep av rotesoppar og kan erstatta bruk av soppmiddel. Di lengre periode fruktene er dekka med tak, di mindre trong er det for soppmiddel. Dekking heilt frå blomstring uten sprøyting gav like godt resultat som dekking 3 til 4 veker før hausting og 2 til 5 sprøytingar.
Sammendrag
Årleg gjødsling med minimum 10 kg kalium pr dekar er naudsynt for å oppretthalde avlingsnivået i økologisk dyrka eng på kaliumfattig jord. Kaliummangel i timotei er først synleg når konsentrasjonen av kalium kjem under 1,5%. Husdyrgjødselmengdene på eit økologisk drive gardsbruk er moderate. Tilførselen av kalium vert dermed liten, og innhaldet av både timotei og kløver vert redusert. 5 kg kalium pr dekar i tillegg til 3 tonn gylle vil betre situasjonen mykje.
Forfattere
Trond Knapp Haraldsen Per Anker PedersenSammendrag
Det er ikke registrert sammendrag
Forfattere
Tor J. JohansenSammendrag
Det er ikke registrert sammendrag
Forfattere
Bjørn Åge Tømmerås Trond Hofsvang Anders Jelmert Odd Terje Sandlund Helge Sjursen Leif SundheimSammendrag
Rapporten omhandler marine organismer, internasjonal handel og skadeorganismer, pattedyr og fugl og karplanter