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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.

1999

Sammendrag

The impact of elevated CO2 on height increment, phenology, biomass, and concentration of carbohydrates, pigments and elements in clones of Norway spruce (Picea abies (L.) Karst ) were studied in a three year open-top chamber experiment. The CO2-effect on height increment, biomass, and concentration elements of Silver birch (Betula pendula Roth.) was also recorded. The CO2 concentrations were ambient (380 µmol mol-1), approximately 500 and 700 µmol mol-1 CO2 in the chambers. Additionally, an outside control plot was present. Norway spruce were grown in intact profiles of forest soil and in fertilised peat. Silver birch was grown in forest soil only. Phenology and leader shoot extension were recorded regularly. Element concentrations of leaves and needles were analysed at the end of each growth season. At the end of the experiment, carbohydrate and pigment concentrations were also analysed. The impact of elevated CO2 on Silver birch and Norway spruce was small in this experiment. A marginal increase in biomass were recorded in Silver birch and in Norway spruce grown in fertilised peat. Phenology, concentration of elements, C:N ratio, concentrations of carbohydrates and pigments were almost unaffected by elevated CO2. The largest effect on growth and chemical composition were caused by chambers versus outside control plots and difference in nutrient supply (Norway spruce). Significant higher concentration of Al, Na and Fe were recorded in both species in the outside control plots compare to the plants inside the chambers. The increased concentration of these elements could be caused by a higher dust exposure outside the chambers than inside

Til dokument

Sammendrag

The World Trade Organization (WTO) will initiate negotiations on the further liberalization of the global trade with agricultural commodities by the end of 1999. These negotiations are basedon Article 20 of the Uruguay Round’s Agreement on Agriculture, which states, inter alia, that the reform process is to be continued, with the long-term objective of substantial and progressive reductions in the support and protection of the agricultural sector. In this context, however, a number of issues are to be taken into consideration, including the so-called non-trade concerns. The Norwegian authorities have started preparations for the new round of WTO negotiations, and have placed substantial emphasis on the non-trade concerns. Norwegian agriculture is regarded as being a ”producer” of more than just food and fibres, for example, national food security, viable rural areas and environmental benefits. The term ”Multifunctional Agriculture” is being increasingly applied to describe these additional functions1. With regard to Norwegian agriculture, it will be of major importance for Norway that sufficient consideration is given to the non-trade and other concerns during the next round of the WTO negotiations. In the summer/fall of 1998, the Norwegian Ministry of Agriculture initialized an evaluation program in order to survey and analyse a number of issues in relation to ”multifunctional agriculture”. The present report is one of the contributions in this context.

Sammendrag

This report was written in connection with the preparations of the Norwegian authorities for the new round of WTO negotiations on further liberalization of world trade. The report surveys the natural conditions in Australia, France, New Zealand, Norway and the USA, and studies their influence on agriculture, e.g., on farm size, farmland distribution, types of production and production costs. However, it is not easy to limit the analysis to merely the natural conditions for farming, since a number of other political, legal, economic, historic and cultural factors also determine the conditions for agriculture in a country. The report includes agroclimatic data such as length of growing-season, temperature sums, mean temperatures and mean precipitation. Not surprisingly, the climate in Australia and New Zealand is significantly different from the climate in Norway. In these two countries, low temperatures are not a major growth-limiting factor, as they are in (parts of) France, Norway and the USA. Especially in Australia, growth is mainly limited by too high temperatures, excessive radiation, evaporation and lack of rainfall. [...]

Sammendrag

In this paper we first discuss the consumption behaviour of Norwegian farm households. Then, possible consumption models are outlined and our data sample is described. In the next section we discuss the use of panel data methods to estimate our consumption function. Finally, the results from estimating a consumption function with the DPD computer program are discussed. The preliminary results indicate that the GMM estimation using the system estimator of Blundell and Bond (1998) may be superior to the other methods. The parameter of the lagged dependent variable is inside the limits indicated by the OLS and the within estimator. The second lag of the dependent variable is rejected as an instrument and there are strong indications of serial correlation. Later on, we have to transform the model to make the serial correlation disappear. In a later version of this paper we will test if the MPC is changing over time. We will also test if there are different effects from price- and production dependent agricultural income and other income.

Sammendrag

The report is written by a working group of COST ACTION 711 `The operational applications of meteorology to agriculture, including horticulture". The report contains an overview and also a description of the most important data models of phenology and crop growth of wheat, barley and potato, and it contains a list of pest and disease models connected to the crops mentioned. Systems for gathering meteorological data and biological data to run the different models are discussed rather thoroughly, and the limitations of the existing models are also mentioned in this report.