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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.

2003

Abstract

Wintering ability in the field and resistance to different winter-stress factors under controlled environmental conditions were studied in a full-sib family of perennial ryegrass (Lolium perenne L.). Significant variation in tolerance to freezing and ice encasement, resistance to pink snow mould (Microdochium nivale) and also in winter survival and spring growth were found between the different genotypes. No strong correlations were found between the resistances to the different stress factors. These results indicate that resistance to different winter-stress factors is controlled by separate genes in perennial ryegrass. A low but significant positive correlation was found between spring growth of plants in the field after the first winter and both freezing tolerance and M. nivale resistance measured in controlled environments. Cold hardening seemed to influence freezing tolerance and M. nivale resistance differently in the different genotypes, since no distinct correlation in tolerance to freezing or resistance to M. nivale was found between unhardened and hardened plants. Tolerance or resistance to most of the winter stress factors measured was positively correlated with plant size.

Abstract

Modern information technology allows the investigation of the characteristic properties of living systems from a new perspective. Which of the ecosystem features are necessary conditions resulting from their constraints, which are accidental, constituting contingent facts of their respective histories?As long as we know of a single phylogenetic tree in nature, the difference is hard to tell, rendering the reconstruction and realisation of artificial ecologies a major challenge. It has been taken up by the high technology of the time since decades; since two decades, IT is leading in this respect.Are there life forms that can be created in contemporary computers, and which ones? Successes and failures of a number of virtualizations are forming de facto constraints for theoretical ecosystem research. Artificial Life (AL) research appears to be not just another attempt towards realistic models for ecological systems, but undermines the basic assumptions of most of conventional modeling in this area: in AL, behavior is in general irreducible to internal mechanisms; behavior results rather from interactive and intentional usage of the simulation.We try to elucidate and demonstrate the crucial role of interaction in these simulations, drawing from current developments in theoretical computer science as well as a number of examples. We propose a new classification of ecosystem models according to its degree of interactivity.

Abstract

The report is investigating the current state of forestry, forest industries and the bioenergy sector in Denmark, Estonia, Finland, Latvia, Lithuania, Norway and Sweden. The main task of the research is to illustrate the current supply and use of wood based fuels in the Baltic and Nordic countries. Additionally the present use of forest fuels in the different countries in the private and industrial sector is analyzed and bottlenecks in the current supply of forest fuels are identified. The focus on energy policy has been on energy systems with less CO2 emissions in order to meet requirement of international agreements. Therefore, forest fuels offer great potential as a source of renewable energy. There has been a steady increase in the growing stock of European forests. Large amounts of residues are left unutilised both in Nordic and Baltic forests, especially in first thinnings and intermediate cuttings. They offer large potential to further increase the share of wood fuels in total energy consumption. Forest industries utilize a great share of wood residues at present but especially in Baltic regions there is potential to intensify the use of wood residues. An additional increase in wood biomass utilization is also dependent on future expansion of the district heating networks in Nordic and Baltic countries. Potential is available especially in the Baltic countries and Norway. The situation in regards to utilization of wood biomass in private dwellings is similar in all seven countries. Large amounts of fuelwood are consumed annually but new furnace and burner technology is necessary to use resources more efficiently. In regards to energy policy a lot has been done to improve the use of biomass utilization, but more has to be done to strengthen the position of forest fuels in the future. The main bottlenecks for the larger use of forest biomass were found to be a lack of utilisation of available technology for harvesting and transport operations and a lack of district heating. An improved use of technology would decrease the price of forest fuels, necessary to compete with fossil fuel prices on international markets.

2002

Abstract

Development of environmentally and economically sound agricultural production systems is an important aim in agricultural policy and has a high priority in agricultural research worldwide. The present work uses results from the first complete crop rotation period (1990-1997) of the Apelsvoll cropping system experiment in south-eastern Norway, to discuss the effect of cropping systems and their management practices on environment, soil fertility, crop yields and the farm economy, and how this knowledge may be used to develop a more sustainable agriculture. The experiment includes conventional arable (CON-A), integrated arable (INT-A), ecological arable (ECO-A), conventional forage (CON-F), integrated forage (INT-F) and ecological forage (ECO-F) cropping systems which were established on model farms of 0.2 ha. On the basis of nutrient runoff, soil erosion and pesticide contamination, the following ranking from the most to the least favourable was made for environmental effects: INT-F> ECO-F> ECO-A> INT-A> CON-F> CON-A. Environmental effects such as N and P runoff losses were very much linked to the proportion of ley in the system. Thus, major improvements to reduce the effects of agriculture on nutrient runoff, cannot be achieved without changing the cropping systems in the direction of more mixed farming with reduced cropping intensity. The nutrient balance calculations showed that there were considerable deficits in the ecological systems, a fact which must be taken into consideration in the development of sustainable ecological cropping systems. The yield reduction experienced with integrated and ecological cropping, relative to conventional cropping, was smaller for forage crops and potatoes than for cereals. This suggests that it is easier to maintain the yield level by reduced cropping intensity in mixed farming systems with livestock than in arable farming systems without livestock. Because of the premium prices and government subsidies to ecological farming, the economic results were equally good in the ecological systems as in the conventional ones. Economically, integrated farming was less favourable than the other systems. It is concluded that, overall, integrated and ecological forage systems results in the least environmental harm, and based upon the present government subsidies, the forage systems also seem the most profitable, along with the ecological arable system.

To document

Abstract

The article evaluates the usefulness and shortcomings of agency theory as a framework for discussing the future of Norwegian agricultural cooperatives. The first argument is that agency theory ignores the significance of the traditional collective thinking in Norwegian agricultural cooperatives. In this respect, agency theory is incomplete and its explanatory power is low. The second point is that, nevertheless, the value of applying agency theory as a conceptual tool may increase in the close future, due to the emerging of novel industrial strategies and new cooperative forms. Some of the crucial agencyproblems may come to the forefront, and increasingly imprint the agenda of Norwegian agricultural cooperatives.