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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.

2011

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The species composition of wood-inhabiting fungi (polypores and corticoids) was investigated on 1138 spruce logs and 992 pine logs in 90 managed and 34 natural or near-natural spruce and pine forests in SE Norway. Altogether, the study included 290 species of wood-inhabiting fungi. Comparisons of logs with similar properties (standardized tree species, decay class, dimension class) in natural and managed forests showed a significant reduction in species number per log in managed spruce forests, but not in managed pine forests. The species number per log in managed spruce forests was 10–55% lower than on logs from natural spruce forests. The reduction was strongest on logs of large dimensions. A comparison of 200–400 spruce logs from natural and managed forests showed a 25% reduction in species richness corresponding to a conservative loss of ca. 40 species on a regional scale. A closer inspection revealed that species confined to medium and very decayed spruce logs were disfavored in managed forests, whereas species on early decay classes and decay generalists were unaffected. Similarly, species preferring large spruce logs were disfavored in managed forests. Forest management had strongest impact on low-frequent species in the spruce forests (more than 50% reduction), whereas common species were modestly affected. Corticoid fungi were more adversely affected than polypore fungi. These results indicate that wood-decaying fungi in pine forests are more adapted to forest disturbances than spruce-associated species. Management measures securing a continuous supply of dead wood are more important in spruce forests than in pine forests.

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On small dairy farms, high investment costs and lack of investment capital may delay the modernising of facilities. The aim of this study was to investigate the importance of economics of scale in building costs of barns compared to other sources of variation in costs. The study includes 44 farms with a mean herd size of 49.5 ± 15.1 cows, built between year 1999 and 2006 and with a mean total area in the barns of 896 ± 454 m2. Building cost data were obtained from farmers and merged with construction, mechanisation and layout data from the same barns. Construction costs decreased up to approximately 1250 m2 while mechanisation costs and total building costs decreased up to approximately 1000 m2. A further increase in building area had only limited effect on the building costs per m2. Models including explanatory variables showed that milking and service area was significantly more expensive than other areas. AMS-barns were all together not significantly more expensive than other barns, since the increased mechanisation cost is offset by a lower requirement for milking area. Farmers remodelling their barns were able to realise a modernised building for a certain herd size for a lower cost compared to a completely new building. The use of their own effort varied considerably between projects. In many cases, farmers would be able to find alternative income sources with a higher hourly rate than the value of their own effort suggested by the model.

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The recent flooding episode in Norway from May this year shows the necessity of understanding the processes of water discharge from small tributaries feeding the larger river systems. The major objective of the recently started ExFlood project is to define and analyze measures to combat negative impact of extreme weather events on infrastructure in small watershed areas in Norway and to incorporate this in a land use planning tool. Urban, agriculture, nature, and forest areas and infrastructure elements demands different approaches concerning impacts of and opportunities for extreme weather events. The approach of the ExFlood project is to reduce the peak flow and delay the peak time to avoid damages on infrastructure. Three municipalities from different climate regions in Norway contribute to the project where the planning tool will be tested, and an experimental catchment site is selected to conduct in depth process studies.

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This paper analyzes the capabilities of three different governance regimes for adequately handling uncertain and unknown effects of genetically modified (GM) crops. Adequate handling requires the development of sound procedures for identification of uncertainty and ignorance (U&I), reduction of U&I, decisions on how to treat irreducible U&I and monitoring of unexpected effects. The nature of U&I implies, however, that these procedures will be highly incomplete. Governance mechanisms that facilitate cooperative adaptation and communicative rationality are therefore needed. The three governance regimes (GRs) compared are: GM-crops are produced by private firms and these firms are made liable for harm (GR1); GM-crops are produced by private firms and the government decides whether the crops should be marketed (GR2); and GM-crops are produced and the government decides whether the crops should be marketed (GR3). The effect of bringing the civil society into the decision-making process is also analyzed. GR3 will be stronger in cooperative adaptation and communicative rationality than GR2. Public research organizations have fewer conflicts of interest with the government than private firms, and academic norms are important. Difficulties in proving harm and identifying the responsible firm will make GR1 weak in cooperative adaptation and communicative rationality.

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The northernmost range of beech (Fagus sylvatica L.) is in southern Norway and consists of two distinct and isolated distributions, a single population at Seim in West Norway and several adjacent populations in Vestfold, East Norway. The modest beech pollen deposits beyond these main distributions suggest that the Norwegian beech distribution has never been an extension of the south Scandinavian range. We used genetic markers and historical sources to trace the ancestor populations for the beech at Seim and Vestfold, hypothesising Denmark as the most likely source. Nuclear inter-simple sequence repeat markers, amplified by polymerase chain reaction (PCR), were applied to estimate genetic distances between beech populations in Norway, England and Denmark. The variation in chloroplast DNA polymorphism was estimated using PCR-restriction fragment length polymorphism. The nuclear genetic data indicate Denmark as a source for the beech in Norway, although the data are less certain in the case of Seim than in that of Vestfold. The populations from South England were genetically different from most Scandinavian populations. The genetic variation within Norwegian populations was only slightly lower than that of the English and Danish populations, questioning birds as vectors for dispersal. Thus, the pollen data and our results are in accordance with the intentional introduction and documented human migrations across Skagerrak before and during the Viking Age.

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In this review, we provide an overview of the role of glucosinolates and other phytochemical compounds present in the Brassicaceae in relation to plant protection and human health. Current knowledge of the factors that influence phytochemical content and profile in the Brassicaceae is also summarized and multi-factorial approaches are briefly discussed. Variation in agronomic conditions (plant species, cultivar, developmental stage, plant organ, plant competition, fertilization, pH), season, climatic factors, water availability, light (intensity, quality, duration) and CO2 are known to significantly affect content and profile of phytochemicals. Phytochemicals such as the glucosinolates and leaf surface waxes play an important role in interactions with pests and pathogens. Factors that affect production of phytochemicals are important when designing plant protection strategies that exploit these compounds to minimize crop damage caused by plant pests and pathogens. Brassicaceous plants are consumed increasingly for possible health benefits, for example, glucosinolate-derived effects on degenerative diseases such as cancer, cardiovascular and neurodegenerative diseases. Thus, factors influencing phytochemical content and profile in the production of brassicaceous plants are worth considering both for plant and human health. Even though it is known that factors that influence phytochemical content and profile may interact, studies of plant compounds were, until recently, restricted by methods allowing only a reductionistic approach. It is now possible to design multi-factorial experiments that simulate their combined effects. This will provide important information to ecologists, plant breeders and agronomists.