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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.

2011

Abstract

This ESEE 2011 conference paper examines attitudes to private and public goods and bads from agriculture in Norway with a particular focus on organic agriculture. The issue is based on a survey among 939 Norwegians. The results show that the respondents strongly value public attributes of agriculture like a vivid countryside and cultural landscapes. Almost 60 percent of the sample emphasise that the government should aim to increase the production and sale of organic food. Respondents’ behaviour as consumers were investigated by collecting and analysing data that indicate which conditions respondents find most important when they buy milk, eggs, carrots and ketchup. Important conditions were taste, fresh, produced in Norway and no use of pesticides or fertilizers. The most important reasons for buying organic food were avoidance of pesticides, health and environmental concerns.

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Abstract

Along the succession gradient of the boreal forest ecosystem, black grouse Tetrao tetrix inhabits the early and capercaillie Tetrao urogallus the latest stages. When converting old forest to clearcuts and plantations, commercial forestry has therefore been assumed to affect capercaillie negatively and to be favourable to black grouse. During a 30-year period (1979–2008) we monitored sympatric populations of the two species in a forest in southeast Norway based on annual spring and autumn censuses and radio-marked birds. During this period, the proportion of old, semi-natural forest was halved and clearcuts and young plantations increased accordingly. The grouse populations did not change as predicted. While the trend in August numbers of adult black grouse declined, males more than females, abundance of adult capercaillie remained unchanged. Number of males at leks showed similar patterns. Equally surprising, breeding success (number of chicks per female in August) of both species increased, thus indicating that the populations were regulated more by variation in adult survivorship than by recruitment of young birds. No correlations were found with changing climatic factors (precipitation and temperatures in winter and spring, snow depth and time of snow melt), except that year-to-year breeding success was positively correlated with minimum temperatures during 2 weeks posthatch. The results are explained by a combination of more flexible habitat selection than previously assumed and a changing predator regime: In the early period, nearly all capercaillie leks were located in old, semi-natural forest, but as plantations grew older (>30 years), new leks were established there. Similarly, while young capercaillie broods used old semi-natural forest almost exclusively when the study started, they frequently used middle-aged plantations, especially those with a ground cover of bilberry Vaccinium myrtillus, when these became common in later years. The increasing breeding success could largely be explained by more females rearing chicks successfully, presumably due to a marked decline in the main nest predator, the red fox Vulpes vulpes. A practice of thinning of the old, semi-natural forest some years prior to final harvesting probably facilitated predation of black grouse by goshawks Accipiter gentilis. Contrary to many beliefs, our results indicate that both capercaillie and black grouse are quite tolerant to changes in forest management regimes. In our study, numerical and functional responses of predators (mainly red fox and goshawk) apparently played a more important role in regulating grouse numbers than habitat factors per se.

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Abstract

Grouse and vole numbers may peak after peaks in the seed crop of bilberry (Vaccinium myrtillus) because of reduced levels of feeding deterrents in bilberry plants. We predicted that grouse reproduction depends also on summer (June-September) temperatures in the 2 previous years, because bilberry plants will be less exhausted after a high seed crop in or after warm summers, and thus rebuild their chemical defence more quickly. After berry peak years, population indices of capercaillie (Tetrao urogallus) and bank vole (Myodes glareolus) in southern Norway were negatively related to summer temperatures in the previous year or previous 2 years. Willow grouse (Lagopus lagopus) chick production in five areas in Norway was negatively related to summer temperatures in the 2 previous years when controlling for vole density. A similar pattern was found for the bilberry-feeding moth (Eulithis populata), an important prey for grouse chicks. In eastern Norway, autumn densities of capercaillie and black grouse (Tetrao tetrix) were more likely to peak in vole peak years at high altitudes, where summer temperatures are low. We conclude that high summer temperatures may limit grouse reproduction through the effect on bilberry plants and that a warm climate thus adversely affects population levels of grouse.

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Abstract

As a primary industry, agriculture is directly dependent on natural conditions and therefore potentially vulnerable to the consequences of climate change. In Norway and Northern Norway in particular, the future climatic changes are expected to be overall positive. Still, the consequences for agriculture are not straightforward, but dependent on the interaction between different weather and biological elements, as well as political, economic and social conditions. In this interdisciplinary study we have assessed biological and agronomic effects of climate change, and their interaction with political, economic and social factors, to identify farmers' vulnerability and adaptive capacity to climate change. The assessments are based on downscaled climate change scenarios and interviews with local farmers in the three northernmost counties in Northern Norway (latitude 65.5° to 70°). The study shows that the farmers to a degree are vulnerable to a changing climate, not mainly because of the direct effects of changing growing conditions, but because these changes are an added factor to an already tenuous situation created by Norwegian agricultural policy and socio-economic development in general. We have found that farmers are highly adaptive, to both changing growing conditions and changing agricultural policies. However, changes in policy are currently a greater challenge to farmers than climate change, and such changes are therefore a more salient driver of vulnerability.