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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.

2021

Abstract

Field-based monitoring of deer food availability and browsing on recruiting forest trees is a necessary but labour-intensive task. We explored how such estimates from a low-resolution multipurpose national forest inventory (NFI) (plot density 0.3 km−2) corresponded with estimates from local inventories that specifically and in greater detail monitor the availability of deer food and browsing intensity (LFI) (plot density 2–3 km−2). We used NFI and LFI data from 16 moose Alces alces ranges (mean area 276 ± SE 69 km2) in southern Norway. Only the height segment 30–130 cm of browsable trees could be obtained from the NFI data, while moose can browse trees from 30 to 300 cm in height. According to the LFI, the browse species did not have similar proportions of their browsable stems below 130 cm. Using only the stems from heights of 30–130 cm overestimated the availability of RAS (rowan, aspen and sallow) relative to birch (silver birch and downy birch) and Scots pine. The browsable biomass per stem of each species also varied between ranges, which introduces uncertainty to the food availability estimates that are based on stems only. Nevertheless, the NFI density of stems at 30–130 cm heights can be a useful index for species-specific comparisons of browse availability across ranges, because the variations between ranges in stem densities outweighed the biomass variations per stem. The NFI and LFI estimates of the species-specific densities of stems at 30–130 cm heights were significantly related and close to isometric (1:1), especially for RAS and pine. We did not find strong relationships between NFI and LFI in the browsing intensity (i.e. proportion of shoots that were browsed during the winter). The explained variation was only 11% (R2) for RAS (p = 0.281) and 32% for pine (p = 0.028). This was likely due to the small sample sizes of browsed trees in the NFI and methodological differences between the NFI and LFI in how browsing intensity is estimated. Conclusions Using data from national forest inventories can be an efficient but low-resolution way to monitor browse availability for deer, provided that the monitoring includes the full range of tree heights reachable for the deer (e.g., 30–300 cm for moose). It is also a prerequisite that the number of NFI plots is sufficient to cover the spatial variability of the area. Regarding browsing intensities, adjustments in both the NFI and LFI approaches are needed to make the two monitoring schemes more comparable.

Abstract

There is an increasing use of carcass detection dogs to find remains of dead livestock in Norwegian rangelands. But how effective are these dogs actually? • We compared the efficiency of approved carcass detection dog equipages (CDEs, i.e., dog and man) with people searching for sheep carcasses without dogs. • CDEs found significantly more carcasses than people without dogs, and kilometers traveled and minutes spent per carcass detection indicated that dogs were >3x as effective in their search. However, CDEs found only 1 in 4 of the carcasses laid out experimentally. • The training program for CDEs in Norway is now adjusted to improve the quality of the equipages. • The effort of sheep CDEs is important to Norwegian sheep farmers applying for compensation because of the increase in percentage of proven losses caused by protected carnivores. • In the future carcass detection dogs in Norway could be used for wildlife conservation and management tasks.

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Abstract

Aims Understanding fine-grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine-grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the former three groups). Location Palaearctic biogeographic realm. Methods We used 126,524 plots of eight standard grain sizes from the GrassPlot database: 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 and 1,000 m2 and calculated the mean richness and standard deviations, as well as maximum, minimum, median, and first and third quartiles for each combination of grain size, taxonomic group, biome, region, vegetation type and phytosociological class. Results Patterns of plant diversity in vegetation types and biomes differ across grain sizes and taxonomic groups. Overall, secondary (mostly semi-natural) grasslands and natural grasslands are the richest vegetation type. The open-access file ”GrassPlot Diversity Benchmarks” and the web tool “GrassPlot Diversity Explorer” are now available online (https://edgg.org/databases/GrasslandDiversityExplorer) and provide more insights into species richness patterns in the Palaearctic open habitats. Conclusions The GrassPlot Diversity Benchmarks provide high-quality data on species richness in open habitat types across the Palaearctic. These benchmark data can be used in vegetation ecology, macroecology, biodiversity conservation and data quality checking. While the amount of data in the underlying GrassPlot database and their spatial coverage are smaller than in other extensive vegetation-plot databases, species recordings in GrassPlot are on average more complete, making it a valuable complementary data source in macroecology.

2020

Abstract

When free-ranging animals encounter traffic on roads or railways, it may have fatal outcome. In Europe, collisions between vehicles and animals have increased the last 40 years, causing eco-nomic losses and serious welfare concerns. Today there is no technological solution to prevent such collisions in the rough, arctic climate that represents most parts of Norway. By using small and energy-efficient radio transmitters moulded into headcollars, researchers have now devel-oped and tested a system for warning traffic when semi-domestic reindeer are nearby the road. Tests on more than 700 reindeer over three consecutive winter seasons are promising.

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Abstract

This article focus is on the perceived impact that aquaculture industry has on coastal communities in Northern Norway. Here, aquaculture is key industry with natural, social and economic impacts. In natural resource management in general, identifying and monitoring the perceived social impacts can be a useful tool for local planning. In order to ensure the blue growth goals of the Norwegian government and avoid conflict and mistrust in the future, it is important to understand how both the general public and stakeholders perceive the aquaculture industry, how it affects them and its use of space in the coastal zone. Hence, we ask a) how do coastal communities perceive the aquaculture industry and b) is there a legitimacy gap between the blue growth strategies of the Norwegian Government and the public? In order to answer these questions, we lean on theories related to legitimacy and stakeholder's participation. Original data were collected from structured (N = 150) and semi-structured interviews (N = 10) in two coastal communities in Northern Norway (Alstahaug and Brønnøy). Our findings suggest that a legitimacy gap does exist between blue growth goals and fishers in the communities studied, while the general citizen holds a positive attitude towards aquaculture. Insights from this study are useful for local, regional and national decision makers with responsibility for natural resource policies and development efforts.

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Abstract

Understanding the factors that determine species’ resistance to environmental change is of utmost importance for biodiversity conservation. Here we investigated how the abundances of marshland species are determined by niche properties and functional traits. We re-surveyed 150 vegetation plots that were first surveyed in 1973 in order to explore species abundance changes over time. We found that the mean water level in the habitats of most studied species decreased significantly from 1973 to 2012. Nine of 17 target species were identified as abundance decreasing species and the other eight as abundance increasing species. The comparisons of seven plant characteristics (niche position water level, plant height, and five leaf traits) showed that the decreasing species had a significantly higher value of optimum water level and marginally significantly lower leaf N contents and specific leaf area (SLA) than those in increasing species. The stepwise regression analysis showed that optimum water level and leaf N were the best predictors of abundance changes of marsh plant species, as well as that the effect of optimum water level was stronger than that of leaf N. Our findings demonstrated that niche properties may be important for forecasting changes in wetland plant communities over time.

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Abstract

Questions Have species richness and composition in subarctic vegetation changed over the past ca. 90 years? Are compositional shifts linked to changes in land management or climate? Are observed changes associated with vegetation type, life form, or habitat preference? Location Rybachy and Sredny Peninsulas, NW Russia. Methods We resurveyed vegetation ca. 90 years after the first sampling in 1927–1930 to study changes in species richness, abundance and composition. Because of missing plot‐related environmental measurements we used a weighted averaging approach calculating relative changes in species‐specific optimum values for different environmental gradients represented by species indicator values to identify compositional change in relation to the environment. Changes in species composition were visualised using detrended correspondence analyses. Significances of observed changes in species richness and frequency were evaluated using restricted permutation tests. A χ2 test was used to test if observed changes in abundances were related to species’ life form and habitat preferences. Results Species composition has changed significantly over the past ca. 90 years, as indicated by significant changes in species’ frequencies and values of optima for the environmental gradients temperature, moisture, nutrients and light. Species richness decreased significantly, in particular in nitrophilous and wet growing vegetation. Species typical for grazed grasslands and meadows and species of wet habitats became less abundant, while dwarf shrubs and forest species increased. Conclusions Land abandonment, in combination with climate change, is likely to have caused the observed changes in the subarctic vegetation of NW Russia. Shifts in the species dominance ratios and interspecific competition (e.g. for reallocated nutrients) after land abandonment may have been promoted by the subsequent change towards a warmer climate, facilitating the regrowth of previously open meadows with grazing‐intolerant tall herbs, forest herbs and dwarf shrubs. This study illustrates clearly the long‐term effects of land‐use change, the consequences of which are still visible even after almost one century in the subarctic.