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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.

2010

2009

To document

Abstract

There is limited knowledge on the brown bear (Ursus arctos) populations in the neighboring national parks Lemmenjoki in Finland and Øvre Anárjohka in Norway. Lemmenjoki is the largest National Park in Finland with its 2850 km2, while Øvre Anárjohka National Park is about 1390 km2. Studies of the bear population within this area are complicated by the fact that the area is one of the largest roadless and remote areas in Northern Europe. In this study we have applied the hair trap technique to monitor the brown bear populations of Øvre Anárjohka and Lemmenjoki during July and August of 2009.The study was limited to 850 km2 (34 hair traps in a 5 x 5 km grid, 20 % of the total area of the National Parks). The result was a total of 33 hair samples collected in the study period of 8 weeks (4 renewals of scent lure), which is on average 0.5 hair samples per trap/month. DNA from bears was detected in 28 of the samples (85%). We were able to analyze a complete genetic profile for 23 samples. Nine samples from the terrain were also included in the study, and in total we have identified 6 different bears within the study area. The average brown bear density for the study area was found to be 0.07 bears/10 km2, which is 3 times lower than in the neighboring population in Pasvik-Inari-Pechenga. The three bears identified at the Norwegian side of the border (two females and one male) had been previously detected in Øvre Anárjohka in Norway during 2005-2008, while the three males that were solely on the Finnish side had not been registered before. Comparison with previous monitoring data in Norway confirm that Øvre Anárjohka in Norway might be a low-density reproduction site for brown bears, while the study area in Lemmenjoki in Finland is sparsely populated by a few males. We recommend that a larger study should be performed in the area.

To document

Abstract

Comparisons of individual DNA-profiles between different laboratories require that the data can be standardized. In this study, we compared DNA profiles of brown bears (Ursus arctos) from Sweden with DNA profiles of Norwegian brown bears. Brown bear samples from Sweden were analyzed at Laboratoire d’Ecologie Alpine (LECA) in France, while the samples collected in Norway were analyzed in the DNA laboratory at Bioforsk Svanhovd. In April 2008, DNA from 38 different bears were analyzed both at LECA in France and at Bioforsk Svanhovd in Norway, which allowed to estimate a first calibrations keys and normalise the data. In this study, new calibration keys were determined in order to make the genotypes from Norwegian bears comparable with the whole Swedish bear genetic database. The comparison based on the new calibration key included 163 individuals from Norway (time period 2005-2009) and gave 42 matches with individuals from the database for Swedish brown bears (time period 2001-2009). Marker MU59 did not function well in this calibration and additional analyses are needed to sort out the problems with this marker.

2008

2007

2006

Abstract

The effect of zinc on soil nitrification and composition of the microbial community in soil was investigated using a full factorial experiment with five zinc concentrations and four levels of biological complexity (microbes only, microbes and earthworms (Eisenia fetida), microbes and Italian ryegrass (Lolium multiflorum var. Macho), and microbes, ryegrass and earthworms). After 6 weeks of exposure, the activity of soil nitrifying bacteria was measured and the microbial community structure was characterized by phospholipid fatty acid (PLFA) analysis. Soil nitrification and several PLFA markers were significantly influenced by either zinc addition and/or the presence of earthworms or ryegrass, and one of the most pronounced changes was the increase of fungi and decrease of bacteria with increasing concentrations of zinc. Of particular interest, however, was the potential interaction between the presence of plants and/or earthworms and the effect of zinc, which the factorial study design allowed us to explore. Such an effect was observed in two cases: Earthworms reduced the positive effect of zinc on the fungal biomass (ANOVA, p = 0.03), and the effect of earthworms on the soil nitrification activity depended on zinc concentration (ANOVA, p < 0.05). The effect of earthworm presence was not very large, but it does show that multispecies tests might give information about metal toxicity, or bioavailability that cannot be predicted from single-species tests. (c) 2006 Elsevier Ltd. All rights reserved.

1995