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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.

2024

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Abstract

Herbivores play a crucial role in shaping tundra ecosystems through their effects on vegetation, nutrient cycling, and soil abiotic factors. Understanding their habitat use, co-occurrence, and overlap is therefore essential for informing ecosystem-based management and conservation. In the High Arctic, only a marginal proportion of the land area is vegetated, and climate change is impacting herbivore population sizes and their habitats. In this study, we assessed the spatial habitat overlap of a vertebrate herbivore community based on: 1) regional predictive summer habitat suitability models for the resident Svalbard reindeer (Rangifer tarandus platyrhynchus), resident Svalbard rock ptarmigan (Lagopus muta hyperborea), and the migratory pink-footed goose (Anser brachyrhynchus), and 2) presence of fecal pellets, reflecting the annual habitat use of reindeer, ptarmigan, and geese, including the pink-footed goose and barnacle goose (Branta leucopsis). Our findings revealed that only small proportions of the available land cover (~ 12516 km2; all land area excluding glaciers and freshwater) are suitable for each of the species (habitat suitability [HS] > 0.5): reindeer (22%), ptarmigan (11%), and pink-footed goose (4%). Overlapping suitable habitat [HS > 0.5] for reindeer and goose accounted for only 3% of the total vegetated area (~ 8848 km2) and was primarily found in heath and moist habitats dominated by mosses, graminoids, and herbaceous plants. The overlapping suitable habitat for reindeer and ptarmigan covered 8% of the vegetated area, predominantly in higher elevation ridges with vegetation on drier substrates. The shared habitat for ptarmigan and goose, and all three species of herbivores, was less than 1% of the vegetated area. Additionally, an assessment of fecal pellets suggested that the highest overlap in habitat use among reindeer and goose occurred in bird cliff moss tundra, followed by moss tundra and heath habitats. The small proportion of the vegetated area suitable for all three herbivores indicates a high degree of habitat differentiation. Therefore, different habitats need to be considered for the management and conservation of resident and migratory herbivore species in this High Arctic Archipelago. Moreover, our results underscore the importance of the small but productive parts of the landscape that were used by all herbivores. Goose, habitat suitability, management, ptarmigan, reindeer

2023

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Abstract

The aim was to explore the impact of temperature during seed development on yield performance and seed quality in faba bean when grown at cool temperatures representative for high latitude regions. Two varieties, an early and a medium late maturing, were grown in climate chambers with three temperature regimes (day/night temperatures of 14°C/12°C, 19°C/12°C, and 24°C/12°C) from onset of flowering to maturation. Yield components were recorded, and the accumulation of protein, starch, and low molecular weight carbohydrates including the raffinose family oligosaccharides was followed during the accumulation phase until physiological maturity. The lower temperature regimes strongly delayed pod and seed development compared with 24°C/12°C. Temperature affected the number of pods per plant for the upper node group. Plants grown at 19°C had the highest total dry seed weight compared with plants grown at 14°C and 24°C. Temperature per se did not influence the content of starch, protein, and low molecular weight carbohydrates, while their accumulation followed the moisture content in the seed, and thus the seed development stage. The content of raffinose family oligosaccharides increased sharply when the seed moisture dropped below 70% and leveled off at about 40% and 50% moisture for verbascose and stachyose, respectively, coinciding with physiological maturity. The results provide more knowledge about the seed maturation and accumulation in faba bean under low temperatures, important for cultivation under high latitude regions.

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Abstract

Arctic tundra vegetation is affected by rapid climatic change and fluctuating herbivore population sizes. Broad-billed geese, after their arrival in spring, feed intensively on belowground rhizomes, thereby disturbing soil, mosses, and vascular plant vegetation. Understanding of how springtime snowmelt patterns drive goose behavior is thus key to better predict the state of Arctic tundra ecosystems. Here, we analyzed how snowmelt progression affected springtime habitat selection and vegetation disturbance by pink-footed geese (Anser brachyrhynchus) in Svalbard during 2019. Our analysis, based on GPS telemetry data and field observations of geese, plot-based assessments of signs of vegetation disturbance, and drone and satellite images, covered two spatial scales (fine scale: extent 0.3 km2, resolution 5 cm; valley scale: extent 30 km2, resolution 10 m). We show that pink-footed goose habitat selection and signs of vegetation disturbance were correlated during the spring pre-breeding period; disturbances were most prevalent in the moss tundra vegetation class and areas free from snow early in the season. The results were consistent across the spatial scales and methods (GPS telemetry and field observations). We estimated that 23.4% of moss tundra and 11.2% of dwarf-shrub heath vegetation in the valley showed signs of disturbance by pink-footed geese during the study period. This study demonstrates that aerial imagery and telemetry can provide data to detect disturbance hotspots caused by pink-footed geese. Our study provides empirical evidence to general notions about implications of climate change and snow season changes that include increased variability in precipitation.