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Rapid, landscape scale responses in riparian tundra vegetation to exclusion of small and large mammalian herbivores
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
Productive tundra plant communities composed of a variety of fast growing herbaceous and woody plants are likely to attract mammalian herbivores. Such vegetation is likely to respond to different-sized herbivores more rapidly than currently acknowledged from the tundra. Accentuated by currently changing populations of arctic mammals there is a need to understand impacts of different-sized herbivores ...
Population dynamics of tundra voles in relation to configuration of willow thickets in southern arctic tundra
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
The areal extent and conWguration of thickets of
willow shrubs are currently changing in the Arctic both as an eVect of global warming and changed browsing pressure of reindeer. These changes have been predicted to impact the distribution and abundance of wildlife species relying on willow thickets as habitat. We assessed the relation between variables quantifying willow thicket configuration
and ...
Red fox takeover of arctic fox breeding den : an observation from Yamal Peninsula, Russia
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
Here, we report from the first direct observation of a red fox (Vulpes vulpes) intrusion on an arctic fox (Vulpes lagopus) breeding den from the southern Arctic tundra of Yamal Peninsula, Russia in 2007. At the same time, as a current range retraction of the original inhabitant of the circumpolar tundra zone the arctic fox is going on, the red fox is expanding their range from the south into arctic ...
Intrapopulation variability shaping isotope discrimination and turnover : experimental evidence in Arctic Foxes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
Tissue-specific stable isotope signatures can provide insights into the trophic ecology of consumers and their roles in food webs. Two parameters are central for making valid inferences based on stable isotopes, isotopic discrimination (difference in isotopic ratio between consumer and its diet) and turnover time (renewal process of molecules in a given tissue usually measured when half of the tissue ...
The importance of willow thickets for ptarmigan and hares in shrub tundra : the more the better?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
The ghost of development past : the impact of economic security policies on Saami pastoral ecosystems
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
To ensure economic viability over time, any efforts to meet the Millennium Development
Goals need to reconcile conservation with development interventions. Particularly, in marginal and risk prone areas erosion of resilience could make production systems more susceptible to environmental risks that compromise the economic security. By longitudinal analyses of long-term data records we investigated
the ...
Future changes in the supply of goods and services from natural ecosystems: prospects for the European north
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09)
Humans depend on services provided by ecosystems, and how services are affected by climate change is increasingly
studied. Few studies, however, address changes likely to affect services from seminatural ecosystems. We analyzed ecosystem goods and
services in natural and seminatural systems, specifically how they are expected to change as a result of projected climate change during
the 21st ...
How spatial variation in areal extent and configuration of labile vegetation states affect the riparian bird community in Arctic Tundra
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
The Arctic tundra is currently experiencing an unprecedented combination of climate change, change in grazing pressure by large herbivores and growing human activity. Thickets of tall shrubs represent a conspicuous vegetation state in northern and temperate ecosystems, where it serves important ecological functions, including habitat for wildlife. Thickets are however labile, as tall shrubs respond ...
Shedding new light on the diet of Norwegian lemmings: DNA metabarcoding of stomach content
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
Lemmings are key herbivores in many arctic food webs, and their population dynamics have major impacts on the functioning of tundra systems. However, current knowledge of lemming diet is limited, hampering evaluation of lemming–vegetation interactions. This lack of knowledge is mainly due to methodological challenges, as previously used microhistological methods result in large proportions of poorly ...
Local and regional determinants of colonisation-extinction dynamics of a riparian mainland-island root vole metapopulation
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013)
The role of local habitat geometry (habitat area and isolation) in predicting species distribution has become an increasingly
more important issue, because habitat loss and fragmentation cause species range contraction and extinction. However, it
has also become clear that other factors, in particular regional factors (environmental stochasticity and regional population
dynamics), should be taken ...