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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.

2015

Sammendrag

In boreal ecosystems, traditionally diverse agricultural landscapes were composed of a mosaics of intensively used fields (monocultures), low intensively used vegetation types such as semi-natural grasslands and forests. The landscapes are now changing to less diverse landscapes of fields and forests. Agricultural landscapes are potential suppliers of ecosystem services such as aesthetic, genetic, pollination and agricultural production. The ongoing process of landscape change will influence provision of ecosystem services but little is known about in which directions. The aim of this project is to shed light on potential outcomes of the land-use changes on ecosystem services in agricultural boreal landscapes.

Sammendrag

Predicting how human induced vegetation changes affect ecosystems and their biological communities is one of the most urgent tasks in ecology. In Norwegian lowlands one of the main threats to biodiversity is abandonment of low intensive land-use areas. Effects of changed land-use on vegetation are generally made by assessing the effect on the number of species as indicators of biodiversity. However, community structure changes and ecosystem processes are not necessarily well described by this biodiversity indicator only. Functional trait responses might better predict structures and processes than species richness. Therefore, studies of functional traits and biodiversity indexes of these might provide deeper insight. In addition, to predict reliable future vegetation changes, multifactorial determinants have to be considered as vegetation is not driven by one determinant only.

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Sammendrag

Aim Previous research on how climatic niches vary across species ranges has focused on a limited number of species, mostly inv asive, and has not, to date, been very conclusive. Here we assess the degree of niche conservatism between distant populations of native alpine plant species that have been separated for thousands of years. Location European Alps and Fennoscandia. Methods Of the studied pool of 888 terrestr ial vascular plant species occurring in both the Alps and Fennoscandia, we used two complementary approaches to test and quantify climatic-niche shifts for 31 species having strictly disjunct populations and 358 species having either a contiguous or a patchy distribution with distant populations. First, we used species distr i- bution modelling to test for a region effect on each species’ climatic niche. Second, we quantified niche overlap and shifts in niche width (i.e. ecological amplitude) and position (i.e. ecological optimum) within a bi-dimensional climatic space. Results Only one species (3%) of the 31 species with str ictly disjunct populations and 58 species (16%) of the 358 species with distant popula- tions showed a region effect on their climatic niche. Niche overlap was higher for species with strictly disjunct populations than for species with distant populations and highest for arctic–alpine species. Climatic niches were, on average, wider and located towards warmer and wetter conditions in the Alps. Main conclusion Climatic niches seem to be generally conserved between populations that are separated between the Alps and Fennoscandia and have probably been so for 10,000–15,000 years. Therefore, the basic assumption of species distribution models that a species’ climatic niche is constant in space and time – at least on time scales 10 4 years or less – seems to be largely valid for arctic–alpine plants.

2014