Webpages tagged with «UiO»

Here we look at life-history adaptation in the arctic charr in a high mountain environment with a particular emphazis on its life history strategies. As this is a marginal environment with regard to the number and variability of degree-days (i.e. the temperature sum), and the length and variability of the feeding season, the charr must trade-off energetic requirements to growth and gonad allocation, and potentially adopt a bet-hedging strategy. Thus, alternative life-history strategies may evolve in such harsh environments as compared to the founder population which exists in a very divergent lowland environment.

Here we look at life-history adaptation in the arctic charr in a high mountain environment with a particular emphazis on its life history strategies. As this is a marginal environment with regard to the number and variability of degree-days (i.e. the temperature sum), and the length and variability of the feeding season, the charr must trade-off energetic requirements to growth and gonad allocation, and potentially adopt a bet-hedging strategy. Thus, alternative life-history strategies may evolve in such harsh environments as compared to the founder population which exists in a very divergent lowland environment.

Here we look at life-history adaptation in the arctic charr in a high mountain environment with a particular emphazis on its life history strategies. As this is a marginal environment with regard to the number and variability of degree-days (i.e. the temperature sum), and the length and variability of the feeding season, the charr must trade-off energetic requirements to growth and gonad allocation, and potentially adopt a bet-hedging strategy. Thus, alternative life-history strategies may evolve in such harsh environments as compared to the founder population which exists in a very divergent lowland environment.

Here we look at life-history adaptation in the arctic charr in a high mountain environment with a particular emphazis on its life history strategies. As this is a marginal environment with regard to the number and variability of degree-days (i.e. the temperature sum), and the length and variability of the feeding season, the charr must trade-off energetic requirements to growth and gonad allocation, and potentially adopt a bet-hedging strategy. Thus, alternative life-history strategies may evolve in such harsh environments as compared to the founder population which exists in a very divergent lowland environment.

About 370 species of macromycetes have been identified in the area during sporadic visits since 1972. The main focus has been on Basidiomycota, especially the agarics. Many genera, for example most dark spored agarics, are still poorly known and many more species than those identified occur in the area. Part of the project has been to disclose connections between fungal species and vegetation types by means of studying the funga in a set of permanent plots

Lake Flakavatn, 6 km north-northeast of Finse, was visited by the limnologist Kaare M. Strøm in August 1933. He did a geomorphological survey of the watershed, he made a bathygraphical map of the lake, and he recorded some basic limnological observations which are the foundation of our continuing work in this lake. The present project in lake Flakavatn is part of a long-term program covering lakes with similar limnological properties but located under different climatic conditions within Norway - "The Limnology of Ultraoligotrophic Lakes". Students, post-docs and colleagues from various disciplines are taking part in the Flakavatn project - emerging and experienced scientists from all subdusciplines are welcome!

Lake Flakavatn, 6 km north-northeast of Finse, was visited by the limnologist Kaare M. Strøm in August 1933. He did a geomorphological survey of the watershed, he made a bathygraphical map of the lake, and he recorded some basic limnological observations which are the foundation of our continuing work in this lake. The present project in lake Flakavatn is part of a long-term program covering lakes with similar limnological properties but located under different climatic conditions within Norway - "The Limnology of Ultraoligotrophic Lakes". Students, post-docs and colleagues from various disciplines are taking part in the Flakavatn project - emerging and experienced scientists from all subdusciplines are welcome!

Mycorrhizal symbiosis is crucial for most woody plants, especially in harsh environments such as the alpines. This project uses the perennial herb Bistorta vivipara as a model species to study ectomycorrhizal community ecology. The main aim is to reveal which factors (biotic or abiotic) that influence the fungal community structure. The variation in community structure is analyzed along various ecological gradients, including a primary successional gradient towards Blåisen. Pyrosequencing is used to analyze the fungal communities associated with the rootsystems of B. vivipara, a method that yield both quantitative and qualitative data about the communities.

Pyrosequencing is applied for the study of plankton and protist diversity in lake Finsevatn. This lake has been influenced by human activity, particularly since the tourism came to this high-mountain location with the opening of the Oslo-Bergen railway in 1909. Scientific investigations since 1986 have revealed the diversity of the lake's phytoplankton by microscopy, but new technology supplies a much more diverse picture involving microbial parasites and previously unknown protists - some with relatives in marine environments - see Bråte et al. (2010), Shalchian-Tabrizi et al. (2011).

About 370 species of macromycetes have been identified in the area during sporadic visits since 1972. The main focus has been on Basidiomycota, especially the agarics. Many genera, for example most dark spored agarics, are still poorly known and many more species than those identified occur in the area. Part of the project has been to disclose connections between fungal species and vegetation types by means of studying the funga in a set of permanent plots

Populations of small rodents, especially lemmings in alpine and arctic environments, show extreme fluctuations in density from year to year and their cyclic dynamics have interested ecologists for nearly a century. Population dynamics of lemmings are, however, difficult to study because densities are often very low and the spatial distribution among different habitats depends highly on season and population density. This limits the usefulness of traditional studies of population dynamics in fixed trapping grids covering a limited area. In this project we look at seasonal and multi-annual patch occupancy dynamics of lemmings and other small rodents over several square kilometers and relate this to habitat characteristics and population density.

Here we look at life-history adaptation in the arctic charr in a high mountain environment with a particular emphazis on its life history strategies. As this is a marginal environment with regard to the number and variability of degree-days (i.e. the temperature sum), and the length and variability of the feeding season, the charr must trade-off energetic requirements to growth and gonad allocation, and potentially adopt a bet-hedging strategy. Thus, alternative life-history strategies may evolve in such harsh environments as compared to the founder population which exists in a very divergent lowland environment.