University of Iceland
Natural variation and biodiversity
Nature shows considerable variation in space and time and this variation does profoundly affect populations. In highly developed countries this variation is often masked by factors influenced by humans and most of the time, natural variation and human influence interact at different scales and can be challenging to separate. Iceland has still some of the lowest human population density on earth and shows exceptional variation in climate and geology. It has a northerly position where cold and warm sea currents meet and lies on the North Atlantic ridge where the North american and the Eurasian tectonic plates come together. Capitalizing on these unique conditions we have carried out a range of projects which help us understand the role of natural processes in regulating populations at large spatial and temporal scales.
A schematic diagram of key connections between the physical world, land-use and the biodiversity components which have been a focus of our studies
Iceland shows exceptionally high habitat diversity, mostly owing to its unique geology and variable climate. Much of our work has focused on identifying variation in the distribution and abundance of bird populations across different habitats and the demographic consequences of occupying different habitats. The diversity of birds and invertebrates follow vegetation patterns and hydrology strongly and variation in habitat quality across Iceland also relates to migration patterns within populations.
Geology is underlying variation in habitat quality, everywhere. However, the links between geology and biodiversity remain poorly understood at a global level, probably because these effects are often masked by human disturbances. By linking studies of individual species, ecosystem monitoring and large-scale distribution patterns we have made steps in uncovering the role of geology in driving variation in abundance and demography of birds. Among other things we have shown, in close collaboration with prof. Olafur Arnalds at the Icelandic Agricultural university, that the rates of deposition of volcanic dust affect distribution patterns of birds strongly and positively through ecosystem recharge of nutrients. We have also shown that volcanic eruptions have a strong, negative short-term effect on productivity in bird populations.
Weather and Climate
Several studies have focused on links between variation in weather and population processes in birds. These have for example showed how annual variation in spring temperature relates to breeding success of waders, how temperature affects timing of migration, and how temperature variation across Iceland affects productivity of geese and how rare weather events impact population size in Common Eiders (in close collaboration with Dr. Jon Einar Jonsson at the Snæfellsnes Research centre). Studies on weather and climate are a prime example of how natural and anthropogenic processes can interact.