The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Default user image.

Margareta Johansson

Researcher

Default user image.

Effects on the structure of arctic ecosystems in the short- and long-term perspectives

Author

  • Terry V. Callaghan
  • Lars Olof Björn
  • Yuri Chernov
  • Terry Chapin
  • Torben Christensen
  • Brian Huntley
  • Rolf A. Ims
  • Margareta Johansson
  • Dyanna Jolly
  • Sven Jonasson
  • Nadya Matveyeva
  • Nicolai Panikov
  • Walter Oechel
  • Gus Shaver
  • Heikki Henttonen
Show all

Summary, in English

Species individualistic responses to warming and increased UV-B radiation are moderated by the responses of neighbors within communities, and trophic interactions within ecosystems. All of these responses lead to changes in ecosystem structure. Experimental manipulation of environmental factors expected to change at high latitudes showed that summer warming of tundra vegetation has generally led to smaller changes than fertilizer addition. Some of the factors manipulated have strong effects on the structure of Arctic ecosystems but the effects vary regionally, with the greatest response of plant and invertebrate communities being observed at the coldest locations. Arctic invertebrate communities are very likely to respond rapidly to warming whereas microbial biomass and nutrient stocks are more stable. Experimentally enhanced UV-B radiation altered the community composition of gram-negative bacteria and fungi, but not that of plants. Increased plant productivity due to warmer summers may dominate food-web dynamics. Trophic interactions of tundra and sub-Arctic forest plant-based food webs are centered on a few dominant animal species which often have cyclic population fluctuations that lead to extremely high peak abundances in some years. Population cycles of small rodents and insect defoliators such as the autumn moth affect the structure and diversity of tundra and forest-tundra vegetation and the viability of a number of specialist predators and parasites. Ice crusting in warmer winters is likely to reduce the accessibility of plant food to lemmings, while deep snow may protect them from snow-surface predators. In Fennoscandia, there is evidence already for a pronounced shift in small rodent community structure and dynamics that have resulted in a decline of predators that specialize in feeding on small rodents. Climate is also likely to alter the role of insect pests in the birch forest system: warmer winters may increase survival of eggs and expand the range of the insects. Insects that harass reindeer in the summer are also likely to become more widespread, abundant and active during warmer summers while refuges for reindeer/caribou on glaciers and late snow patches will probably disappear.

Department/s

  • Molecular Cell Biology
  • Dept of Physical Geography and Ecosystem Science

Publishing year

2004

Language

English

Pages

436-447

Publication/Series

Ambio: a Journal of Human Environment

Volume

33

Issue

7

Document type

Journal article review

Publisher

Springer

Topic

  • Physical Geography
  • Biological Sciences

Keywords

  • terrestrial ecosystems climate change ultraviolet radiation

Status

Published

ISBN/ISSN/Other

  • ISSN: 0044-7447