Arctic lakes disappear
Ecological consequences of climate change visible in the far northRead out
They have been around for thousands of years, but now they have disappeared: the flat sweeping freshwater lakes of the summer Arctic. Polar researchers have now observed the dehydration of more and more of these lakes and see this as a warning sign of the effects of climate change.
Marianne Douglas, Professor of Earth Sciences at the University of Alberta and John Smol, Professor of Biology at Queens University, have been exploring the unique chemistry and life of the Arctic lakes for more than 24 years. Their long-term data from a total of 40 lakes thus gives the longest systematic insight into features and changes in wetlands in the Arctic. In recent years, the researchers have noted a worrying trend: the water levels fell and chemical changes pointed to increased evaporation and warmer temperatures. Finally, in July 2006, several lakes completely dried up.
"It was quite shocking to see some of our largest lakes drop dry early in the summer, " explains Douglas. The environmental consequences of these changes are, according to the researchers, considerable and could be felt throughout the Arctic ecosystem. Dehydration deprives many waterfowl from their feeding and breeding grounds, and thins out the invertebrate populations of animals that feed on numerous insectivores. The drinking water supply of Arctic wildlife is also endangered.
"These superficial water surfaces are so important because they are often hotspots of biodiversity and productivity for microorganisms, plants and animals in this extreme habitat, " says Douglas.
(University of Alberta, 04.07.2007 - NPO) Display