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Forests Are Reclaiming Norwegian Mountain Slopes
Olsson, E.G.A., Austrheim, G. and Grenne, S.N.  2000.  Landscape change patterns in mountains, land use and environmental diversity, Mid-Norway 1960-1993.  Landscape Ecology 15: 155-170.

Mountains in Norway have been used for supporting domestic livestock for the past 4,000 years, especially since the 16th century, which saw the development of the summer farming system there.  The authors speculate that this activity reduced forested areas, but that changes in farming practices are now allowing the forests to return.

What was done
The authors studied two valleys, Budal and Sjodal, in Mid-Norway that they say are representative of core areas of the Norwegian summer farming mountain ecosystem, which "is shaped by human activities rooted in pre-history."  Specifically, they quantified changes in land use and landscape patterns in the two areas over the period 1960-1993.

What was learned
Grasslands and heathlands that had long dominated the mountain slopes of the two study areas are, in the words of the authors, "today decreasing due to forest invasion," which they say is characterized by "the spread of subalpine woodlands, and a raised treeline."

What it means
The authors feel that the expansion of the subalpine woodlands "is primarily related to changes in the human use of those areas," which in their estimation "are here much more influential than possible effects of climate change."  In this conclusion we basically concur.  However, it is also possible that the ongoing rise in the air's CO2 concentration may be playing a role in the forests' comeback as well.  In any event, the ongoing increase in the presence of forests upon the mountains of Norway is but one more manifestation of the profusion, or spreading, of woody species over the face of the planet that is helping to slow the rate of rise of the atmosphere's CO2 concentration (see our Editorial Let's Get Serious?  Let's Get Real!).

Reviewed 25 October 2000