ALPECOLE
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Alpine plant biodiversity

Global change


 

Alpine plant species in general, and especially the orophytes, are adapted to the harsh environmental conditions in the alpine life zone. In the future, climatic conditions in this zone will most probably change due to global climate warming. The increase of the mean annual temperature would lead to an alleviation of environmental factors, which mainly determine the distribution of vascular plant species, namely temperature and growing season length. The question is, how plants will respond to the changed climatic conditions. Will they adapt to the new situation, will they migrate to more convenient regions, or will they simply become extinct? The first evidence of migration was reported by Hofer (1992) and Grabherr et al. (1994), who showed that the species numbers on mountain summits in the Central Alps has increased during the last 100 years, suggesting that elevated temperatures have allowed species from lower altitudes to climb upwards. Alternatively, global climate warming could also cause a loss of specific habitats and an increase of competition in the alpine life zone thereby leading to a reduction of species richness. However, these are speculations. Today, we do not yet have the data required to accurately predict future alpine plant diversity.

increase of species number on Alpine summits

1 - Change in species richness on 14 peaks of the Bernina Area (Switzerland) between 1905 and 1985. In 12 peaks - all situated in the nival belt between 2900 and 3300 m - the number of species has increased significantly.

 

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29 August 2011
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