|Horní hranice lesa v Krkonoších – jaké faktory podmiňují její změny v čase?|
|Treeline ecotone in the Krkonoše Mts – which factors influence its changes over time?|
|Mgr. Václav Treml; Michal Dobíhal; Lucie Kupková; Jakub Lysák; Markéta Potůčková|
|The treeline ecotone in the Krkonoše Mts is in its|
upper part limited by a combination of low summer
temperature and high winter biomass loss, a consequence
of intense wind flow and high snow loads.
The extent of summit alpine areas has been gradually
reduced over the last decades due to upward advance
of tree stands represented mostly by densification of
treeline ecotone. The upward shift of treeline ecotone
was triggered by termination of mountain farming at
the end of 19th century and the beginning of the 20th
century, resulting in establishment and gradual closing
of Norway spruce stands. Since 1980s, the growth
of Norway spruce has substantially accelerated leading
to faster closing of already established tree stands.
We assume that the trend of treeline ecotone densification
will continue, however the upper margin of
treeline ecotone is not expected to move substantially
further, thanks to environmental limits imposed by
high winter biomass losses.