In this article we present and discuss the main factors that threaten natural populations of Cypripedium calceolus (lady's slipper orchid) in Europe, and we propose conservation strategies and directions for protective actions of its population on a regional scale. European C. calceolus populations have decreased significantly in the last two decades, in both number and size. A key result of the present study is an evaluation of the effectiveness of the Natura 2000 network across the European Union (EU) countries. Northern and/or mountainous countries present higher percentages of potentially suitable areas within the Natura 2000 network. Finland and the United Kingdom are the exceptions to this rule. It is predicted that, due to global warming, the coverage of niches suitable for C. calceolus will decrease in countries in which now-healthy colonies exist. However, as plant species can occur in micro-sites with suitable environmental conditions (e.g., microclimate, vegetation, soil factors) which cannot be predicted as suitable at coarser spatial resolutions, conservation efforts should be focused on management of local healthy populations. For the effective protection of C. calceolus in Natura 2000 sites, the participation of experts in botany, including orchid biology, is necessary at several stages.

Association P P 5 N C Excelsior Timisoara branch 310465 Timisoara Romania

Berliner Allee 191 D 13088 Berlin Germany

Department of Biodiversity Research Global Change Research Institute AS CR Bělidla 4a 603 00 Brno Czech Republic

Department of Botany Institute of Environmental Biology University of Wrocław Kanonia Street 6 8 50 328 Wrocław Poland

Department of Botany Naturalis Biodiversity Center 2300 RA Leiden The Netherlands

Department of Forest and Natural Environment Sciences International Hellenic University GR 66132 Drama Greece

Department of Geobotany and Plant Ecology Faculty of Biology and Environmental Protection University of Łódź Banacha 12 16 90 237 Łódź Poland

Institute for Environmental Studies Faculty of Science Charles University Benátská 2 CZ 12900 Prague Czech Republic

Institute of Botany and Botanical Garden Faculty of Biology University of Belgrade Takovska 43 11000 Belgrade Serbia

Komarov Botanical Institute of the Russia Academy of Sciences 197376 Saint Petersburg Russia

Lower Silesian Ecological Club Piłsudskiego Street 74 PL 50 020 Wrocław Poland

Nature Conservation Agency of the Czech Republic Kaplanova 1931 1 CZ 14800 Prague Czech Republic

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