Extinct and endangered species in the vascular plant flora of Strzelce Opolskie (Southern Poland)

Symptoms of anthropogenic changes in the vascular plant flora include the spread of some species groups and the extinction of others. Also habitat condition changes (eutrophication, pollution etc.) and biodiversity loss (at a regional, national and even continental scale) should be mentioned. Numerous papers with rare plant species localities and endangered habitats have been published but the extinction processes and scale of this phenomenon in urban areas where environmental conservation is crucial, are not often analysed. The aim of the present study is to estimate species loss in the vascular plant flora of the town Strzelce Opolskie (Chełm, Silesian Upland) on the basis of the floristic literature and botanical surveys carried out from 2011 to 2013. A comparison has been made between the list of species reported up to 1945 and those species currently occurring in the study area. As a result, a list of 99 species included in the red list of plants of Opole and Silesian voivodeships is presented. Among this group, 45 species are not confirmed after 1945. Numerous extinct and endangered species are from families: Orchidaceae (8 species), Cyperaceae (7 species), Ranunculaceae (7 species) and Lamiaceae (6 species). Strongly represented are species associated with the communities of Festuco-Brometea and Querco- Fagetea classes. From the species presented, 18 species are included in "Red List of Vascular Plants of Poland" (MIREK ET AL. 2006). It was found that the extinct species represent about 7% of Strzelce Opolskie vascular plant flora. It is a focus point for local authorities to protect botanically valuable areas. Actually, the only Miejski Park is under the conservator's protection and there are few individual trees protected due to their age or size.