Anthropogenic sites maintain the last individuals during the rapid decline of the lowland refugium of the alpine-arctic plant Pulsatilla vernalis (L.) Mill

摘要

The Tuchola Forest (UNESCO MaB Biosphere Reserve) in Central European Lowlands is an area where the relict populations of the alpine-arctic plant Pulsatilla vernalis (L.) Mill. have survived since glacial periods. However, during the last several years rapid extinction of the species has been observed in this area. The aim of the study was the estimation of Pulsatilla vernalis extinction rate in the Tuchola Forest as well as the description of current refugial habitats. The results show that in approximately last 10 years (from 2004-2008 to 2015) 31% of the previously noted localities became extinct. The decrease in the species abundance (measured by the number of rosettes) affected almost all of still existing populations. The total decrease in the number of rosettes for the whole study area was 70%. In 2015, 88% rosettes grew within or at a distance smaller than ten meters from the anthropogenic habitats such as roads and slopes of railway embankments or lining them ditches. Based on the estimation of P. vernalis extinction rate we concluded that the analysed refugium is disappearing and if the trend will continue for the next few years, the species will probably vanish from the majority of the known localities.