Demographic Structure of Cypripedium calceolus L. Populations in the European Part of Russia under Climate Change

The paper presents recent data on the demographic structure and population size of C. calceolus in European Russia. The assessment of the species distribution and population size is based on the global classification of terrestrial ecoregions. The long-term dynamics of the number and age structure (150 populations) of C. calceolus were revealed for the 20-year research period, 1997–2020. It has been reliably determined that the number of reproductive plants is positively related to temperature indicators, while the number of pre-reproductive individuals depends on humidity factors and negatively on temperature. Three types of basic age spectra were identified: (1) centered 3:10:47:40 (juvenile (j): immature (im): virginal (v): reproductive (g)), the most common in the European part of the Russian Federation (RF); (2) bimodal 15:26:33:26 (j:im:v:g), mainly found in the western regions; (3) right-hand 0:3:13:82:2 (j:im:v:g:s), which steadily appears in the continental climate of eastern regions of European Russia. The current baseline spectra of C. calceolus populations differ from the baseline spectrum of the species given in the 20th century. The base spectra significantly depends on ecological-phytocoenotic plant community structure and abiotic features of habitats, it shown using the ecological indicator values.