| Summary: | The dissertation thesis contains six original papers dealing with an influence of isolation, fragmentation and habitat loss on present cultural and urban landscape. Conclusions are based from studies of one species to those of whole butterfly communities. The first two papers deal with autecology of The Hermit (Chazara briseis) from its last viable population in the Czech Republic. During the last 20 years, it retreated from the republic, and recently it is classified as nearly extinct. The papers point to reasons of the rapid decrease: specialized life strategy and habitat losses. Due to high mortality of long-lived females, this species requires the compensation by high population size in large habitats. The next paper refers to habitat requirements of The Hermits' caterpillars. Local habitat conditions at study sites were noticeably similar to the conditions at German localities, at which this species is now practically extinct. Following two papers study an influence of urbanization on butterfly communities in 25 Prague reserves and parks. The first paper points to diversity changes during 30 years and their causes. Average number of species per site remained the same, but there were detected changes in species composition. Remarkable switching of species composition was observed mainly at large...
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