Species frequency or rarity and the categorisation of plant species using biological traits have been important subjects in ecological studies during the last years. The combined analysis of species rarity and life history traits can lead to a better understanding of the processes making species become rare or threatened within the changing landscape of Central Europe. Today, many different databases comprise floristic data, data on species performance, data on habitat distribution or species trait data, but these data sources have rarely been combined. The present thesis shows that the combination of different existing databases can reveal valuable information on different aspects of species or habitat rarity (Chapter 2), on the use and ecological relevance of indicator traits (Chapter 3 and 4) and on mechanisms that make species become threatened or leading to species rarity in today?s landscape (see Chapter 5). This information and proposed subsequent analyses (Chapter 6) may lead to a better understanding of vegetation dynamics and restoration measures.weiterlesen