Zur Phytodiversität städtischer Rasen in Braunschweig

Urban lawns are a very young phenomenon in cultural history as well as in vegetation history. Their phytodiversity is investigated using Braunschweig as an example. 30 chosen lawns showed some 420 plant species; ecology and distribution of which are discussed. There exists only a weak connection between the area of the lawns and the number of species growing, whereas a very strong correlation between the richness and the area was found. At the borders of the lawns the number of species found was twice the number of species within the area. There is a clear accumulation of neophytes at the borders whereas the archeophytes are spread more or less regular. The dominating species of the class Molinio-Arrhenatheretea are seldom found in the seed bank. To estimate the influence of grazing by wild rabbits on the species inventory of the lawns feeding experiments have been carried out and the species combination of the surrounding of the rabbit’s burrows have been investigated. The reaction of the lawns to small scale disturbance was investigated by experiments too.