Verbreitung, Abundanz und Standorte ausgewählter Neophyten in der Stadt Basel (Schweiz)

Abstract

The abundance and distribution of twelve neophytes were studied in the city of Basel, Switzerland. The selected species are Ailanthus altissima, Buddleja davidii, Conyza canadensis, Erigeron annuus s.l., Heracleum mantegazzianum, Impatiens glandulifera, Impatiens parviflora, Matricaria discoidea, Reynoutria japonica, Robinia pseudoacacia, Solidago canadensis, and Solidago gigantea. All sites with spontaneous and subspontaneous occurrences were recorded and assigned to 124 grid squares of 500 m × 500 m. At each site, abundance and selected habitat factors were scored. Common species of wide distribution and high abundance were Conyza canadensis and Solidago canadensis, while Heracleum mantegazzianum, Impatiens glandulifera and Reynoutria japonica occurred at rather few sites and low abundance. The specific quality of the urban habitat of each species and its particular distribution type were analyzed for each species. The aim of this study was to provide basic information on the spatial and temporal biomonitoring of neophytes in Basel and will be continued.