Neophytes in Austria: habitat preferences and ecological effects
Most of the 1110 neophytic vascular plant species recorded for Austria occur in ruderal and segetal vegetation. However, some natural and semi-natural vegetation types are also strongly invaded by neophytes. These include riparian areas, and floodplain forests. In contrast, the invasion success of neophytes in alpine meadows and dwarf shrub communities, in bogs, fens and moist meadows, as well as in rocks and screes is very low. The invasion success of neophytes seems to be associated with a strong anthropogenic and natural disturbance regime, excessive supply of nutrients and warm climate. The number of neophytes which threaten biodiversity is low: 17 species are classified as invasive and another 18 species as potentially invasive.
These species are: Acer negundo, Ailanthus altissima (EPPO list of invasive alien plants), Ambrosia artemisiifolia (EPPO list), Amorpha fruticosa, Asclepias syriaca, Aster lanceolatus, Aster novi-belgii, Bidens frondosa (EPPO list), Buddleja davidii, Duchesnea indica, Eleagnus angustifolia, Elodea canadensis, Elodea nuttallii (EPPO list), Epilobium ciliatum, Fallopia japonica (EPPO list), Fallopia x bohemica (EPPO list), Fallopia sacchalinensis (EPPO list), Fraxinus pennsylvanica, Glyceria striata, Helianthus tuberosus (EPPO list), Heracleum mantegazzianum (EPPO list), Impatiens glandulifera (EPPO list), Impatiens parviflora, Lupinus polyphyllus (EPPO list), Mahonia aquifolium, Pinus strobus, Populus x canadensis, Prunus serotina (EPPO list), Pseudotsuga menziesii, Robinia pseudacacia, Rudbeckia laciniata, Senecio inaequidens (EPPO list), Solidago canadensis (EPPO list), Solidago gigantea (EPPO list), Syringa vulgaris. This list was adopted by the Austrian Action Plan on Invasive Alien Species (see link below).
Although invasive neophytes compose only a small fraction of the complete flora (0.9%) in Austria, they probably exert a significant influence on natural and semi-natural ecosystems. Ecological effects caused by invasive neophytes in Austria include changes in species composition, succession patterns, nutrient cycles via eutrophication and in evolutionary paths via hybridization.
Sources
Walter J, Essl F, Englisch T, Kiehn M (2005) Neophytes in Austria: Habitat preferences and ecological effects. Biological Invasions 5, 13-25.
Austrian Action Plan on Invasive Alien Species: http://www.umweltbundesamt.at/en/umweltschutz/naturschutz/natur_aktuell/aktionsplan_neobiota/