Filtern
Erscheinungsjahr
- 2013 (2) (entfernen)
Dokumenttyp
Sprache
- Englisch (2) (entfernen)
Volltext vorhanden
- ja (2)
Gehört zur Bibliographie
- nein (2)
Schlagworte
- Sisymbrion (1)
- apomict distribution (1)
- apomict traits (1)
- apomixis (1)
- ecological traits (1)
- environmental conditions (1)
- invasive species (1)
- neophyte (1)
- syntaxa (1)
- transformer (1)
Summed frequency data of apomictic taxa derived from vegetation relevées from Central Europe were correlated with ecological traits – water content of soil, calcium and magnesium content of soil or water, nutrient content of soil or water, environmental dynamics, hemeroby, frequency of stress-tolerant species, salt tolerance, altitude, height, and frequency of annual taxa – of alliances of the Central European vegetation. The partly problematic identification of taxa where apomixis is important for seed production was based on a literature review. In Central Europe, high altitudes favour apomictic taxa. Otherwise, no correlations between ecological factors attributed to the alliances of the European phytosociological system and frequencies of apomictic taxa in the alliances of the European phytosociological system were found. Analyses could not confirm theories on ecological preferences of apomictic taxa; e.g., that competition penalizes apomicts, apomicts have better colonizing abilities than sexual plants, or apomicts have larger ranges than their sexual relatives could not be confirmed.
Only a small proportion of introduced plant species become invasive and may eventually create ecological or economic problems. In many species it is still not clear which traits cause biological inva-sions. As a case study we focussed on the fast-spreading Epilobium brachycarpum in Central Europe to investigate the potential of this species to become a transformer or agricultural weed. We (1) documented the spread of the species in Central Europe, (2) modelled its range and (3) seed dispersal, (4) described its phytosociological alignment, (5) analysed the traits of invaded vegetation types, (6) described seed production, population densities and life cycle, (7) did competition and germination tests, and (8) drafted a risk assessment. Relevant traits and characteristics of E. brachycarpum are (i) formation of dense stands under ruderal conditions, (ii) high seed production, (iii) effective seed dispersal, (iv) high competitiveness on bare soils against other ruderal plants, and (v) ecological niche shift com-pared to its native range. We expect E. brachycarpum to settle in the Mediterranean, sub-Mediterranean and many parts of temperate Europe within the next decades in habitats strongly altered by human activities, especially open stands of the alliance Sisymbrion. We predict that E. brachycarpum will become a noxious weed in vineyards, and that it will also colonise vegetation of the alliances Bidention and Carici-Epilobion.