Aussaat

Aussaat 2

Plot 2

Germination and survival of species along an elevation gradient (PhD 2016-2019)

A field experiment along an elevation gradient (2000 m, 2300 m, 2600 m, 2900 m a.s.l.) in the Central Austrian Alps (Obergurgl) will test the effects of altitude, soil type, presence of established species, provenance of seeds, and propagule type on germination and survival of species. Three species groups will be sown: ubiquitous species, species moving to higher altitudes, species disappearing at higher altitudes due to climate warming. Herbs, grasses and cushion plants are included. Two propagule types, i.e. seeds vs. bulbils, will be compared. The collection sites were at 2300 m (subalpine zone) and at > 2600 m a.s.l. (alpine zone), respectively.

Hypotheses

Hypothesis 1: In a changing climate, species able to adapt quickly will have major advantages compared to species, which are locally adapted. Species from high altitudes might be highly adapted to their actual site conditions: i.e., maternal effects or local adaptation may interfere adaptation to new conditions. Such species could be the losers of climate change. In contrast, ubiquitous species or species from lower altitudes probably have a higher adaptive ability and they should be able to migrate to higher altitudes in the course of climate warming.

Hypothesis 2: The higher the elevation, the higher the facilitation effects of already established species on the performance of invading species. To test this, seedling emergence and establishment will be investigated close to established plants and on cleared sites (aboveground vegetation removed).

Hypothesis 3: Aboveground and belowground competition affects seedling emergence and survival. Seed are sown on artificial soil and seedling recruitment will be compared to sites with missing aboveground vegetation and to sites with established plants.

Hypothesis 4: Species with clonal reproduction should perform better than species with recruitment by seeds. Species propagating by bulbils will be sown and the establishment will be compared with that of seeds.


Funding
David and Claudia Harding Foundation, Royal Botanic Gardens, Kew (UK)

Personnel involved
Vera Margreiter (PhD)
Brigitta Erschbamer