Der Regenerationsnische von Bäumen an der alpine Baumgrenze: positive und negative Vegetationseinflüsse während der Samenkeimung und der Etablierung von Sämlingen

• Antragstellerin: Professorin Dr. Maaike Bader
• Fachliche Zuordnung: Ökologie und Biodiversität der Pflanzen und Ökosysteme
• Förderung: Förderung von 2010 bis 2018
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 181496145

The potential altitudinal limit for tree growth is probably set by a lack of warmth during the growing season. However, the altitudinal limit for tree establishment is probably set by quite different climatic factors, such as freezing temperatures and interacting stressors such as excess solar radiation. This may explain why few alpine treelines currently reach the potential tree-growth limit. Establishment limitations also have important bearings for treeline responses to climatic changes. Nearly all ecophysiological treeline research currently focuses on growth limitations for adult trees. We will, however, focus on the earliest life stages, germination and seedling performance, which represent strong demographic bottlenecks determining treeline dynamics and positions. We aim to clarify the relative importance and the interactions of growing season warmth, growing season length, and frost and radiation stress for the initial establishment of treeline-forming tree species in the alpine life zone. By focussing on seedlings, by explicitly integrating and ranking multiple causes and by addressing functional diversity among tree species, this project will be an important step to overcome many of the current controversies concerning treeline dynamics.

• DFG-Verfahren: Sachbeihilfen
• Beteiligte Person: Professor Dr. Gerhard Zotz