Ecological and evolutionary drivers of European weed invasions along a tropical to alpine environmental gradient in Hawai'i

• Antragstellerin: Dr. Gabi Jakobs
• Fachliche Zuordnung: Ökologie und Biodiversität der Pflanzen und Ökosysteme
• Förderung: Förderung von 2006 bis 2009
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 19452625

To improve our understanding of plant invasion patterns an ecosystem with strong environmental gradients may provide suitable study site. One example is Big Island, Hawai i, which is one of the few areas in the world where climatic gradients can be followed over an altitudinal range of more than 3000m, while soil conditions remain most similar over the entire range. The aim of the proposed project is to investigate the abundance and performance of introduced European weeds. A broad taxonomical and morphological variation may allow system specific generalizations and preliminary studies revealed the suitability of the study system. The main questions are; (1) Does the distribution of European weeds coincide with their distribution in the native range and does plant fitness vary across different environmental conditions? (2) What is the role of plasticity and genetic variation/adaptation in contributing to an invader s success? (3) Do the plants differ genetically from the native provenances? And if so - which mechanisms underlie these evolutionary changes? A combination of field data and common garden experiments is a promising approach to answer these questions. Since most species have first been introduced to lowland areas, we expect that ecotypes only occurring in higher altitudes are then most likely the result of post-invasion changes. To support this hypothesis of evolutionary changes towards the boundaries of the species range, we will perform genetic analysis with microsatellites. Equivalent data have already been obtained along a similar altitudinal range in the Swiss Valais.

• DFG-Verfahren: Forschungsstipendien
• Internationaler Bezug: Schweiz, USA
• Gastgeber: Professor Dr. Curtis C. Daehler