How do soil micro-organisms affect the chances of woodland expansions during water pulses?

Woodland expansion in arid environments occurs episodically during wet years. Recent research indicates that tree seedling growth rate and survival is crucial to explain the differences across ecosystems and that soil microorganisms likely play a crucial role.

One of the main hypotheses to be tested is that when the first constraint has been solved for tree seed germination (water) natural soil pathogens are the next constraint preventing the establishment of the germinated tree seedlings. This has far-reaching consequences for our predictions of how climate change may affect arid ecosystems.

Such effects of soil pathogens are known from temperate forests and from tropical forests, however, they have not yet been studied in arid ecosystems. In the project, we will study the role of soil microorganisms on the germination and survival of tree species in arid ecosystems of Chile and Peru and will be developed in close collaboration with colleagues at Wageningen University (Dr. Milena Holmgren: Milena.holmgren@wur.nl).

Duration
6 Months.

More information
Wim van der Putten, e-mail: w.vanderputten@nioo.knaw.nl