Biotic resistance to plant invasion in tropical and temperate wetlands

During the summer, we will be performing a major experiment where we want to determine the role of competition and herbivory, and the interaction between these two factors, in the establishment of invasive species.

Biological invasions are recognized as one of the main causes of biodiversity loss. Exotic species alter ecosystem structure and function and cause annual losses of billions of dollars worldwide. Freshwater ecosystems, in particular, harbor a large amount of invasive species, especially aquatic macrophytes. Submerged macrophytes play a crucial role in structuring and functioning of tropical and temperate aquatic ecosystems. However, several species have a variety of traits which make them potential aquatic weeds. The question remains, why do not all introduced species become successful in their new range?

The failure of some exotic species is often attributed to biotic resistance, which is the role of species interactions in limiting the success (i.e. establishment or performance) of introduced species. The strength of biotic resistance in freshwater environments is mainly determined by ecological interactions in two layers of the food web, competition by native vegetation and consumption by native herbivores (herbivory). Thus, our main aim in this research is to understand the variation and mechanisms underlying the success of invasion in freshwater plant communities.

Charles Elton (1958) said ‘(resistance) describes ignorance and not knowledge’ (p.117). Thus, there are plenty of questions that still need to be addressed.

Details

The internship is for a period of 4-9 months, starting in June or July. Location: NIOO-KNAW in Wageningen.

If you have any questions, please send an e-mail to one of the supervisors, Antonella Petruzzella (a.petruzzella@nioo.knaw.nl) or Liesbeth Bakker (l.bakker@nioo.knaw.nl).