Alpine community response to Pine invasion across taxa and trophic levels

Partie de:
jeudi 19 déc. 09:00 AM (15 minutes)
Salle CD

Ecologists have long investigated the processes that regulate diversity on local scales, however, the interaction between assembly processes and biological invasions remains understudied. Understanding and predicting ecosystem response to invasion is becoming increasingly important, as the anthropogenic introduction of exotic species continues to impact and alter ecosystems around the globe. I studied the community response of alpine flora and fauna to invasion and establishment of Pinus contorta (Lodgepole Pine) into an un-forested meadow on a mountain in northern Argentine Patagonia. Specifically, I asked the question; Are invading pines filtering biotic alpine communities and does the strength of this filtering change with the age of invader? To answer this question, I measured compositional turnover in root-associated fungi and bacterial communities and plant communities between plots containing adult pines, juvenile pines (sapling) and no pines (control). I use a null model approach and generalized dissimilarity modelling to quantify the proportion of compositional turnover explained by environmental variables, specifically focusing on variables influenced by pine establishment. Finally, I investigate the directionality of community filtering, from both a phylogenetic and functional point of view to identify patterns between trophic levels and predict future community response. This study directly relates pine-induced change in environmental variables to changes in community composition across 3 major taxa (fungi, bacteria, and plants) and multiple trophic levels. The results from this study highlight the need for further research of invaded and impacted ecosystems when it comes to understanding community assembly and predicting long-term, community-wide, change.


Mon horaire

Ajouter à Mon Horaire comme Favoris