RT Journal Article
SR Electronic
T1 Exotic species dominate due to niche overlap in a complex grassland community
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 253518
DO 10.1101/253518
A1 Lawrence H. Uricchio
A1 S. Caroline Daws
A1 Erin R. Spear
A1 Erin A. Mordecai
YR 2018
UL http://biorxiv.org/content/early/2018/01/24/253518.abstract
AB Niche differentiation can maintain biological diversity, but assessing whether it is sufficient to stabilize invaded communities – which may be far from equilibrium – remains a pressing concern. We collected experimental data and developed a dynamic model to predict competitive outcomes in a complex grassland community including both native and exotic species. We found evidence for strong competition exerted on exotic grasses, but weaker competitive impacts on California natives. Nonetheless, our model predicts that at least one exotic species will persist with high probability, while native species persist in only half of predicted outcomes. Coexistence of multiple native and exotic species is unlikely in our model. We found that fungal infection has a weak impact in this system and is unlikely to substantially affect coexistence. The results suggest that despite strong competitive impacts on exotic species, exotics are likely to out-compete some or all California native grass species in the absence of other stabilizing mechanisms. However, conservation efforts focused on the preservation of native adult bunchgrasses could substantially increase the likelihood of native species’ persistence.