Do invasive alien plants benefit more from global environmental change than native plants?

Liu, Y., Oduor, A. M., Zhang, Z., Manea, A., Tooth, I. M., Leishman, M. R., ... & Kleunen, M. (2017). Do invasive alien plants benefit more from global environmental change than native plants?. Global change biology, 23(8), 3363-3370. PDF.

Summary

Invasive plants reduce biodiversity, disrupt ecosystems, and cause considerable economic losses. Previous studies have predicted that global change factors will further enhance plant invasions. However, evidence of this interaction needs to be synthesized to test these predictions. Liu et al. (2010) conducted a meta-analysis of studies that compared the effects of global changes (increased CO2, increased temperature, increased nitrogen deposition, increased precipitation, and decreased precipitation) on the relative performance of invasive vs. native plants.  A meta-analysis combines all available comparative studies to assess general trends across the invasion ecology literature. Overall, the authors found that invasive plants responded significantly more positively than native plants to every global change except change in precipitation (where there were fewer studies and no significant effect). Therefore, this study provides compelling evidence that increased CO2, warming, and N deposition will promote plant invasions in the future. 

Take home points

  • Invasive plants respond more positively than native plants to global changes that increase resources (increased CO2, N deposition, and increased temperature, which lengthens the growing season).

  • Global change will likely increase the competitiveness of invasive plants.

Management implications

  • Fast growing, ‘weedy’ species that require a lot of resources are likely to do better with higher CO2 and nitrogen. Invasive plants that exhibit weedy traits should be higher priority on watch lists or management plans.

  • Invasive plants that grow in the early spring or persist into the late fall may have an advantage with warmer temperatures.  Early-season invasive plants should also be a management priority.

Keywords

Shifting Seasons; Competitiveness; Meta-analysis; Invasive Plant; Terrestrial Habitat; Risk Assessment