Non-native plants have greater impacts because of differing per-capita effects and nonlinear abundance-impact curves.
Invasive, non-native species can have tremendous impacts on biotic communities, where they reduce the abundance and diversity of local species. However, it remains unclear whether impacts of non-native species arise from their high abundance or whether each non-native individual has a disproportionate impact - that is, a higher per-capita effect - on co-occurring species compared to impacts by native species. Using a long-term study of wetlands, we asked how temporal variation in dominant native and non-native plants impacted the abundance and richness of other plants in the recipient community. Non-native plants reached higher abundances than natives and had greater per-capita effects. The abundance-impact relationship between plant abundance and richness was nonlinear. Compared with increasing native abundance, increasing non-native abundance was associated with steeper declines in richness because of greater per-capita effects and nonlinearities in the abundance-impact relationship. Our study supports eco-evolutionary novelty of non-natives as a driver of their outsized impacts on communities.
['Pearse|Ian S|IS|https://orcid.org/0000-0001-7098-0495', 'Sofaer|Helen R|HR|https://orcid.org/0000-0002-9450-5223', 'Zaya|David N|DN|', 'Spyreas|Greg|G|']
D005075:Biological Evolution D058865:Introduced Species D010944:Plants D053833:Wetlands
per-capita effects Abundance-Impact Curves wetlands eco-evolutionary novelty community assembly invasive species impacts longitudinal analysis