Positive Interactions of Native Species Melt Invasional Meltdown over
Long-Term Plant Succession
Abstract
Positive interactions have been hypothesized to influence plant
community dynamics and species invasions. However, their prevalence and
importance relative to negative interactions remain unclear, but are
fundamentally important for both theoretical and applied ecology. We
examined pairwise biotic interactions using over 50 years of
successional data to assess the prevalence of positive interactions and
their effects on each focal species (either native or exotic). We found
that positive interactions were widespread and the relative frequency of
positive and negative interactions varied with establishment stage and
between native and exotic species. Specifically, positive interactions
were more frequent during early establishment and less frequent at later
stages. Positive interactions involving native species were more
frequent and stronger than those between exotic species, reducing the
impact of invasional meltdown on succession. Our study highlights the
role of positive native interactions in shielding communities from
biological invasion and enhancing the potential for long-term
resilience.