Temporal dynamic of plant-soil feedback during biological invasion depended on soil environmental context

Abstract

Aims Plant-soil feedback (PSF), which may vary across space and time, is considered an important mechanism in biological invasion. However, it is still unclear how PSF change during biological invasion in heterogeneous environmental background.Methods Here, we measured the effects of soil microbial communities on the invasive species Ageratina adenophora and soil fungal communities at 24 sites with different invasion periods in two forest gaps with contrasting soil environmental backgrounds. The dominance of A. adenophora (cover and aboveground biomass) and diversity of native species at these sites were evaluated.Results In the lightly disturbed forest gaps, A. adenophora showed strong a positive response to their soil biota relative to sterilized soil (total PSFs), but a negative response to their own soil biota relative to other species’ soil biota (specific PSFs), which increased over their residence time. However, in the severely disturbed forest gaps, the invader had strong positive specific PSFs, which were maintained over a long invasion history. Higher resistance against soil pathogens may contribute to long-term maintenance of positive specific PSFs. Correspondingly, the diversity, richness of native species and dominance of A. adenophora did not significantly change during biological invasion in the lightly disturbed gap whereas in the severely disturbed gap, native species declined, and A. adenophora dominance increased after a long invasion.Conclusions These findings indicate that changes in PSFs may contribute to changes in the dominance and impact of invasive species in forest, and also highlight the need to consider the habitat context when studying PSFs.