Mitigation of Legacy Effects in Invaded Soil via Alien Plant‐Derived Biochar

ABSTRACT The introduction of nonnative plant species often leads to extensive land colonization and poses a threat to already limited arable land resources. Restoring invaded land and improving soil fertility are therefore essential. In this study, both biochar derived from the invasive Chromolaena odorata and a fungicide were used to improve the soil invaded by this species. The results revealed that fungicide application increased the total biomass of the subsequent plants growing in the invaded soil and significantly altered the recruitment of mycorrhizal and saprophytic fungi. The addition of biochar to invaded soil had a negative legacy effect on subsequent invasive plants but a positive effect on native plants. The combined application of biochar and fungicide effectively diminished the competitive advantage of invasive species, whereas biochar alone markedly increased the competitiveness of native plants. This study proposes a remediation method for mitigating the legacy effects of alien plant invasion that not only suppresses the spread of invasive species but also improves soil fertility and provides potential economic benefits.