Invasive C₄ plants cause greater soil greenhouse gas emissions than C₃ plants

Understanding the impact of invasive plants on the emissions of soil greenhouse gases (GHGs) is essential for developing effective strategies to mitigate invasion-induced ecosystem disruption and climate warming. Here we present a global meta-analysis of 104 studies to assess the effects of plant invasion on soil carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) emissions. Our results showed that plant invasion significantly increased all three GHG emissions from soils. Model selection analysis indicated that the photosynthetic pathway of invasive plants (C₃ or C₄) and soil organic carbon (SOC) were the primary factors governing the variation in GHGs emissions. Specifically, invasion by C₄ plants increased all three GHG emissions from soils more than C₃ plants, whereas SOC mainly influenced the invasion-induced emissions of soil CO₂ and CH₄. These findings provide mechanistic insights into how invasive plants alter soil GHG fluxes and cause the associated impacts on biogeochemical cycles.