Invasion impacts in terrestrial ecosystems: Global patterns and predictors
Madhav P. Thakur, Zhizhuang Gu, Mark van Kleunen, Xuhui Zhou
Abstract
Biological invasions can alter ecosystems, yet their impacts vary across ecological contexts. Using a global meta-analysis of 775 studies (2223 effect sizes) in terrestrial systems, we show that the most consistent negative impacts are reductions in native plant diversity caused by invasive plants and increases in greenhouse gas emissions driven by both invasive plants and animals. However, evidence of publication bias suggests the latter should be interpreted with caution. Invader residence time emerged as a key predictor: Longer residence times intensified the negative effects of invasive plants on native diversity, whereas impacts on soil abiotic properties tended to weaken over time. Our synthesis reveals that some properties, such as native plant diversity, remain persistently sensitive to invasion, whereas others are more variable as invasions persist.