Invasions of alien plants pose unprecedented challenges to China's nature reserves under climate change

Biological invasions are considered the second-greatest threat to global biodiversity. In China, nature reserves (NRs) are crucial in terms of biodiversity conservation, but many are at high risk of biological invasion. However, as climate change progresses the NR invasion risk posed by invasive alien plants (IAPs) remains unclear. Here, we compiled an inventory of 402 IAPs with over 120,000 occurrences to investigate IAP distribution patterns and the potential invasion risks in China’s NRs under current and future climate scenarios. We also analyzed the key environmental and socioeconomic factors influencing IAP distribution. Our results indicate that approximately 63% of national nature reserves (NNRs) and 38% of provincial nature reserves (PNRs) contain IAPs. Most NRs with high numbers of IAPs are located in South, East, Southwest, and Central China. In addition, up to 73% of PNRs and 80% of NNRs are highly vulnerable, which have IAP records within NRs or outer 5 km buffer areas. Under current and future climate scenarios, approximately 85% of China’s NRs contain suitable habitats for IAPs, representing a 38% increase compared to the collected distribution. The predicted IAP distribution pattern generally shows a decreasing trend from southeast to northwest. Population density, elevation, area, year of establishment, and temperature annual range (BIO7) significantly affect IAP richness in NRs. Under future climate scenarios, China’s NRs will be confronted with a greater risk of IAP invasion. Our findings can work as fundamental material when managing IAPs in NRs, providing valuable insights for targeted strategies and improving the protective effectiveness of NRs in China.