Spatial patterns and hotspots of plant invasion in China

Abstract

Understanding the large-scale distribution patterns of invasive alien plants can not only identify potential high-risk areas but also provide key information for developing management strategies to mitigate plant invasion. Here, for the first time, we mapped the spatial distribution of 239 invasive plant species in China at much finer spatial resolution (50 × 50 km2). We also developed a new metric, invasion level score (ILS), which represent both invasive plant richness and the number of high-risk invasive plants per grid cell, to identify hotspots of plant invasion. Finally, we compared differences in invasive plant richness and ILS between protected and non-protected areas. We found that the counties and grids in the southern and eastern coastal regions of China have the highest species richness and ILS. The richness and ILS decrease from southeast to northwest China. Meanwhile, the high-risk areas for invasion level are concentrated in and around provincial capitals in the southern, eastern, and northern China. We also found that protected areas in China have significantly more invasive plants and higher ILS than non-protected areas. The grid cells with high invasive plant richness and ILS are mostly distributed in regions with high population density, likely due to urban effect. The need to direct management attention towards the southern and eastern China and particularly within protected areas was suggested by our findings. Our study provides a comprehensive assessment of the distribution and risk of invasive plants in China, as well as a scientific foundation for further advancing the prevention and management of invasive plants.