Alien invasive plants in China: risk assessment and spatial patterns

With a wide range of habitats and exploding development of international trade, China is facing escalating risk of the plant invasion. Research on the risk assessment of alien invasive plants may help us manage the invasive with priority, and is imperatively needed in China. However, until now, few studies have been conducted for the risk of alien invasive plants and its spatial patterns in China, especially with a regard to ecosystem conservation and biodiversity protection. In this paper, we assessed the risk of invasive plants and its spatial patterns. We focused on the following basic questions: Which alien invasive plants are the most noxious, and which of them are mild? How are the spatial patterns of alien invasive plants at different risk ranks? In the present study, the risk of 100 major alien invasive plants in China was assessed based on a revised risk assessment system and an extensive consult with literatures. The results indicated that there were 18 species of rank 1st, 29 of rank 2nd, 33 of rank 3rd and 20 of rank 4th. Although, there was high richness of alien invasive plants in South China, most of them were of low risk. By contrast, low richness of alien invasive plants was observed in North China and the regions in high altitude, but most of the invasive were of high risk. Compared with previous studies, our study appears to have delivered credible results and may play an early warning function, and also further our understanding of the risk of invasive plants and its spatial patterns in China, though we acknowledged that the risk assessment may have some potential weakness, and appealed timely and further investigations in future.