Abstract:

Background and Aims Biological invasions, one of the three most pressing environmental problems, is an important component of global change and causes considerable environmental damage and economic losses to the invaded regions. Although China is a country heavily infested with invasive alien plants, factors influencing regional spatial patterns of these species are largely unknown.
Methods In order to explore the relationship between spatial patterns of invasive alien plants and environmental and anthropological factors, this study used multiple stepwise regression and canonical correspondence analysis to determine the effects of seven environmental variables (including area, latitude, longitude, mean temperature in January, mean temperature in July, annual precipitation, frost-free days) and seven anthropological factors (including number of foreign tourists, GDP, transport density, value of imported goods, area of nature conserve, rate of nature conserve, population density) on the number, density and spatial distribution of invasive alien plants in 32 provinces of China.
Key Results It was found that the number of invasive alien plant species decreased from the south to the north, which was largely determined by the frost-free days. The density of invasive plant species declined from the southeast coast inland to the northwest, which was best explained by transport density. In addition, about 50% of the variation in invasive alien species composition across provinces was accounted for by latitude.
Conclusions Our results suggest that both natural conditions and anthropological factors play important roles in shaping the patterns of plant invasions in China. These findings may help to understand ecosystem invasibility, and predict plant invasions on a regional scale, and hence have important implications for the management of invasive species.

Key words: Frost-free days, Human impacts, Latitudinal gradient, Plant invasion, Spatial pattern, Transport density