The roles of climatic factors in spatial patterns of alien invasive plants from America into China

The roles of climatic factors in plant invasions have drawn intense attention in the past. America was one of the major donors of the invasive plants in China. In this study, we investigated the roles of climatic factors in plant invasions from America into China through Akaike's information criterion model analysis in terms of specific geographical origins, respectively. From south to north, decreasing trends of species diversity were observed on the plants from Central-South America and Mexico, while the greatest alien species diversity in mid-Chinese latitudes was observed on the invaders from North America; For the invaders from Central-South America and Mexico, climatic factors explained most of the spatial variations, while for those from North America, the roles of the climatic factors were weak. The role of the climatic factors in plant invasions may, in some extent, depend on the ecological characters inherited form the geographical origins and their accommodation to the climate of the invaded regions. If the invasive plants were introduced into the region with similar environment to their area of origin, the role of the climatic factors may be shadowed by other factors. However, for the invaders whom were introduced into the regions vastly different from their areas of origin, climatic barriers may be responsible for most of the spatial variations. The invasive plants from Central-South America and Mexico may have strong potential to invade regions at higher latitude in China in the scenario of global warming, while for the invaders from North America, the impacts of global warming may be shadowed by other factors.