Species, Distribution And It’s Limiting Factors Of Invasive Alien Plants In Beijing

In order to explore the spreading and distribution of the invasive plants in Beijing, and to study the driving factors impacting the distribution of the invasive plants, investigations were conducted in twelve districts and counties in Beijing. The distribution pattern of invasive species and variation along the altitude gradients of invasive species were analyzed, and the correlation between the invasive species and impacting factors were carried out. The results showed there were47species of invasive plant species in Beijing.The number of species vary in different areas in Beijing, but Tongzhou, Mentougou, huairo and miyun have great number of invasive species, also the invasive plants concentrate apparently in three dispersal centers. The invasive plants distribute in different altitudes, but mainly distribute at100m-900m,and the pattern of the number of invasive species decreased along with the increase of the altitude fit the linear function.The correlation analysis of the number of the invasive plant species and some possible limiting factors revealed the number of the invasive alien species are negatively related to the amounts of imports and first-class highway density, while positively related to the vegetation coverage rates. These phenomena might be explained by the potential influence of the origin of the forests and landscape fragmentation which caused by human activities diversity and its uncertainty in Beijing. The diverse disturbance supply the more habitat for more plants, and the distribution pattern of invasive species and the various human activities might increase the difficulty in preventing and controlling the invasive plants.