【摘要】 外来入侵植物区系的研究对外来入侵植物的防控具有重要理论意义和现实意义。利用大尺度的外来入侵植物分布数据和区系信息,采用聚类分析和多因子排序的方法探讨影响中国外来入侵植物区系成分构成空间分异格局的主要因子。结果表明,中国外来入侵植物区系总体构成以热带区系成分为主,其次为温带区系成分和世界分布成分。按照各研究单元内外来入侵植物的区系组成,聚类分析将研究区域划分为三个地区,即低纬度的南部地区,中纬度的中部地区和高纬度、高海拔地区。其中,低纬度南部地区的外来入侵植物区系组成以热带区系为主,而高纬度、高海拔地区的区系构成以温带区系成分为主。基于地理因子的多因子排序表明,在纬度梯度上区系成分的空间分异最为明显,其次为海拔梯度和经度梯度;基于气候因子的多因子排序表明,影响区系成分空间分异最强烈的气候因子为1月均温,其次为无霜期和年降水量。更多还原

【Abstract】 Research on floristic elements of invasive alien plants is of great significance.In this paper,cluster analysis and multi-factor ordination are conducted on the flora of invasive alien plants,based on flora information,geographical and climatic factors in large scale.The results show that tropical elements take the largest proportion,temperate ones ranking the second.Cluster analysis shows that the study area can be divided into 3 regions.They are the southern region in low latitude,central region in middle latitude and the region in high latitude or altitude.In the southern region in low latitude,tropical elements gain the dominance,while in the region in high latitude or altitude,the majority of them are temperate ones.The multi-factor ordination,based on geographical factors indicates that the most significant variation is mostly impacted by the latitudinal gradient,altitude ranking next to it.The multi-factor ordination based on climatic factors implicate that mean temperature in January plays the most important role in shaping the spatial patterns of floristic elements,frost-free days and mean annual precipitation ranking the second.更多还原