云南地区种子植物属多样性的纬度格局与区系起源的关系

利用大尺度的种子植物物种分布信息,探讨了云南地区种子植物属多样性的纬度分布格局与区系起源的关系.结果表明:起源于热带地区的种子植物属多样性与纬度梯度呈负相关关系,这在一定程度上暗示着该植物类群存在着北上扩散的趋势;起源于温带地区的植物属多样性与纬度梯度呈正相关关系,暗示着其南下扩散的趋势.热带区系属的多样性纬度格局可能在一定程度上造成了总体属多样性在纬度梯度上递减.Rapoport法则可能更适用于起源于热带地区物种多样性格局的解释.

Latitudinal Patterns of Genus Diversity of Seed Plants in Yunnan with a Regard to Their Floristic Origins

On the basis of distribution information at large-scale,the latitudinal patterns of genus diversity of seed plants in Yunnan with a regard to their floristic origins were examined. The results showed that tropical genus diversity was negatively correlated with latitudinal gradient,suggesting a south-to-north spreading trend; however,temperate genus diversity showed positive correlation with latitudinal gradient,implying a north-to-south spreading trend. The total genus diversity and diversity of tropical genera shared the similar decreasing latitudinal patterns. It is suggested that Rapoport's rule may be more applicable to explain the latitudinal patterns of species diversity originated from tropical regions. It is also suggested that the hypothesis of floristic origins is probably one of the effective theories to explain latitudinal patterns of taxa diversity.