Traditional attempts of floristic studies typically focus on the analyses of taxonomic composition and areal-types of flora, often ignoring the rich context that evolutionary history can provide. In this study, based on the recent study examining the delineation of floristic regions in Yunnan, by combining data on the distributions and phylogenetic relationships of 1,983 genera of native seed plants, we explore how taxonomic composition, phylogenetic relatedness, and phylogenetic structure vary across the different geographic regions in this area. As predicted, phylogenetic diversity was well correlated with taxonomic diversity among the geographic regions. Using null model analyses, we found evidence of nonrandom phylogenetic structure across the region. Also, phylogenetic relatedness was well correlated with taxonomic composition between geographic regions in Yunnan. Cluster analyses of the similarities of phylogenetic relatedness and taxonomic composition show that geographic regions with tropical floristic affinity form a single cluster separate from another cluster composed of geographic regions with temperate floristic affinity. Our results show that the integration of phylogenetic information can help us to better understand the characteristics and origin of flora.
Received: 03 January 2016
Published: 06 March 2017