Data from: Examining differences in phylogenetic composition enhances understanding of the phylogenetic structure of the shrub community in the northeastern Qinghai-Tibetan Plateau

Abstract: Periodic climatic oscillations and species dispersal during the
post-glacial period are two important causes of plant assemblage and
distribution on the Qinghai-Tibet Plateau (QTP). To improve our
understanding of the bio-geological histories of shrub communities on the
QTP, we tested two hypotheses. First, the intensity of climatic
oscillations played a filtering role during community structuring. Second,
species dispersal during the post-glacial period contributed to the
recovery of species and phylogenetic diversity and the emergence of
phylogenetic overdispersion. To test these hypotheses, we investigated and
compared the shrub communities in the alpine and desert habitats of the
northeastern QTP. Notably, we observed higher levels of species and
phylogenetic diversity in the alpine habitat than in the desert habitat,
leading to phylogenetic overdispersion in the alpine shrub communities
versus phylogenetic clustering in the desert shrub communities. This
phylogenetic overdispersion increased with greater climate anomalies.
These results suggest that 1) although climate anomalies strongly affect
shrub communities, these phenomena do not act as a filter for shrub
community structuring, and 2) species dispersal increases phylogenetic
diversity and overdispersion in a community. Moreover, our investigation
of the phylogenetic community composition revealed a larger number of
plant clades in the alpine shrub communities than in the desert shrub
communities, which provided insights into plant clade-level differences in
the phylogenetic structures of alpine and desert shrub communities in the
northeastern QTP.