Abstract:
:The taxonomic richness of seed plants at different taxonomic levels was compared between temperate East Asia and North America at both continental and semi-continental scales. In each comparison, land area and latitude range were adjusted to a comparable level between the two continental regions. East Asia is significantly more diverse than North America. In general, differences in taxonomic diversity arise at and below the genus level. At the continental scale, East Asia has 1.3 and 1.5 times as many genera and species, respectively, as North America. The northern part of East Asia has 1.1 times as many species as the northern part of North America. At the genus level, the northern part of East Asia is less diverse than the northern part of North America by a factor of 0.94. This pattern indicates that the diversity bias between the two continental regions results from the flora of southern East Asia. The diversity differences between East Asia and North America are not homogenously distributed across different plant groups. At the species level, East Asia had significantly more species than expected in magnoliids, alismatids, Liliidae, ranunculids, and rosids and had significantly less species in the Commelinidae, Caryophyllidae, and euasterids than North America.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Qian Hdoi
10.3732/ajb.89.11.1818subject
Has Abstractpub_date
2002-11-01 00:00:00pages
1818-25issue
11eissn
0002-9122issn
1537-2197pii
89/11/1818journal_volume
89pub_type
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