Why is China an important centre of diversity for maple trees?

China is considered a primary centre of diversity for maple trees (Acer), a genus within the family Sapindaceae, because it hosts approximately half of all known maple species. Globally, about three-quarters of all maple species are native to Asia, with China serving as the major centre of distribution for the genus.12

The exceptional botanical diversity found in China, including its wide variety of tree species, is largely attributed to the relatively negligible impact that Pleistocene glaciations had on the region's climate. This allowed many relict forest species to survive, contributing to the country's status as a region with some of the most varied vegetation in the world. While maples are widely distributed across the North Temperate Zone, this unique environmental history has helped maintain China as a critical hub for the evolution and concentration of these trees.32