Species Diversity Distribution Patterns of Chinese Endemic Seed Plants Based on Geographical Regions

Abstract

Based on a great number of literatures, we established the database about the Chinese endemic seed plants and analyzed the compositions, growth form, distribution and angiosperm original families of them within three big natural areas and seven natural regions. The results indicate that the above characters of Chinese endemic plants take on relative rule at the different geographical scales. Among the three big natural areas, Eastern Monsoon area has the highest endemic plants richness, whereas Northwest Dryness area is the lowest. For life forms, herbs dominate. In contrast, the proportion of herbs of Eastern Monsoon area is remarkable under other two areas. Correspondingly the proportions of trees and shrubs are substantially higher than other two. For angiosperm original families, the number is the highest in Eastern Monsoon area, and lowest in Northwest Dryness area. On the other hand, among the seven natural regions, the humid and subtropical zone in Central and Southern China has the highest endemic plants richness, whereas the humid, hemi-humid region and temperate zone in Northeast China has the lowest. For life forms, the proportion of herbs tends to decrease from humid, hemi-humid region and temperate zone in Northeast China to humid and tropical zone in Southern China. Comparably, trees, shrubs and vines or lianas increase with the same directions. This fully represents these characters of Chinese endemic plants vary with latitudinal gradients. Furthermore, as to the number of endemic plants belonging to angiosperm original families, the number is the most in humid and subtropical zone in Center and Southern China, and tropical zone in Southern China in the next place. In contrast, the endemic plant of these two regions relatively is richer than that of The Qinghai-Tibet alpine and cold region. All above results sufficiently reflect that the Chinese endemic plants mainly distribute in Eastern Monsoon area, especially humid and subtropical zone in Center and Southern China and tropical zone in Southern China. Furthermore, the flora of Eastern Monsoon area, in particular humid and subtropical zone in Center and Southern China and tropical zone in Southern China, is more ancient and original than that of Northwest Dryness area and Qinghai-Tibet alpine and cold area.

Diversity and distribution of parasitic angiosperms in China

“…From east to west, Chinese topography is characterized by terrain, ranging from plains in the eastern provinces (>500 m at altitude) to basins in the middle ones (1,000–2,000 m at altitude), to the Qinghai‐Tibet Plateau in the west provinces (above 4,000 m at altitude; ECCPG, ). Such a climate and geographic diversity may result in a wide range of habitats and facilitate local species differentiation, giving rise to endemism (Huang, Ma, & Huang, ; Wen et al., ). For example, the high species richness of the genus Pedicularis (including 441 herbaceous species and 89 subspecies or variants) in China (Wu et al., 1994–2012) has been frequently attributed to the extremely high topographic heterogeneity, mainly resulting from the uplift of the Tibetan Plateau, in the southwest mountainous areas (Zhao et al., ).…”

“…(1,000-2,000 m at altitude), to the Qinghai-Tibet Plateau in the west provinces (above 4,000 m at altitude; ECCPG, 1985b). Such a climate and geographic diversity may result in a wide range of habitats and facilitate local species differentiation, giving rise to endemism (Huang, Ma, & Huang, 2017;Wen et al, 2016). For example, the high species richness of the genus Pedicularis (including 441 herbaceous species F I G U R E 1 Distribution of species richness (a) and area-corrected species richness (b) of parasitic plants in 28 provinces of China and 89 subspecies or variants) in China (Wu et al, 1994(Wu et al, -2012 has been frequently attributed to the extremely high topographic heterogeneity, mainly resulting from the uplift of the Tibetan Plateau, in the southwest mountainous areas .…”

Conifers in Mountains of China

“…There are totally eight conifer genera endemic to China, and seven of which are monotypic genera except Cunninghamia [11]. Pinaceae contains three endemic genera, Cathaya, Nothotsuga and Pseudolarix.…”

“…The complexity and diversity of regional climate and landform could affect directly or indirectly the speciation, differentiation, migration of Chinese endemic conifers [12]. Known for highly topographic heterogeneity, southwestern China is the hotspot of endemic conifers [11,13]. The general distribution of endemic genera of conifers in China is as follows:…”

“…Fourteen typical conifer associations from five vegetation types were selected to specify conifer spatial distribution limits. Associations 1-4 are from cold-temperate and temperate mountain conifer forests, association 5 from temperate conifer forests, associations 6-9 from subtropical conifer forests, association 10 from tropical conifer forests, and the other four (11)(12)(13)(14) from subtropical and tropical mountain conifer forests [10,17].…”