Study on Flora Diversity of Seed Plants in the Forest of Tianmu Mountains,Henan Province

Tianmu Mountains lie in the southwest of Henan between 33°31′-32°38′ N latitude and 113°45′-113°55′E,In Henan,there are 1824 species of seed plants,belonging to 707 genera and 155 families in Tianmu Mountains.The areal types of the genera and the species are abundant.Based on their geographical distribution,707 genera are classified into 15 areal types with most belonging to the temperate distribution pattern plant(64.49%) and many belong to tropical one(31.53%) and 1824 species are classified into 15 areal types.Analysis of the floristic elements based on genera and species shows that the temperate floristic elements are predominant in Tianmu Mountains.It is highest percentage of temperate distribution elements of genera and East Asia distribution elements of species show that this area has obvious temperate characteristics of the flora.The seed plant in the area is age-old in origin,which contains 20 rare and threatened species,25 endemic genera and 40 monotypic genera.The flora of Tianmu Mountains is of typical tertiary flora system.