Characteristics of the Seed Plants Flora in Qinling Mountains and Its Relationship with Floras in Other Mountains

Based on field investigation and references,we analyzed the floristic characteristics of seed plant in Qinling Mt.,and the relationship between the folra of Qinling Mt.and 7floras.The results showed that:(1)There are 3 839 species belonging to 164 families and 1 052 genera in Qinling Mt..(2)The geographical elements of the flora are comparatively complex,and the genera of temperate are the dominant areal types(618genera,account for 58.75),but there was a transition from subtropical to temperate types.Thus,the research area is an important intersection region.(3)There were many ancient and relict spermatophyte species in Qinling Mt.,which represented a large proportion of endemic Chinese species and those with a nationally conserved status.Tertiary relict plant species are rich in abundance and they form an important part of plant communities in Qingling Mt.,which indicates that the origin of the flora is very ancient.(4)The flora of Qinling Mt.is very closed to Dabieshan Mt.,Bashan Mt.and Hengduanshan Mt.,and less close to Sejishan Mt..It is far from the north Qilianshan Mt.and Helanshan Mt..This shows that the Qinling Mt.range is the acknowledged north-south climatic boundary.