A Study on the Woody Plants Flora in the Ecotone of Bashang Plateau and Jibei Mountains Region,Hebei Province

The research on the woody plants flora composition of Bashang plateau and Jibei mountains region shows that there are 411 species(including infraspecific taxa) of woody plants belonging to 117 genera and 53 families in the ecotone.Among them,22 species belonging to 8 genera and 4 families of gymnosperm and 389 species belonging to 109 genera and 49 families of angiosperm are recognized respectively.In the flora,the large families and the relatively large families constitute the principal part of genera and species,while the small genera containing 2～4 species and single species genera constitute the principal part of genera.One hundred and seventeen genera of woody plants in the ecotone can be divided into 14 geographical patterns.Among them,North temperate,E.Asia N.Amer.Disjunction,Pantropic and E.Asia are important patterns.Based on the research and discussion,the major characteristics of the flora can be concluded:species are comparatively rich,the genera of temperate are dominant,the flora is ancient origin with apparently transitivity,single genus families are rich,which shows the complexity of the flora in the ecotone.