Studies on flora diversity of the seed plants in Laoxiancheng Nature Reserve,Zhouzhi,Shaanxi

The flora diversity of the seed plants in Laoxiancheng Nature Reserve,Shaanxi,Zhouzhi was explored.The major results of the flora are as follows:Species are comparatively rich;there are 1 131 species(including infraspecific taxon) of seed plants belonging to 109 families and 453 genera in northwest china.Among them,there are 13 species belonging to 9 genera,4 families in gymnosperm.1 118 species belong to 444 genera and 105 families in angiosperm.In those plants,the big families and the big genera play important roles;the geographical elements of the flora are comparatively complex,and the genera of temperate are the dominant areal types,the flora is ancient in origin.The flora has widely relate to other area,and the flora is the crisscrossing and assembling,mixing and transition of diversified floristic elements.These analysis results showed that this region is an important composition of Qinling Mountain plant flora.