Study On The Woody Plants Flora In The Transition Zone Of Bashang Plateau And Jibei Mountanious Region In Hebei

Investigations were given to the flora of woody plants and vegetation in the transitionzone of Bashang plateau and Jibei mountanious region from 2001-2005, while woody plantswere collected and identified. These conclusions are drawn from the comprehensiveinvestigation and analysis about the flora. There are 321 species (including infraspecific taxa)of the wild woody plants in the transition zone, which belonging to 47 families and 105genera. The flora includes 11 species of Gymnosperm belonging to 7 genera and 3 familiesand 310 species of Angiosperm belonging to 98 genera and 44 families (they are alldicotyledons). 7 dominant families consist of 40 genera and 163 species, with over 10 speciesin each one, and these figures represent about 14.9%, 38.1% and 50.9% of the correspondingstatistics for the local wild woody plants. 6 dominant genera with over 10 species in each onetake 5.7% of the total local genera and 27.2% of the total species. Only 1 monogenus(Ephedraceae) belongs to the transition zone. Local monogenus families are abundant, in all19 ones, which share about 40.4% of the regional total families. That reflects the complexityof the flora. 52 monotypic genera take up 49.5% of the local total genera. This is the archaictrait of the regional flora's origin.On the base of the opinion of Professor Wu Zheng-Yi (1991, 2003) about the areal-type of China seed plants, the 105 genera in the region can be divided into 13 types. 42 genera including 182 species belong to North temperate, sharing 40% of regional total genera. This type takes the first position in the 13 types. There are 17 genera belonging to the tropical elements in the area. This appears to reflect distinctive temperate trait of the woody flora.According to the ordination of R/T (tropic genera / temperate genera), the ratio of R/T takes on a descendant trend, as the increasing of latitude to the data of 8 areas and an apparent rule on latitude zonation of floristic variation is expressed.The similar result was obtained through the calculation of shared genera and generic similarity index between these 9 floras. The results show that the transition zone is closest (70.8%) to the Xiaowutaishan Nature Reserve but farthest (36.2%) to Liankangshan Nature Reserve.According to the approach of the division of life form in China Vegetation, the style ofwild woody plants in the region can be divided into arbor, shrub and liane. There are 198 species of shrub in the flora, which shares about 62% of the total species. The number is prominent. There are only 8 liane, which is the least in the flora.Based on the opinion of China Vegetation, the woody plants communitis of the transition zone can be divided into 3 types: the coniferous forest, the deciduous broad-leaved forest and the deciduous broad-leaved shrubland.The transition zone is a favorable location for resource plants. According to their utilization, resource plants may be divided into 4 groups. Based on the investigation, there are 234 species of industrial plants, 141 species of medicinal plants, 124 species of edible plants and 46 species for floriculture. In addition, some idioplasmic plants also inhabit in the region.According to the distribution, habitat, number of population, utilization of resource in the region, as well as qualitative and quantitative criterion, the rare and endangered plants are divided into three classes. The first class has 6 species;the second class includes 6 species;8 species belong to the third class. 6 species are categorized into the of national threatened plants, which are Juglans mandshurica, Phellodendron amurense, Acanthopanax senticosus, Populus pseudomaximowiczii, Jilia amurensis and Ulmus lamellosa.