Plant Diversity Study On Cyclobalanopsis Chungii Forest

There are 1029 species of seed plants belonging to 581 genera in Cyclobalanopsis chungii Forest nature reserve which respectively accounts for 30．82% and 50．43% to the whole province and the species diversity is high based on the field survey and identification to the plants of this area. There are many first-class and second-class national-protected plants and Fujian province's key-protected plants, and there are 25 single-species genera and 15 China special species. According to Wu Zhengyi's division on the generic geographical distribution composition of China seed plants, the seed plants in this area can be divided into 14 geographical distribution compositions, in which the pan-tropic plants are maximum containing 137 genera and 285 species. Evidently, the tropic plants are overwhelming here in spite of there are still a variety of plants of temperate zone. Compared with its neighboring eleven every broad-leaved forests in East China and South China, the floral distribution in this area along with those of the same province around it have a clear geographical division with others. Studyed from a far-ranging scope, the distribution character of this area is more similar to that of East China.In the same time, combined with the analysis of environmental factors, RAPD technique was applied on the dominant Cyclobalanopsis. chungii population to study its genetic diversity, total 76 pieces of bands were expanded from the selected 10 RAPD primers, thereinto 37 pieces of bands are polymorphism bands, which accounts for 48．68% of all.It indicated that there is considerable genetic diverity among Cyclobalanopsis chungii populations of different samples. The seven Cyclobalanopsis chungii populations can be divided to three kinds based on the genetic distances of different samples, which was accordant with the results of correlation analysis on environmental factors, so it indicated that the populations' genetic diversity has highly relativity with environmental factors. At the same time, it was found that the interactions of all of the environmental factors were together responsible for the genetic aberrances in which the principal contributing environmental factors are soil organic composition content, soil PO content and habitat directions.And even if there is notable difference on one environmental factor, considerable impact is produced on genetic diversity. Consequently closely genetic diversity produced among populations of the same differences which expresses as closer genetic distances.