中国种子植物特有属在秦岭的地理分布及其特征

THE GEOGRAPHICAL DISTRIBUTION AND FLORESTIC CHARAC TERISTICS OF GENERA ENDEMIC SPERMATOPHYTES TO CHINA IN QINLING

Qinling situated in Central China, is an important distributional limit of endemic to China towards the north. There are 36 genera endemic Spermatophytesto China in Qinling range.Among them 14 are monotypic, 17 are oligotypic and 5 are polytypic ones. The former two types tabe a great part of the total and together make up more than 86.1%. Most of them are ancient-originated. Few are relatively young ones. The geographical elements of them are very complex aud varied. Concerning to the modern distributional pattern, it showes that Qinling has maxium genera endemic Spermatophytes to China common with Southwest China geographical group, especially with Sichuan province. The Central China geographical group (eg. Hubei province) is the second place and minimum with North China geographical group. The genera endermic Spermatophytes to China distributied in Qinling show obvious temperate charateristics. The horizontal distributions of them are very uneven. So far as the vertical distribution, most of them are concentated in intermediate altitude. The floristic characteristics and the distribution of genera endemic in Qinling are very different between east and west terminal. The reaches of the three rivers(Beilong Jiang, Beishui Jiang and Jialing Jiang) in west terminal is one of the most important refuges and migrating route stoward north of genera endemic Spermatophytes to China.