重庆武隆天生桥种子植物区系研究

重庆武隆天生桥是国家4A级风景名胜区，处于云贵高原大娄山褶皱带与武陵山系的过渡地带。对该区植物从科、属和种的分布区类型进行了统计分析，另外将该区区系特征与其他几个地区进行了对比分析。结果表明：①该区内有种子植物115科、475属、1292种。②大、中属共有37属，仅占总属数的7．79％，但所含种数达389种，占总种数的30．11％。说明本植物区系中优势属较为明显。③从种子植物科属分布区类型所占比例来看，该地区区系性质以热带成分占优势，其中热带分布属214属，占总属数的50．71％，这一特点与当地的环境特点是密切相关的。④区系分析表明，温带分布类型也占相当优势，有温带分布属203属，占总属数的48．10％，说明该地区区系性质具有热带到温带过渡的性质。⑤中国特有种丰富，共有881种，占总种数的68．83％。⑨经对比分析和聚类分析表明：该区与相距较远地区属的相似性系数较低，表明区系上联系较为疏远；而与邻近的几个地区属的相似性系数较高，特别与西南地区植物区系联系紧密。

A Floristic Study of the Seed Plants on Tianshengqiao Scenic and Historic Interest Area in Chongqing City

The Tianshengqiao Scenic and Historic Interest Area is situated in south of Chongqing. From the statistics and analysis of the areal-types of families, genus and species basing primary survey of the region,the composition,characteristics and geographic element of the seed plant flora in the region were report in this paper.The results indicate as follow: (1) The flora was considerably rich. It is now known there are 1292 species in 475 genera and 115 families of seed plants in the region. (2) The dominant genera are prominent.The 37 dominant genera containing more 5 species contain 389 species which account for 30.11% of overall species. (3) Based on the analysis of the flora of families and genera construction in the area,it is indicated that the flora has typical characteristics of tropic distribution compositions, especially in the level of genus.There are 214 genus in the area which account for 50.17% of overall genera.The characters is closely related with the local environment. (4) The temperate distribution compositions of genera play an important role in the construction of the flora. There are 203 genera in the area which account for 48.10% of overall genus. (5) Chinese endemic species of seed plants in this area are abundant. (6) Comparative and clustering analysis can clearly reflect the differences of flora,the result indicate Tianshengqiao are much more closely allied to Simianshan, Zigui and Wulingshan than to Luyashan and Wuzhishan in flora, and the flora of seed plants in this region relates the flora of Southwest of China tightly.