川西雅砻江上游地区蕨类植物区系研究

Pteridophytic Flora of the Upper Reaches of the Yalong River in Western Sichuan Province

雅砻江上游地区处青藏高原东南部,横断山区西北部,在中国植物区系划分中属于泛北极植物区,中国—喜马拉雅森林植物亚区中的横断山脉植物地区.该区域蕨类植物有20科,以世界分布型为主,共有10科,热带分布科7科,温带分布科3科.该区域蕨类植物有29属,划分为8个分布区类型,世界分布6属,热带成分8属,温带分布13属,中国特有分布2属.该区域蕨类植物有71种,其中中国特有分布34种,占该区蕨类植物总种数的47.89%,隶属于13科20属.该区域蕨类植物的区系特点表现为:优势科、属不明显,科内属、种贫;属、种的特有化程度高;植物区系交叉过渡明显.

The upper reaches of the Yalong River is located in the southeastem Qinghai-Tibet Plateau and the northwestem Hengduan Mountains. In the Flora of China, this region belongs to the Hengduan Mountains plant region of China-Himalayan forest plants in the fall of the Pan-Aretic vegetation zones. In this valley section there are 20 families of Pteridophyte. The main element is the world distribution type with 10 families. Families of the tropical distribution type are more than the temperate distribution type, 7 families and 3 families, respectively. In this valley section there are 29 genera of Pteridophyte, which can be divided into 8 types. The world distribution type has 6 genera. The tropical distribution type has 8 genera. The temperate distribution type has 13 genera. The endemic distribution type to China has 2 genera. In this valley section there are 71 species of Pteridophyte, of which the endemic distribution type to China has 34 species with 13 families and 20 genera, making up 47.89 % of the total species. Floristic characteristics of this valley section indicats that the preponderant families and genera are not predominance. The number of Genera and species is very indigent in families. Genera and species lack of notable endemism. The cross and transition of flora is very obvious.