关键词: 种子植物区系, 洮河流域, 甘肃

Abstract: The Taohe river in Gansu province is located in the connuent zone of Loess Plateau and Qinghai-Xizang plateau, where the seed plants are relatively abundant in species. According to preliminary statistics, the seed plants in this area comprise 1346 species (incl. ssp. and var.), 448 genera and 100 families. The primary characteristics of the spermatophyte flora from the Taohe river are: rich in species, complex in geographical elements, having an extensive connection with nearby fioristic areas, but with temperate elements as absolute predominance, basically of N temperate in nature, and its floristic elements showing very obvious transition. On the basis of the distribution of endemic species and some physiographical features, the flora of middle-upper reaches of Taohe river belong to the subregion of NW Sichuan, S Gansu and SE Qinghai of Hengduan mountain, and the lower reaches of the river to the subregion of Loess Plateau of North China.

Key words: Spermatophytic flora