中国森林种子植物区系的特征

本文主要根据中国种子植物区系研究的最新资料，简要介绍中国现代森林种子植物区系的多样性、地理成分、区系性质及地区差异等特征，供森林研究和中国生物多样性研究参考。

CHARACTERISTICS OF SPERMATOPHYTE FOREST FLORAS IN CHINA

In this paper an overview is given of the flora of China which comprises some 30 560 species in 3 150 genera of 343 fairlies of seed plants, being 13%, 25% and 61 % of the world 's flora, respectively. Woody plants of China consist of some 2 000 species in 1 200 genera of 187 families, and shrubs comprise 6000 species, herbaceous species are included in 156 families. All of them are mostly the forest components except for hydrophyte with 26 families and some alpine plants. The distribution patterns of floristic elements is tabulated according to Wu Cheng-yih's "The Areal Types and Subtypes of Chinese Genera of Seed Plants" with some variation. The distribution of the families are classified in 14 areal types with 17 subtypes, in which tropical families, exclusive of cosmopolitan one, amount to 190, being 66.4% of total fairlies in China. The distribution of genera lies in the regions of 15 areal types with 33 subtypes, in which 1 542 genera (notincluding 106 cosmopolitan genera) are tropical, being 50.7% of total genera in China. The ratio of tropical genera to temperate genera is about half-and-half. Thus, it could be recognized that the forest flora of China is of subtropical nature, an intermediate flora between tropic and temperate floras. China has a large number of endemic genera and species amounting to 251 and 17300, respectively, which represent 8.2% and 60% of the total genera and species in China, respectively. Floristic differences from north to south,and from east to west of China are obvious. The flora of Heduan Mountain region is extremely diverse, which possesses some 7954 species in 1 325 genera of 226 fairlies, being 26%, 42.l% and 65.9%, respectively, of the total taxa in China, and having a large number of endemic taxa. The flora in central region of China is a typical subtropical flora due to enriched elements of East Asia and a large number of endearic plants amounting to about 4035 species. Flora in the south part of China is tropical flora in nature as it is bounded by the north part of Tropical Asia. In arid areas of North-west China, however,forest flora occurs only by rivers, comprising Ancient-Mediterranean elements and having very limited amount of species.