广东石门台自然保护区的蕨类植物区系分析

通过野外调查和标本参考,广东英德石门台国家自然保护区蕨类植物区系共含47科, 96属, 293种。分析表明:(1)热带、亚热带分布性质的科为主(31科),占66.0%,非热带性分布科(16科),占34.4%。(2)热带、亚热带性质的属占优势(64属,占66.7%),其中泛热带分布属(24,25.0%)和热带亚洲分布属(19, 19.8%)是最重要的分布类型。世界分布属占26.4%,温带分布属很不明显,占7.3%。属的这种分布格局,显示出该区蕨类植物区系从热带成分向亚热带成分的渗透和过渡。(3)热带、亚热带分布种(139种)所占比例最大(47.4%),其中以热带亚洲性质的占优势(103, 35.2%);温带成分占较大的比例(34.1%)。种的分析结果与属的分析结果相差很大,出现区系相互渗透的现象。(4)在种的相似性比较上,与东部车八岭的相似性最高(38.5/59.2);与西部大瑶山种的相似性最低(21.5/35.6)。该区的蕨类植物区系与周围地区关系较为密切。

A study on the fern flora of Shimentai Natural Reserve, Guangdong, China

Based on our survey and specimen examination, 293 ferns in 96 genera and 47 families are recorded in Shimentai Natural Reserve, Guangdong, China. A detailed floristic analysis shows: (1) The tropical and subtropical families are dominant (31 families), which constitute 66.0% of the total families, and the non-tropial familes(16 families) constitute 34.4% of total families. (2) The percentages of the tropic-subtropic, cosmopolitan and temperate genera in fern flora of Shimentai natural reserve are 66.7%, 26.4% and 7.3%, respectively. The pantropical genera (25.0%) and the tropical Asia genera (19.8%) are the most important types. The above distribution pattern reveals the transitiveness of the elements from tropical to subtropical. (3) The percentages of the tropic-subtropic, temperate, endemic to China, cosmopolitan and endemic to zone species in fern flora of this reserve are 47.4%, 34.1%, 13.7%, 3.8% and 1.0%, respectively. So it is very different from the analysis of the genera's distribution. And the floras are being in transitiving. (4) In the 5 areas, the genetic relationship of Shimentai Nature Reservation's ferns are intimate to HongKong's (70.4/82.8: Kjaccard/Krober), and are distant to Longqishan(58.7/74.9). Originally, the ferns of Shimentai Nature Reservation are ancient. And Shimentai area lies in the interface of south Asia subtropical and middle Asia subtropical floristic area.