中国泥盆纪维管植物的组成与古地理分布

Constitution and palaeogeographical distribution of the Devonian vascular plants in China

依据泥盆纪早、中、晚3个时期的中国岩相古地理图及中国泥盆纪植物已有的资料,绘制出中国泥盆纪这3个时期的植物古地理分布图。中国泥盆纪海侵的主要方向是从中国西南部的云南地区(早泥盆世)逐渐向长江中游的华中地区(中泥盆世)及长江下游的华东地区(晚泥盆世)发展。中国泥盆纪维管植物在南方的分布是随着海侵,逐渐向华中及华东地区扩展,由早泥盆世西南地区的云南、四川、贵州,以及广西和湖南南部等地区,发展至中泥盆世云南、四川、贵州、湖南的中北部以及湖北的南部地区,在晚泥盆世的分布范围扩大到广东、湖南、湖北、江西、安徽、浙江以及江苏等地区。泥盆纪维管植物在北方的分布范围较小,从中泥盆世才开始出现,主要分布在新疆的北部,晚泥盆世在宁夏等地区也有分布。中国泥盆纪3个时期陆地维管植物各个种类所占的百分含量表明,早期的植物主要以较为原始的莱尼蕨类、工蕨类以及前石松类为主,中期石松类占优势,到了晚期石松类依然占优势,而楔叶类、真蕨类以及前裸子植物开始繁盛。

With the knowledge of the Devonian sediment distribution and the Devonian plant localities in China, we compiled the palaeogeographic maps of the Early, Middle and Late Devonian plant distribution in China. According to these maps, we may find that the plants in the Early Devonian were distributed in Yunnan, Guangxi, and Hunan in southwest China and migrated to the middle reaches of the Yangtze River in the Middle Devonian and to the lower reaches of the Yangtze River in the Late Devonian. In North China, the Early Devonian plants were not recorded, but the Middle Devonian plants were found in northern Xinjinag. The plants migrated to the Qilian Moutains and some areas in Ningxia in the Late Devonian. The percentage of every kind of plants in the three ages of Devonian was calculated. The plants of zosteropbyllophytes were the dominant types in the Early Devonian floras, associating with rhyniophytes and prelycopods. The lyeopods became the dominant plants in the Middle Devonian floras. In the Late Devonian, lycopods still dominated, and sphenphytes, ferns and pteridosperms developed quickly.