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Danxia landform is recognized as an unique type of landform by Chinese geomorphologist. During the 1930s, Mr Chen Guoda, a famous professor in the field of geology, after making a comprehensive research at Danxia Mountain and Red rocky mountains in South China, named this kind as "Danxia landform", and soon, the idea was accepted by reaserchers in the field. After that, any landform with red terrestrial clastic rock and characterizing bare and red cliff is taken as Danxia landform.Danxia landform plays a inalienable role in many picturesque sceneries. For its aesthetic value and extraordinary meaning in geology, Danxia landform of China have associated to apply for World Natural Heritage. Hunan have a large area of Danxia landform, the red beds, which can form to Danxia landform, accounting for 11.7% of Hunan’s total area. At present, there are few research on the plants of Danxia landform, which far behind the development of tourism. By means of investigating of Danxia landform plants in Hunan, this thesis covers some reports about the plants of Hunan Danxia landform, wishing to provide a reasonable and convincible theory for the protection of these type plants and development of tourist resources.From April to October in 2008, based on investigating of Danxia landform plants at the place of Wanfoshan (in Tongdao), Langshan (in Xinning), Shiniuzhai (in Pingjiang), Huanxi (in Chaling), Guanzhuang and Wuqiangxi (in Yuanling), collecting plant specimens, taking photograph and taxonomic research, the list of seed plants in Hunan Danxia landform has been compiled. The statistics and comparatively intensive analysis were given at the level of family and genus. The vegetation types are classified and the characteristics of Danxia landform plant also summarized. The mian research results can be illustrated as follows:(1) There are 1130 species (including some varieties and subspecies) of wild seed plants belongsing to 588 genera and 163 families. Among them, 7 families, 10 genera, 13 species are Gymnospermeae; 156 families, 588 genera, 1117 species are Angiospermae.(2) According to the analytic study of distribution patterns of family, the tropical nature is stronger than temperate. Meanwhile, according to that of genus, the percentage of Pantropic reaches peak, followed by North Temperate and East Asia. Generally speaking, the temperate genera owns their advantages. (3) The vegetation can be divided into 3 vegetation type groups, 7 vegetation types, 15 formations. More detailed analysis and description on each formation are described in this thesis.(4) The Danxia landform plants in Hunan are characterized by abundant xerophytes, flourishing liana, diversified Orchidaceae, gathering rare and endangered wetland plants, plenty of endemic plant.(5) Seven species are reported as new records in Hunan, they are Saxifraga mengtzeana, Saxifraga cernua, Wikstroemia angustifolia, Exochorda racemosa, Lysimachia klattiana, Amorphophallus sinensis, Malaxis microtatantha, and Malaxis is a new genus in Hunan.(6) Proposals have been figured out in this thesis for the protection of Danxia landform plant.
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