湖南丹霞地貌区蕨类植物多样性

丹霞地貌是有别于石灰岩地貌和花岗岩地貌的特殊地貌类型,发育着较为独特的植被类型和植物区系。我们于2007-2010年间对湖南新宁崀山、茶陵浣溪、平江石牛寨、资兴程江口、浏阳达浒、通道万佛山、沅陵五强溪夸父山、溆浦思蒙等地丹霞地貌的蕨类植物进行了广泛调查,报道了湖南丹霞地貌区蕨类植物31科66属183种的详细名录。其中,无腺姬蕨(Hypolepis polypodioides)、隐囊蕨(Notholaena hirsuta)、仙霞铁线蕨(Adiantum juxtapo-situm)、百山祖短肠蕨(Allantodia baishanzuensis)、肉质短肠蕨(A.succulenta)、骨碎补铁角蕨(Asplenium ritoense)、钝齿耳蕨(Polystichum deltodon var.henryi)、无盖耳蕨(P.gymnocarpium)、单羽耳蕨(P.simplicipinnum)、二型肋毛蕨(Ctenitis dingnanensis)等9种为湖南新记录种。湖南丹霞地貌的蕨类植物种类组成主要有鳞毛蕨科、蹄盖蕨科、水龙骨科、金星蕨科、卷柏科、铁角蕨科等较大科及鳞毛蕨属(Dryopteris)、卷柏属(Selaginella)、铁角蕨属(Asplenium)、短肠蕨属(Allantodia)和凤尾蕨属(Pteris)等较大属。生态适应特点分析表明丹霞地貌既有喜钙质土的种类,也有喜酸性土的种类,仙霞铁线蕨和无盖耳蕨可能是丹霞地貌的特有植物,因而具有石灰岩地貌蕨类植物区系和花岗岩地貌蕨类植物区系之间的过渡性特点。建议将垫状卷柏(Selaginella pulvinata)、福建观音座莲(Angiopterisfokiensis)、仙霞铁线蕨、骨碎补铁角蕨、鞭叶蕨(Cyrtomidictyum lepidocaulon)、无盖耳蕨等种类列为丹霞地貌蕨类植物中的优先保护种类,将通道万佛山三十六湾、湖南沅陵夸父山列为丹霞地貌蕨类植物的优先保护地区。

The pteridophyte diversity of the Danxia landform in Hunan Province, China

The Danxia landform is a unique landscape type with a high level of floral endemism. Herein, we report the fern flora of Danxia landform in Hunan Province. We complete comprehensive surveys of pteridophytes in the Danxia landform areas of Hunan between 2007 and 2010. We report an annotated species checklist in this paper, including 183 species and 66 genera in 31 families. Nine species, including Hypolepis polypodioides, Notholaena hirsuta, Adiantum juxtapositum, Allantodia baishanzuensis, A. succulenta, Asplenium ritoense, Polystichum deltodon var. henryi, P. gymnocarpium, P. simplicipinnum and Ctenitis dingnanensi, are reported as new records to Hunan. The families with more than 10 species include the Dryopteridaceae, Athyriaceae, Polypodiaceae, Thelypteridaceae, Selaginellaceae and Aspleniaceae, and the genera with more than 8 species are Dryopteris, Selaginella, Asplenium, Allantodia and Pteris. This list not only includes calciphilous ferns, but also acidophilous and endemic ferns restricted to the Danxia landform (e.g., A. juxtapositum and P. gymnocarpium). It is hypothesized that the fern flora of the Danxia landform may be anintergradation type between Karst landform and granite landform. Lastly, we provide recommendations for the longterm protection of the floral diversity of the Danxia landform.