广州市蕨类植物物种多样性研究

依据文献、标本与野外调查,简要回顾了历史上记录的广州蕨类植物,阐明了广州目前分布的蕨类植物的种类、区系特点、生态与地理分布、以及珍稀蕨类植物的种类与保护现状.广州地区有蕨类植物37科82属176种,其中乔芒萁(Dicranopteris gigantea)、刺边膜蕨(Hymenophyllm spinosum)和裸果鳞毛蕨(Dryopteris gymnosora)为广东分布新记录.广州蕨类植物区系以金星蕨科(Thelypteridaceae)、鳞毛蕨科(Dryopteridaceae)、水龙骨科(Polypo-diaceae)、蹄盖蕨科(Athyriaceae)和风尾蕨科(Pteridaceae)的植物最为丰富,没有本地特有种,亚洲热带亚热带分布成分和东亚分布成分占绝对优势.这176种蕨类植物中,约80%的种类生活在密林阴湿生境,约20%生活在疏林或灌草丛干旱生境,只有2种水生蕨类植物.在水平分布上,广州蕨类植物呈北多南少的分布格局,约90%的种类汇集在广州东北部的从化山区,74种在广州仅见于该山区.从物种多度上看,个体数量多(Cop2)的有33种,尚多(Cop1)的有48种,稀少(Sp)的有53种,很少(So1)的有41种.华南马尾杉(Phlegmariurus austrosbzicus)、福建观音座莲(Angiopteris fokiensis)、刺边膜蕨(Hymenophy llum spmosum)、粗齿桫椤(Alsophila denticulata)、小黑桫椤(A.m etteniana)、黑桫椤(A.podophylla)、桫椤(A.spinulosa)、水蕨(Ceratopteris thdictroides)、羽裂叶双盖蕨(Diplazium tomitaroanum)、闽浙圣蕨(Dictyocline mingchegensts)、微毛凸轴蕨(Metathelypteris adscendens)、峨眉茯蕨(Leptogramma scdlanll)、苏铁蕨(Brainea insignis)、珠芽狗脊(Woodwardia prolifera)和黑鳞复叶耳蕨(Arachniodes nigrospinosa)等15种被评估为广州的珍稀植物,它们亟待有效的保护.

A Biodiversity Study on the Pteridophytes from Guangzhou City, Guangdong

In order to understand the modern pteridoflora of Guangzhou, Guangdong Province, we briefly reviewed the recorded pteridophytes in history and made extensive explorations in this area in the last two and a half years. As a result, 176 species belonging to 82 genera in 37 families are now recorded for Guangzhou. Three species, Dicranopteris gigantea, Hymenophyllum spinosum, and Dryopteris gymnosora, are newly recorded from Guangdong. The five species-rich families are Thelypteridaceae, Dryopteridaceae, Polypodiaceae, Athyriaceae and Pteridaceae. The geographical distribution of the species shows that this flora mainly consists of tropical & subtropical Asian and eastern Asian elements but lacks local endemics. About 80% of the species of this flora grow in humid habitats of dense forest, about 20% occur in relatively dry habitats such as sparse forest and shrub in roadsides, and two species are hydrophytic. Regarding the horizontal distribution in Guangzhou, only a very small proportion of the species occurs in the southern and central areas, but about 90% grow in the montane area of Conghua in northeastern Guangzhou, from which 74 species only occur in Conghua. Within Guangzhou, the abundance of the 176 species can be classified in four groups, i.e., 33 species are Cop (copiosae)2, 48 are Cop1, 53 are Sp (sparsal) and 41 are Sol (solitariae). Fifteen species, i.e., Phlegmariurus austrosinicus, Angiopteris fokiensis, Hymenophyllum spinosum, Alsophila denticulata, A. metteniana, A. podophylla, A. spinulosa, Ceratopteris thalictroides, Diplazium tomitaroanum, Dictyocline mingchegensis, Metathelypteris adscendens, Leptogramma scallanii, Brainea insignis, Woodwardia prolifera and Arachniodes nigrospinosa, are evaluated as rare and endangered in Guangzhou but not under any effective protection at present.