连州上柏场报春苣苔所处岩洞植物区系特征

Characteristics of flora with Primulina tabacum within a lime stone cave at Shangbaichang,Lianzhou

为了解国家I级重点保护植物报春苣苔(Primulina tabacum)种群所处生境的植物多样性和区系特征,对广东连州上柏场石灰岩洞内及洞口附近的维管植物进行了调查。经采集鉴定标本,统计出上柏场岩洞有维管植物66科100属115种,包括报春苣苔、金荞麦(Fagopyrum dibotrys)2种国家重点保护野生植物,连县唇柱苣苔(Chirita lienxienensis)1种连州特有植物,圆叶乌桕(Sapium rotundifolium)等多种石灰岩特征植物。种子植物科、属的区系成分以泛热带分布为主,而种的区系成分以东亚分布、中国特有分布和热带亚洲分布为主。生活型谱以多年生草本植物种类最多;由于洞穴高度、光照等的限制,群落的垂直结构特征不明显。研究结果表明,上柏场岩洞种类密度较高,其特殊的种类组成与其亚热带地理位置和特殊的石灰岩地貌生境相适应。

A field survey of plant diversity within a lime stone cave at Shangbaichang, Lianzhou, Guangdong where the national key protected species Primulina tabacum population grows was made to investigate the flora characteristics. After collecting the plant samples and detected, there are 66 families, 100 genera, and 115 species of vascular plants were found, including two wild national key protected species of Primulina tabacum and Fagopyrum dibotrys, one species of Chirita lienxienensis endemic to Lianzhou city, and some characteristic species to lime stone such as Sapium rotundifolium. The floristic composition of plant family and genus are mainly in pan-tropic areal-types, while the species floristic is mainly made up with Asia distribution, Endemic to China, and tropical Asia areal-types. Meanwhile the life-form spectrum mainly consists of Perennial herbs. As the cave height and the sunlight are limited, the vertical structure is not typical. The present living statue and protect countermeasure ofPrimulina tabacum are also discussed in this paper. The results showed that the species density is relative higher, and the special species composition is adapted to the subtropical geography location and the special lime habitat.