广东阳春百涌自然保护区桫椤科植物资源调查

A Survey on the Cyatheaceae in Baichong Nature Reserve in Yangchun, Guangdong, South China

广东阳春百涌自然保护区属云开山脉,区内桫椤科植物资源丰富,但具体种类及其资源量并无准确资料,为此我们开展了相关野外调查和统计。调查表明,保护区内共有4种桫椤科植物,即桫椤Alsophila spinulosa、大叶黑桫椤Gymnosphaera gigantea、小黑桫椤G.metteniana和黑桫椤G.podophylla。依据保护区内桫椤科植物主要沿林道分布的特点,提出了按林道长度估算资源量的方法,据估算,保护区内有桫椤约900株,大叶黑桫椤约1.5万株,小黑桫椤约320株,黑桫椤约4500株。阳春百涌保护区是华南地区大叶黑桫椤的主要保存地。

Baichong Nature Reserve, a mountainous region within Yunkai Mountains, is situated in western Guangdong, China where the scaly tree ferns are very common. However, we do not have a list of species, nor an evaluation of the amount of individuals for each species of Cyatheaceae in the reserve. To know the exact species and the resource amount of them we conducted a detailed survey in Baichong Nature Reserve in April 2016. As a result, four species are detected in the reserve, namely Alsophila spinulosa, Gymnosphaera gigantea, G. metteniana, and G. podophylla. Based on the fact that the tree ferns are restricted to pathways in forest, including the habitats just on and beside the pathways and the valleys distributed along pathways, we develop a new method to calculate the resource amount of each species. The calculating method can be summarized as adding up the number of plants according to the length of forest pathways where tree ferns grow. Based on the calculating method and the data from 10 quadrats and two belt transects, the resource amount of the four species are evaluated as： ca. 900 adult individuals for A. spinulosa, 15 000 for G. gigantea, 320 for G. metteniana, and 4500 for G podophylla. It proves that Baichong Nature Reserve is one of main conserving places for G. gigantea in southern China.