珍稀濒危植物金花茶的群落学特征

据1600m2样方调查,金花茶集中分布的群落中,胸径大于1cm的立木植物有119种,隶属40科80属。其中以热带分布的属占绝对优势,占总属数的92.5%,充分说明群落的热带性质。不同海拔高度的4个群落均为次生林类型,外貌常绿,结构相对较简单,乔木层可分2~3层,村边林群落高度可达16~20m,乔木分3层,保护区内群落高度10m左右,乔木分2层。群落优势种较明显,粗糠柴、降真香等在各群落均为优势种。群落单位面积内的种数和个体数目均较大,少见大径级立木,可见群落处于强烈的进展演替阶段。群落的物种多样性指数和生态优势度均较高,但群落具较低的均匀度,说明群落仍处于演替的中早期,且优势种较明显。

Phytocoenological feature of the rare and endangered plant Camellia nitidissima

According to the investigations conducted in a field of 4 sampled plots with a total 1 600 m2,119 plant species (diameter at breast height (DBH) were more than 1 cm) belonging to 80 families and 40 genera were recorded in the community of C.nitidissima. 92.5% of these genera are tropical,which therefore showed the tropical characteristic of the community. All of 4 communities located in different altitudes were secondary forest type. They had an evergreen physiognomy with simple structure. Canopy of trees could usually be distinguished into 2-3 layers. The height of 2 communities near the village was 16-20 m. canopy of arbor could be sorted to be 3 layers,of which there are 2 layers in the conservation district with 10cm in height. Mallotus philippensis and Acronychia pedunculata were dominant species in all communities investigated. There were a large number of individual plants and species in the community of C.nitidissima in a unit area. The trees with big size-class in all communities investigated were rare. Therefore, these communities of C.nitidissima were in a rapid processing of succession. Otherwise,the diversity index and ecological dominance index of these communities were higher but the uniformity was lower,indicating that these communities were at the succession of the initial to medium phase with marked dominant species.