Trunk growth regular and age structure of Disanthus cercidifolius var. longipes in Jiangxi Guanshan National Nature Reserve

Wang Guobing;Xu Dinglan;Wu Qinshu;Yao Xiaohua;Lin Guojiang;Yang Qingpei;Administration of Jiangxi Guanshan National Nature Reserve;Forestry College of Jiangxi Agricultural University;Forestry Bureau of Xinhuang County;

Jiangxi Guanshan National Nature reserve;;Disauthus cercidifolius var.logipes;;growth rule;;age structure

Disanthus cercidifolius var. longipes is an endemic and endangered plant in China, age defining is foundmental for its bio-ecology research. In this paper, the relationship between height, DBH and age was first established based on data of ramet analysis, and then the population life table was compiled. The results showed that the height and age relationship agreed with the Logstic equation H=5.18/(1+17.58e~(-0.204t)), DBH and age relationship with Schumacher equation D=16.80e~(-27.82/t).This tree is a slow-growing species with maximum height growth of 0.26 m·a~(-1), the maximum DBH of 0.33 cm·a~(-1). The age structure of population in this region is not regular, the seeding and sapling was relative less but their life expectancy was high, up to about 40 a, ramets of 50~60 a began to fail. The results provided basis for age estimation Disanthus cercidifolius var. longipes, and also shed light on the population dynamics.