元宝山冷杉(Abies yuanbaoshanensis Y .J .Lu et L.K .Fu)特产广西, 是种群数量极少的濒危物种。 根据调查资料, 采用 Hegyi 提出的单木竞争指数模型 CI =∑Nj =1(Dj/ Di)· 1/Lij对元宝山冷杉群落的种间、种内竞争强度进行定量分析。 结果表明:元宝山冷杉种内竞争较之与其伴生树种间的竞争剧烈;竞争木对对象木的竞争强度与对象木的胸高直径服从幂函数关系 CI =AD^B , 竞争强度随对象木个体的增大而减小。 当元宝山冷杉胸高直径达到 35 ～ 40cm 后, 竞争强度变化不明显。 利用模型预测了元宝山冷杉种内和种间的竞争强度。
 

Abies yuanbaoshanensis Y .J .Lu et L .K .Fu is a rare and endangered plant , it is only found on
Yuanbaoshan Mountain in Guangxi , China .By using Hegyi , s competition index model for individual tree 〔CI=∑Nj =1(Dj/ Di)· 1/ Lij〕 , the intraspecific and interspecific competition in A .yuanbaoshanensis community were investigated .The results show that intraspecific competition of A .yuanbaoshanensis is more intensive than interspecific competition .The competition intensity of competitive tree against objective tree and the size of objective tree fit power function CI =AD^B , and competition intensity decreases with the increase of the size of objective tree .The CI change is not significant when the DBH of A .yuanbaoshanensis reaches 35 -40 cm .The model can simulate and predict the intraspecific and interspecific competition among Abies yuanbaoshanensis community in Guangxi .