极小种群植物博罗红豆的种内和种间竞争

Interaspecific and Intraspecific Competitions of Ormosia boluoensis with Extremely Small Population

为了探讨惠州特有极小种群博罗红豆群落内物种间的竞争关系,该研究通过对广东象头山国家级自然保护区博罗红豆群落内的59株对象木及522株竞争木开展调查,运用Hegyi单木竞争模型分析了博罗红豆种内与种间竞争强度。结果表明,(1)博罗红豆的种内竞争强度(335.828)大于种间竞争强度(217.745),其竞争压力主要来自于种内竞争。(2)博罗红豆伴生树种有28种,其竞争指数大于10的树种有密花山矾>网脉山龙眼>甜槠>鼠刺>密花树>赤楠>华润楠>红淡比>柯。(3)博罗红豆对象木胸径与种内、种间和林分的竞争指数之间均服从幂函数关系,随着博罗红豆胸径增大,其种内、种间、林分的竞争指数逐渐降低,当对象木胸径小于3 cm时,竞争指数最高;随着对象木胸径的增长,竞争指数逐渐降低并趋于稳定,种间竞争与林分竞争符合相同的规律。

In order to explore the competitive relationships among species within the unique extremely small population of Ormosia boluoensis community in Huizhou,this study conducted a survey of 59 target trees and 522 competing trees in the Ormosia boluoensis community of Xiang tou mountain National Nature Reserve in Guangdong.The Hegyi single tree competition model was used to analyze the intensity of intra-and inter species competition in Ormosia boluoensis.The results indicate that(1)the intra specific competition intensity of Ormosia boluoensis(335.828)is greater than the inter specific competition intensity(217.745),and the competition pressure mainly comes from intra specific competition.(2)There are 28 accompanying tree species of Ormosia boluoensis,and the tree species with a competition index greater than 10 are Symplocos congesta>Helicia reticulata>Castanopsis eyrei>Itea chinensis>Rapanea neriifolia>Syzygium buxifolium>Machilus chinensis>Cleyera japonica>Lithocarpus glabra.(3)The competition index between the diameter at breast height of the target wood and the intra-,inter-,and stand competition indices all follow a power function relationship.As the diameter at breast height of the target wood increases,the competition index gradually decreases.When the diameter at breast height of the target wood is less than 3 cm, the competition index is highest;As the diameter of the target wood increases, the competition index gradually decreases and tends to stabilize, and interspecific competition and stand competition follow the same pattern.