Population Structure and Spatial Distribution Pattern of Emmenopterys henryi in Liankang Mountain Natural Reserve, Henan Province

To study the population structure and distribution pattern of Emmenopterys henryi in Ta-pieh Mountain at the south of Henan Province, a typical sample method was used to investigate the E. henryi population in Liankang Mountain Natural Reserve. The results show that: (1) The age structure of the E. henryi population showed a certain degree of skewness distribution, and the population structures in different plots were different. The population presented the common characteristics of small number of young individuals, concentrated number of middle aged individuals and lacking of big individuals. (2) The survival curve was close to the DeeveyⅠtype, such as low mortality and very few individuals at age Ⅰ and Ⅱ, but the mortality rates at age Ⅶ and Ⅷ were high resulting in the concave and breakpoint of the survival curve. Both individual survival number (a_x) and life expectancy (e_x) decreased with the increasing of diameter-class after age Ⅱ, e_x showed a certain fluctuation change with the increasing of diameter-class, suggesting a poor stability of the population. (3) The results of the analyses by using various coefficients and indices that the spatial pattern of the E. henryi population showed clumped distribution, while there were some differences in the clustering degree among different populations. (4) The E. henryi population in Liankang Mountain was generally in a disadvantageous habitat, and its ability to occupy ecological space in ecosystems was poor, so that, it is suggested to carry out seedling breeding and ex situ conservation to promote effective protection and healthy continuation of the endangered population.