Population Structure and Dynamic Characteristics of Rhododendron griersonianum:A Plant Species with Extremely Small Populations
Rhododendron griersonianum is a plant species with extremely small populations(PSESP)in China and is listed in the List of National Key Protected Wild Plants.In order to clarify the community characteristics of Rh.griersonianum and to evaluate the survival potential of its populations,we conducted a plot survey,investigated the species composition,compiled a static life table for the Rh.griersonianum populations,and analyzed the diameter structure and population dynamics.The results showed that:(1)A total of 17 woody species with important values＞1％were recorded in the plots,among which Quercus augustinii,Lithocarpus craibianus,Vaccinium duclouxii and Pi-nus yunnanensis were the dominant species of the community.(2)The largest number of Rh.griersonianum individu-als was in age class Ⅱ,which accounted for 17.06％of the total individual number.The number of individuals in-creased as the age class increased.The diameter class structure showed a'spindle'shape,and the age structure fol-lowed a recession type.(3)The survival curve of Rh.griersonianum was close to the distribution of Deevey I.The highest mortality rate of the population occurred in age class X,with a mortality rate of 40％.The dynamic change index(Vpi)and the dynamic change index under external disturbance(V'pi)were both＞0,but V'pi was relatively small.The maximum risk probability(Pmax)of the population under external environmental interference was 0.07％,indicating that the growth trend of the population was not obvious when it was disturbed by external random interference.To effectively protect Rh.griersonianum,it is advisable to protect the population in situ,improve the survival of seedlings and small trees,and facilitate natural regeneration and recovery of the population.
Rhododendron griersonianumpopulation age structurestatic life tablesurvival curvedynamic analysis
万方数据
维普
