Chin J Plan Ecolo ›› 2008, Vol. 32 ›› Issue (2): 448-455.DOI: 10.3773/j.issn.1005-264x.2008.02.024

• Research Articles • Previous Articles     Next Articles

INFLUENCES OF SUBSTITUTING SIZE VARIABLES FOR AGE ON POPULATION SURVIVAL ANALYSIS: A CASE STUDY OF PINUS TABULAEFORMIS AND P. ARMANDII IN QINLING MOUNTAIN, CHINA

HE Ya-Ping1; FEI Shi-Min1; JIANG Jun-Ming1; CHEN Xiu-Ming1; ZHANG Xu-Dong2; HE Fei1   

  1. 1Sichuan Academy of Forestry, Chengdu 610081, China; 2 Chinese Academy of Forestry, Beijing 100091, China
  • Online:2008-03-30 Published:2008-03-30
  • Contact: FEI Shi-Min

Abstract: Aims Our objectives were to 1) explore the feasibility of using individual height and basal diameter as substitutes for age, and 2) determine the influence of using these parameters on survival curve analysis for Pinus armandii and P. tabulaeformis populations in an area damaged by water disaster in the northern Qinling Mountain. 
Methods We investigated two dominant species, P. tabulaeformis and P. armandii, which had regenerated after damage by water disaster 17 years earlier. We measured height, basal diameter and age of two species in 6 plots (total plot area was 11 900 m2). We determined age by counting number of whorls of branches.
Important findings It was infeasible to use basal diameter and tree height in place of age for P. armandii because the relationship to age was an exponential function for both parameters; therefore, we used logarithmic values for basal diameter and tree height. In contrast, the functions were linear for P. tabulaeformis. The survival curves were all linear type with no type differences between base diameter, tree height and factual age. Our study indicates that it is feasible to use basal diameter and tree height as indices for factual age when the relationships of basal diameter and tree height to age are linear. Investigation of relations of age and size and their influential factors is important for the analysis of plant population demography.