Chin J Plan Ecolo ›› 2004, Vol. 28 ›› Issue (2): 252-257.DOI: 10.17521/cjpe.2004.0037

• Research Articles • Previous Articles     Next Articles

STUDY ON NUMERIC DYNAMICS OF NATURAL POPULATIONS OF THE ENDANGERED SPECIES DISANTHUS CERCIDIFOLIUS VAR. LONGIPES

XIAO Yi-An, HE Ping, LI Xiao-Hong, DENG Hong-Ping   

  • Published:2004-02-10
  • Contact: XIAO Yi-An

Abstract:

Disanthus cercidifolius var. longipes is an endangered plant species which is only distributed in Jinggang Mountain, Junfeng Mountain and Guanshan, Jiangxi Province,Longquan, Zhejiang Province, and Mangshan, Hunan Province, China. At present, its population is small and decreasing. In order to better understand its decline, we studied the population dynamics of this species using static life tables, fecundity schedules, Leslie matrices and time sequence analysis based on an in-depth investigation of age structure, seed production and seed germination rate. The results are as follows: Net reproductive rate (R0), intrinsic rate of increase (rm) and finite ratio fineries (λ) are 0.833 7, -0.004 7 and 0.995 3, respectively. Values of the separameters (R0<1, rm<0, λ<1) indicated that the population is decreasing. The Leslie matrix model predicted that over the next 50 years the number of populations would decrease from 227 1 to 764, i.e., only 30% will remain. The results of the time sequence analysis agreed with the Leslie matirix model prediction. The key threats to this species are most likely deforestation and habitat fragmentation.