TY  - EJOU
AU  - Liao, Manzhu 
AU  - Yang, Lan 
AU  - Tie, Liehua 
AU  - Guo, Qiqiang 
AU  - Zheng, Weilie 
AU  - Li, Jiangrong 
AU  - Li, Yongxia 

TI  - Survival Status and Trend Prediction of the Endangered Plant <i>Cupressus gigantea</i> Populations in Tibet Plateau
T2  - Phyton-International Journal of Experimental Botany

PY  - 2025
VL  - 94
IS  - 11
SN  - 1851-5657

AB  - <i>Cupressus gigantea</i> is an endemic endangered tree species in the Tibet Plateau, and studying the survival status of the different <i>C. gigantea</i> populations and revealing the main environmental factors that affect the population survival are particularly significant for the conservation and sustainable development of endangered species. Based on the 28 sample plots, the Hierarchical Cluster Method was used to classify the <i>C. gigantea</i> populations into four community types. Age structure diagrams were drawn based on the structure of each community, static life tables and survival curves were compiled, and the future development trends of each age group in each population were predicted. Additionally, principal component analysis was used to preliminarily explore the mutual relationship between <i>C. gigantea</i> populations and the environment. The results indicated that <i>C. gigantea</i> is the primary dominant species in the four populations, and their survival curves generally conform to the Deevey-III. This is characterized by high mortality rates among the young and middle-aged individuals, as well as the insufficient replenishment of young individuals, and a severe shortage of elderly individuals. Specifically, generational gaps frequently occur within populations. As time goes on, ageing will become increasingly severe. Furthermore, soil organic matter, thickness, and moisture contents, and altitude significantly influence the growth and expansion of <i>C. gigantea</i> populations. This study suggests that timely replanting and transplanting of young trees should be carried out for Population A, while management and protection of Populations B and C should be strengthened to prevent further decline of middle-aged and older individuals. Appropriate transplantation should be conducted for individuals of Population D growing at extremely high and low altitudes. Additionally, protection of <i>C. gigantea</i> individuals (especially juvenile-stage individuals) and their native habitats should be strengthened. Research on germplasm resources and cultivation management techniques should be intensified to enhance the stress tolerance of <i>C. gigantea</i>, thereby alleviating the generational gap phenomenon across all populations, and to promote population renewal and expansion.
KW  - Age structure; life tables; survival curves; environmental factors; time series

DO  - 10.32604/phyton.2025.072725