Abstract:

The study used a combination of literature collection and field plant investigation to conduct a systematic of and study ancient Ficus microcarpa resources in Hainan Province.The resource status,distribution pattern,and growth characteristics of ancient F.microcarpa were analyzed,and a tree age-height model was constructed to reveal the senescence mechanism of ancient F.microcarpa in Hainan,and to provide theoretical and practical basis for the daily maintenance management and rejuvenation of ancient F.microcarpa.The results showed that a total of 3 715 ancient F.microcarpa were recorded in Hainan Province,distributed in cluster.Haikou City and Lingao County had a higher distribution of trees,accounting for 48.7% of the total number of trees;the countryside is the main distribution area of Hainan ancient F.microcarpa,accounting for 92.84% of the total number of trees.Most of the ancient F.microcarpa also had good growth status and site conditions,and their age,diameter at breast height and height structure are normally distributed,and a logistic model equation of y=1.369/(1+7.053e^-2.852x)(R²=0.998) was fitted to represent the relationship between age and height of ancient Ficus microcarpa.The results of leaf physiological tests showed that the chlorophyll content and SOD enzyme activity of the normal plant of ancient F.microcarpa were higher than those of the weakened plant,but the MDA content was lower than that of the weakened plant,indicating that the chlorophyll content,SOD enzyme activity and MDA content of the plant can be used as one of the physiological indicators to determine the senescence of ancient trees.

Key words: Hainan Province, ancient Ficus microcarpa, resource characteristics, growth characteristics, physiological index