Spatial Structure and Three-dimensional Green Quantity of Cratoxylum cochinchinense Population

Three plots of Cratoxylum cochinchinense were set up in the Pearl River Delta of South China. The species structure characteristics and three-dimensional green quantity distribution of C. cochinchinense were analyzed by means of sample plots method. The results showed that the vast majority of C. cochinchinense have not entered the age of physiological aging in the sample plots, and they were growth-type populations in Tea-mountain and Baiyun-mountain sample plots, while it was stable-type in Shihua-mountain. There were significant differences in the preservation density, frequency and coverage of C. cochinchinense population. The height increases with population age but there is exception-Abnormal growth of height and crown width in Shihua-mountain under environmental impact. The total green contribution was 14 431.484 m³. The amount of contribution order for green was Tea-mountain > Baiyun-mountain > Shihua-mountain. The high green amount was mainly distributed in the middle stage, but the contribution of the young and old stage was low. It was significant positive correlation between three-dimensional green quantity and DBH of single tree,and the functional model as follows: G_q = 0.212x^2.285.