Characteristics of height-diameter ratio of average trees and dominant trees in artificial Chinese fir stand

To reveal The characteristics of height-diameter ratio of average trees to dominant trees in artificial Chinese fir stands and its relationship with competitive pressure, and to provide scientific basis for expanding the application of height-diameter ratio in forest management.

The survey data and stem analysis data of average and dominant trees of 98 plots at different ages stages, initial planting density and status index of the same age pure forest of artificial Chinese fir in Jian’ou City, Youxi County and Wuping County of Fujian Province were selected. Wilcoxon signed rank test was used to analyze the difference of height-diameter ratio between average and dominant trees in paired stands at different age stages, initial planting density and status index. Kruskal-Wallis test was used to analyze the difference of height-diameter ratio, DBH and tree height when only a certain stand factor (age stage or initial planting density or status index) changed. The difference of height-diameter ratio between average trees and dominant trees in the detailed sample plot (average trees minus dominant trees) is greater than 0, and the maximum, minimum and average values of the difference are 41.9, 1.0 and 13.1 respectively.

The paired contrast of height-diameter ratio of the average and dominant trees in the detailed survey plot is extremely significant, and the paired contrast of height-diameter ratio of the average and dominant trees in different age stages, initial planting density and status index is extremely significant. When only the age stage or initial planting density or status index changes, there is no significant difference in the height-diameter ratio between the average trees and dominant trees in the plot, but there are significant or extremely significant differences in the DBH of the average trees and dominant trees in the plot. When only the age stage or status index changes, there are significant or extremely significant differences in the tree height of the average trees and dominant trees in the plot.

There is a significant difference between the height-diameter ratio of the average tree and the dominant tree in the detailed survey sample of artificial Chinese fir forest, and the height-diameter ratio of the average tree is greater than that of the dominant tree. The height-diameter ratio of average trees to dominant trees in detailed plots is less affected by age stage, initial planting density and status index. The DBH of the average and dominant trees in the detailed sample plot is greatly influenced by age stage, initial planting density and status index. The average tree height and dominant tree height in the detailed sample plot are greatly influenced by age stage and status index. The height-diameter ratio can be used as an index to characterize the competitive pressure of pure plantations of Chinese fir of the same age and is not affected by stand factors such as age, initial planting density and site quality.