›› 1981, Vol. 17 ›› Issue (4): 419-425.
• 论文及研究报告 •
Abstract: Growth and differentiation of the dominant trees(classes Ⅰ,Ⅱ,and Ⅲ) on the one hand and decline and death of the suppressed trees(classes Ⅳ and Ⅴ) on the other hand are two inseparable phases in the process of natural thinning in the stands of Pinus yunnanensis. In other than fully stocked stands,there are fewer dominant trees reduced to suppressed ones and also fewer suppressed trees becoming dead ones.As a result,the current annual increment of the stand basal area gradually increases.When the cumulative basal area of the dominant trees in a stand is close upon P=0.7 or that of the entire stand approaches its maximum value (P=1.0),the growth of the stand then reaches a level characteristic of a fully stocked stand. The decrease in the number of dominant trees in a stand occurring simultaneously with the decrease in the number of trees of the entire stand varies mainly with stand density,which is in fact an outcome of the intera ction of such factors as stand site quality,age and density.For stands with approximately equal average ages,the relationship between the number of dominant trees and the total number of trees may be expressed by the curve of a power function.Accordingly the number of dominant trees that should be retained in tending felling for stands of Pinus yunnanensis may be estimated with considerable accuracy.
杨永祥. 云南松林分自然稀疏规律的研究[J]. , 1981, 17(4): 419-425.
Yang Yong-xiang. A STUDY OF THE LAWS OF NATURAL THINNING IN STANDS OF Pinus yunnanensis[J]. , 1981, 17(4): 419-425.
导出引用管理器 EndNote|Reference Manager|ProCite|BibTeX|RefWorks