西南林业大学学报2017，Vol.37Issue(5)：1-8,8.DOI:10.11929/j.issn.2095-1914.2017.05.001
VDT法疏伐云南松人工林胸径及其断面积结构的动态变化研究
Structural Dynamic Changes of the Diameter at Breast Height and Basal Area in a VID Thinned Pinus yunnanensis Plantation
摘要
Abstract
In order to understand the dynamic effects of thinned Pinus yunnanensis plantation on diameter at breast height (DBH) and their basal area (BA) structures for being thinned at middle aged stage (25-year-old), the method of variable-density thinning ( VDT ) was employed to be thinned 4 sampling plots ( SPs ) of P. yunnanensis plantation with densities of 7311, 3660, 4612, and 3045 stem/hm2 of the species, respectively, which never implemented any tending approaches after established stand by seeding method at Xujiashan Forest Zone in Lufengcun Forestry Centre, Yiliang County, Kunming. The thinning intensities were 0. 0% ( ck) , 25. 8%, 31. 5% and 27. 7% for abovementioned SPs. Dynamic changes of DBH, BA and their important value (IV) of stand trees were analyzed based on 2 cm acted as one DBH grade for the period of before stand thinned, after mo-ment and for 5 years thinned. The results showed that the 6 and 8 cm were dominant DBH grade of standing-stocks, however, the 6-12 cm grade was dominaant BA with 77. 5%, 70. 4%, 74. 6% and 72. 1% of total BA for the 4 SPs, respectively, before stand thinned. After the forest thinned, excepting the proportion varied, the 6-12 cm grade structured primary the BA ( which were 73. 9%, 73. 7%, and 69. 3%of total Bas for the SP 2-4, respective-ly) also. After thinned for 5 years, stand trees composed of the BA was forward to 8-14 cm DBH grade, and there were great proportion increment of the 12 and 14 grade trees with 23. 5%, 21. 5%, 24. 4%and 32. 8%of those two DBH grade in total stand trees, respectively. Moreover, the total BA of the SP 2-4 were from 13. 86, 28. 31 and 24. 24 m2/hm2 after thinned moment increased to 24. 02, 36. 43 and 26. 33 m2/hm2 after 5 years thinned, while which of natural thinning SP 1 was from 39. 21, 26. 33 m2 decreased to 29. 07, 26. 33 m2 at the same period with the SP 2-4. Simultaneously, the total BA of the SP 2-4 increased by 73. 3%, 28. 7% and 8. 5% respectively after thinning, the control stand ( SP 1) decreased by 25. 8%. Stand tree IVs of dominant structures also moved forward to bigger DBH grade orientation with tree growth after stand thinned.关键词
云南松/人工林/可变密度疏伐/胸径/断面积/动态变化Key words
Pinus yunnanensis/plantation/variable-density thinning/diameter at breast height/basal area/dynamics分类
农业科技引用本文复制引用
李莲芳,王慷林,段安安,李卫冲,郑树宏,龚建斌..VDT法疏伐云南松人工林胸径及其断面积结构的动态变化研究[J].西南林业大学学报,2017,37(5):1-8,8.基金项目
国家自然科学基金项目 (31170585) 资助 （31170585）
林业科学技术推广项目 ([2015] 26号) 资助 （[2015] 26号）
云南省十一五科技攻关及高新技术发展计划 (2006NG 29) 资助. （2006NG 29）
