Long-term effects of planting density and site quality on timber assortment structure based on a 41-year plantation trial of Chinese fir
Stand density control coupled with site control is a key technique for cultivating large-diameter timber of Chinese fir trees, whose yield can be effectively increased by the optimal density and site management mode employed. This study aimed to evaluate the dynamic changes in timber assortment stru...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2023-06-01
|
| Series: | Trees, Forests and People |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2666719323000286 |
| _version_ | 1827922496325681152 |
|---|---|
| author | Xiaoyan Li Aiguo Duan Jianguo Zhang |
| author_facet | Xiaoyan Li Aiguo Duan Jianguo Zhang |
| author_sort | Xiaoyan Li |
| collection | DOAJ |
| description | Stand density control coupled with site control is a key technique for cultivating large-diameter timber of Chinese fir trees, whose yield can be effectively increased by the optimal density and site management mode employed. This study aimed to evaluate the dynamic changes in timber assortment structure under differing initial planting densities and site quality based on growth data of a 41-year trial of Chinese fir plantations. Our results showed that the total timber yield and both large-diameter timber outturn and the outturn rate all increased with better site quality under the same initial planting density. Further, the outturn peak as well as outturn rate peak for both medium- and small-diameter timber was reached sooner with improved site quality. For the same site class, a lower initial planting density augmented the total timber outturn rate, and also resulted in less time required for the total timber outturn rate to reach a constant or maximum value. Finally, the total timber outturn rate of all density plots tended to be nearly identical. Using a high planting density increased the outturn of small-diameter timber, whose outturn peak was delayed in the denser plots. The bolstering effect of low density upon the growth of large-diameter timber was enhanced by higher site quality, with density-induced differences in large-diameter timber more pronounced; conversely, that promoting effect weakened under poor site quality conditions. The interaction between planting density and site index significantly influenced the growth of any timber assortment of Chinese fir in the early stage following its formation. Notably, the significant effect of site index on large-diameter timber lasted longer than that of other timber assortments. The optimal site conditions for cultivating large-diameter timber trees of Chinese fir consist of a site class ≥ 20 with a planting density limited to no more than 1667 trees/ha, whose stand rotation period must be over 26 years, so as to maximize the output of large-diameter timber yield. Our empirical findings will be helpful for the construction of an optimal cultivation mode for the density, site, and rotation age of large-diameter timber in Chinese fir plantations. |
| first_indexed | 2024-03-13T04:43:32Z |
| format | Article |
| id | doaj.art-90caf32193e1485fa7682d9a589178f9 |
| institution | Directory Open Access Journal |
| issn | 2666-7193 |
| language | English |
| last_indexed | 2024-03-13T04:43:32Z |
| publishDate | 2023-06-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Trees, Forests and People |
| spelling | doaj.art-90caf32193e1485fa7682d9a589178f92023-06-19T04:29:50ZengElsevierTrees, Forests and People2666-71932023-06-0112100396Long-term effects of planting density and site quality on timber assortment structure based on a 41-year plantation trial of Chinese firXiaoyan Li0Aiguo Duan1Jianguo Zhang2State Key Laboratory of Efficient Production of Forest Resources, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, People's Republic of ChinaState Key Laboratory of Efficient Production of Forest Resources, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, People's Republic of China; Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, People's Republic of China; Corresponding author at: State Key Laboratory of Efficient Production of Forest Resources, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, People's Republic of China.State Key Laboratory of Efficient Production of Forest Resources, Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, People's Republic of China; Collaborative Innovation Center of Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, People's Republic of ChinaStand density control coupled with site control is a key technique for cultivating large-diameter timber of Chinese fir trees, whose yield can be effectively increased by the optimal density and site management mode employed. This study aimed to evaluate the dynamic changes in timber assortment structure under differing initial planting densities and site quality based on growth data of a 41-year trial of Chinese fir plantations. Our results showed that the total timber yield and both large-diameter timber outturn and the outturn rate all increased with better site quality under the same initial planting density. Further, the outturn peak as well as outturn rate peak for both medium- and small-diameter timber was reached sooner with improved site quality. For the same site class, a lower initial planting density augmented the total timber outturn rate, and also resulted in less time required for the total timber outturn rate to reach a constant or maximum value. Finally, the total timber outturn rate of all density plots tended to be nearly identical. Using a high planting density increased the outturn of small-diameter timber, whose outturn peak was delayed in the denser plots. The bolstering effect of low density upon the growth of large-diameter timber was enhanced by higher site quality, with density-induced differences in large-diameter timber more pronounced; conversely, that promoting effect weakened under poor site quality conditions. The interaction between planting density and site index significantly influenced the growth of any timber assortment of Chinese fir in the early stage following its formation. Notably, the significant effect of site index on large-diameter timber lasted longer than that of other timber assortments. The optimal site conditions for cultivating large-diameter timber trees of Chinese fir consist of a site class ≥ 20 with a planting density limited to no more than 1667 trees/ha, whose stand rotation period must be over 26 years, so as to maximize the output of large-diameter timber yield. Our empirical findings will be helpful for the construction of an optimal cultivation mode for the density, site, and rotation age of large-diameter timber in Chinese fir plantations.http://www.sciencedirect.com/science/article/pii/S2666719323000286Chinese firInitial planting densityLarge-diameter timberSite indexTimber assortment structure |
| spellingShingle | Xiaoyan Li Aiguo Duan Jianguo Zhang Long-term effects of planting density and site quality on timber assortment structure based on a 41-year plantation trial of Chinese fir Trees, Forests and People Chinese fir Initial planting density Large-diameter timber Site index Timber assortment structure |
| title | Long-term effects of planting density and site quality on timber assortment structure based on a 41-year plantation trial of Chinese fir |
| title_full | Long-term effects of planting density and site quality on timber assortment structure based on a 41-year plantation trial of Chinese fir |
| title_fullStr | Long-term effects of planting density and site quality on timber assortment structure based on a 41-year plantation trial of Chinese fir |
| title_full_unstemmed | Long-term effects of planting density and site quality on timber assortment structure based on a 41-year plantation trial of Chinese fir |
| title_short | Long-term effects of planting density and site quality on timber assortment structure based on a 41-year plantation trial of Chinese fir |
| title_sort | long term effects of planting density and site quality on timber assortment structure based on a 41 year plantation trial of chinese fir |
| topic | Chinese fir Initial planting density Large-diameter timber Site index Timber assortment structure |
| url | http://www.sciencedirect.com/science/article/pii/S2666719323000286 |
| work_keys_str_mv | AT xiaoyanli longtermeffectsofplantingdensityandsitequalityontimberassortmentstructurebasedona41yearplantationtrialofchinesefir AT aiguoduan longtermeffectsofplantingdensityandsitequalityontimberassortmentstructurebasedona41yearplantationtrialofchinesefir AT jianguozhang longtermeffectsofplantingdensityandsitequalityontimberassortmentstructurebasedona41yearplantationtrialofchinesefir |