Influence of planting density and thinning on timber productivity and resistance to wind damage in Japanese larch (Larix kaempferi) forests
Influence of planting density and thinning on timber productivity and resistance to wind damage in Japanese larch (Larix kaempferi) forests
复制标题
种植密度和间伐对日本落叶松林木材生产力和抗风害能力的影响
DOI：
10.1016/j.jenvman.2020.110298
复制
发表时间：
2020
影响因子：
8.7
通讯作者：
Masaka Kazuhiko
中科院分区：
文献类型：
--
作者：
Torita Hiroyuki ;Masaka Kazuhiko
近年来，日本北部的北海道频繁发生台风造成的森林破坏。根据预测报告，台风的强度会增加，然后在向北移动时保持强度。这种预测与森林破坏之间的关系尚不清楚，但处理森林破坏的重要性日益增加。为此，本文以日本北部主要造林树种日本落叶松（Larix kaempferi）为研究对象，评价了不同种植密度和间伐对其木材产量和抗风害能力的影响。本文研究了3种管理类型：稀疏（ST：相对产量指数< 0.8）、中等（MT：相对产量指数< 0.9）和密集（DT：未疏化）。为了评估对风害的抵抗力，使用机械模型计算了倾覆和折断树干所需的临界风速。此外，利用产量预测系统估算了林龄为10-50年的木材量。管理类型和种植密度（1500 ~ 2500株/ m2）影响抗风害能力。可承受低种植密度（1500株/ ha−1），具有较高的抗逆性。相比之下，根据50年林龄的立地指数（SI= 22、25和28），不同情景下的总木材量在440到630立方米之间变化。根据管理类型、种植密度和si的不同，最终采伐的可销售原木体积约为210至470立方米。原木体积与抗风害能力呈负线性相关。因此，平衡降低风害风险和提高木材产量或优先考虑它们是很重要的。
In recent years, forest damage caused by typhoons has occurred frequently in Hokkaido, northern Japan. According to predictive reports, a typhoon's intensity increases and it then maintains its intensity as it moves north. The relationship between this prediction and forest damage is not clear, but the importance of dealing with forest damage is increasing. Therefore, to consider the countermeasures in forest management, we evaluated the influence of planting density and thinning on timber yield and resistance to wind damage in Japanese larch (Larix kaempferi), which is one of the main tree species used for afforestation in northern Japan. In this study, the following three management types were investigated: sparse (ST: relative yield index < 0.8), middle (MT: relative yield index < 0.9), and dense (DT: unthinned). To assess resistance to wind damage, the critical wind speed required to overturn and break the trunks of trees was calculated using a mechanistic model. Furthermore, timber volumes were estimated from a stand age of 10–50 years using the Yield Prediction System. The management type and planting density (1500–2500 trees ha−1) affected resistance to wind damage. Scenarios withSTand low planting density (1500 trees ha−1) showed a high resistance. In contrast, total timber volumes for scenarios varied from approximately 440 to 630 m3depending on the site index (SI= 22, 25, and 28) at a stand age of 50 years. The merchantable log volume of the final cutting varied from approximately 210 to 470 m3depending on the management type, planting density, andSI. There was a negative linear correlation between the log volume and resistance to wind damage. Therefore, it is important to balance both the decreased wind damage risk and higher timber yield or to prioritize them.