Cheng Fushan, Zhao Xun, Luo Ye, Tian Jiaxin, Sun Yue, Wang Hongbo, Wang Qingyu, Zhu Jiaheng, Yang Cancan, He Huaijiang, Liu Guoliang
College of Forestry, Beijing Forestry University, Beijing, 100083, China.
Jilin Provincial Academy of Forestry Sciences, Changchun, 130117, China; Jilin Province Degraded Forest Ecosystem Restoration and Reconstruction Interregional Cooperation Science and Technology Innovation Center, Changchun, 130117, China.
J Environ Manage. 2025 Jun;385:125707. doi: 10.1016/j.jenvman.2025.125707. Epub 2025 May 8.
Understanding the mechanisms whereby harvesting disturbance influences canopy structural complexity, forest productivity, and the stability of productivity is essential for the effective management and conservation of natural secondary forests. Previous research has established significant positive correlations among biodiversity, forest productivity and stability. Nevertheless, less is known regarding the processes whereby stand and canopy structures influence forest productivity and stability following harvesting disturbance. Because LiDAR systems are superior in acquiring information on forest canopy structure. In this study, we investigated the relationships among canopy structure, productivity, and stability of mixed conifer-broadleaf forest at 11 years post-thinning (2011-2022) (thinning intensity: int1 = 0 %, 0 %< int2 ≤20 %, 20 %< int3 ≤40 %, 40 %< int4 ≤60 %, int5 >60 %), utilizing field plot and LiDAR data. We quantified forest canopy structural complexity by calculating canopy entropy based on spatial point-cloud patterns. The results indicated that increasing thinning intensity significantly reduced canopy structural complexity and forest productivity (p < 0.05). However, the difference was not significant at thinning intensity less than 40 %. The structural equation model revealed that the indirect effects of thinning on forest productivity and stability, mediated through changes in density, forest height structural, dominant tree DBH, and canopy structural complexity, are greater than the direct effects. Moreover, density, dominant trees DBH, forest height structural, and canopy structural complexity are key drivers of forest productivity and stability. These findings elucidate the relationships among canopy structure, forest ecosystem productivity, and stability, and highlight the effects of thinning disturbance on these relationships. These insights will facilitate a deeper understanding of the interactions between structure and function in complex ecosystems and contribute to sustainable forest management.
了解采伐干扰影响林冠结构复杂性、森林生产力以及生产力稳定性的机制，对于天然次生林的有效管理和保护至关重要。先前的研究已经证实生物多样性、森林生产力和稳定性之间存在显著的正相关关系。然而，对于采伐干扰后林分和林冠结构影响森林生产力和稳定性的过程，我们了解得较少。由于激光雷达系统在获取森林冠层结构信息方面具有优势。在本研究中，我们利用样地和激光雷达数据，调查了间伐11年后（2011 - 2022年）针叶 - 阔叶混交林的林冠结构、生产力和稳定性之间的关系（间伐强度：int1 = 0%，0% < int2 ≤ 20%，20% < int3 ≤ 40%，40% < int4 ≤ 60%，int5 > 60%）。我们基于空间点云模式计算冠层熵来量化森林冠层结构复杂性。结果表明，间伐强度的增加显著降低了冠层结构复杂性和森林生产力（p < 0.05）。然而，在间伐强度小于40%时，差异不显著。结构方程模型表明，间伐通过密度、林分高度结构、优势木胸径和冠层结构复杂性的变化对森林生产力和稳定性产生的间接影响大于直接影响。此外，密度、优势木胸径、林分高度结构和冠层结构复杂性是森林生产力和稳定性的关键驱动因素。这些发现阐明了冠层结构、森林生态系统生产力和稳定性之间的关系，并突出了间伐干扰对这些关系的影响。这些见解将有助于更深入地理解复杂生态系统中结构与功能之间的相互作用，并为可持续森林管理做出贡献。
