Dong Ling-Bo, Tian Dong-Yuan, Chen Ying, Liu Zhao-Gang
Ministry of Education Key Laboratory of Sustainable Forest Ecosystem Management, School of Forestry, Northeast Forestry University, Harbin 150040, China.
Ying Yong Sheng Tai Xue Bao. 2021 Aug;32(8):2763-2772. doi: 10.13287/j.1001-9332.202108.010.
Based on data from 49 plots of natural forests in Cuigang Forest Farm of Xinlin Forestry Bureau, Daxing'anling Mountains, China, we used 37 measurable variables that mainly focused on stand non-spatial structure, stand spatial structure, species diversity, soil condition, and site condition to construct the structural equation model of natural regeneration densities and size diversities (., height and ground-diameter). The direct, indirect, and total influence coefficients of each path were quantified to extract the critical and controllable factors that influence regeneration density and diversity of natural forests, which would help implement sustainable forest management. The results showed that the effects of various latent variables on rege-neration density were following an order as: stand non-spatial structure (-0.410) > species diversity (0.380) > soil condition (0.250) > site condition (0.249) > stand spatial structure (0.197), while the order were changed as: soil condition (0.778) > site condition (0.748) > stand spatial structure (0.684) > stand non-spatial structure (0.287) > forest diversity (0.105), when evaluated on the regeneration diversity. Generally, the critical and controllable factors affecting rege-neration quantity and diversity were soil pH, total potassium concentration, species diversity, tree height diversity, uniform angle index and stand volume per hectare. In the management, suitable thinning treatments or replanting broadleaved trees were recommended for optimizing and adjusting species composition, species diversity, soil pH and nutrition, which would promote natural regene-ration.
基于中国大兴安岭新林林业局翠岗林场49块天然林样地的数据，我们使用了37个可测量变量，这些变量主要集中在林分非空间结构、林分空间结构、物种多样性、土壤条件和立地条件上，以构建天然更新密度和大小多样性（即树高和地径）的结构方程模型。对各路径的直接、间接和总影响系数进行量化，以提取影响天然林更新密度和多样性的关键和可控因素，这将有助于实施森林可持续经营。结果表明，各潜在变量对更新密度的影响顺序为：林分非空间结构（-0.410）＞物种多样性（0.380）＞土壤条件（0.250）＞立地条件（0.249）＞林分空间结构（0.197），而在评估更新多样性时，顺序变为：土壤条件（0.778）＞立地条件（0.748）＞林分空间结构（0.684）＞林分非空间结构（0.287）＞森林多样性（0.105）。一般来说，影响更新数量和多样性的关键和可控因素是土壤pH值、全钾含量、物种多样性、树高多样性、均匀角指数和每公顷林分蓄积量。在经营管理中，建议进行适当的间伐处理或补植阔叶树，以优化和调整物种组成、物种多样性、土壤pH值和养分，从而促进天然更新。
