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通过调查把朗乡林区的森林划分成17个林型。朗乡林区原生主要林型中主要树种的重要值随海拔高度明显的变化规律。红松的重要值在海拔300—500m间最大,海拔高超过500m红松重要值急剧下降。山地杨桦林中天然更新的红松重要值也以300—500m间最大。 文中采用的重要值求算公式为: 重要值=相对密度[D_(1.3)≥5cm的林木)(％)+相对频度[D_(1.3)<5cm的有效更新频度](％)+相对优势度[D_(1.3)≥5cm的林木](％) 把杨桦林恢复成阔叶红松林的途径,可采取逐步间伐杨桦林并一次更新红松的办法加以完成。 此途径适用山地杨桦林,具体林分特徒及立地条件参阅正文表2、用于海拔300—600m对杨桦林进行株数、强度10—20％的多次间伐,间隔期10年,初次间伐后植入红松1000株/ha,成活率要求90％以上,最终予期红松、云冷杉、硬阔的重要值各占1/3左右,近似于原始阔叶红松林的重要值组成。 上述(?)径从实施到完成约30年、林分质量和恢复速度优于同期间的自然演替林分。
Through the investigation, the forest in Longxiang forest area is divided into 17 forest types. The significant values of the major tree species in the native primary forest types in Longxiang forest area vary obviously with altitude. The important value of Korean pine is 300-500m above sea level, and the value of Korean pine is decreasing sharply when the altitude is over 500m. Natural regeneration of birch in mountain birch important value of 300-500m also between the largest. The important value used in this paper is: The importance value = the relative density [D 1.3 (≥ 1.3) ≥5 cm) (%) + relative frequency [D 1.3 (effective update frequency of <5cm] Dominance [D 1.3 (≥ 1.3) ≥5 cm] (%) The restoration of birch to broad-leaved Korean pine forest can be accomplished through the stepwise thinning of birch and the regeneration of Korean pine. This approach is suitable for mountain birch forests, specific stand points and site conditions refer to the text in Table 2, for elevation 300-600m on the number of birch, the intensity of 10-20% of the multiple thinning interval of 10 years after the first thinning implantation 1000 / ha of Pinus koraiensis / ha, the survival rate of more than 90%, the final expected Korean pine, fir spruce, hard broad important value of about 1/3, similar to the original broad-leaved korean pine important value composition. The above (?) Path from implementation to completion of about 30 years, stand quality and recovery rate is better than the same period of natural succession stand.