呼中林区与呼中自然保护区森林粗木质残体储量的比较

 采用样线法研究了人为干扰对大兴安岭呼中林区粗木质残体(Coarse woody debris, CWD)储量的影响。结果表明, 未受人为干扰的呼中自然保护区中CWD变化范围集中在5.92~43.53 m³·hm^–2, 受到人为干扰的呼中林区中CWD变化范围集中在12.70~47.59 m³·hm^–2之间。人为干扰对混交林和针叶林的CWD储量影响显著, 而对阔叶林CWD储量影响不显著。人为干扰增加了混交林CWD储量, 减少了针叶林CWD储量, 同时减少了枯立木的数量, 增加了高度腐烂的CWD的比例。对兴安落叶松各林型的分析表明, 人为干扰条件下CWD储量(8.20~25.60 m³·hm^–2)是未受干扰条件下CWD储量(18.70~36.99 m³·hm^–2)的1/4~1/3。为促使采伐后的森林能维持原始林粗木质残体的结构特征, 建议保留采伐剩余物以维持一定储量的CWD。

COMPARISON OF STORAGE OF COARSE WOODY DEBRIS BETWEEN HUZHONG FOREST BUREAU AND HUZHONG NATURAL RESERVE IN DA HINGGAN MOUNTAINS, CHINA

Aims Coarse woody debris (CWD) plays an important role in maintaining biodiversity, providing critical habitat for organisms and cycling of carbon and nitrogen in forest systems. Our objective was to understand the effects of anthropogenic disturbance on CWD in Da Hinggan Mountains as the key to forest health and sustainable forest management.Methods We compared CWD storage using a line-intercept method in Huzhong Forest Bureau, which represented forest affected by anthropogenic disturbance, with Huzhong Natural Reserve, which represented primary forest unaffected by anthropogenic disturbance, of Da Hinggan Mountains. Important findings Storage of CWD varied between 5.92-43.53 m~3·hm~(-2) in Huzhong Natural Reserve and 12.70-47.59 m~3·hm~(-2) in Huzhong Forest Bureau. Anthropogenic disturbance had greater effects on mixed and coniferous forest than broadleaf forest. More CWD occurred in mixed forest and less CWD in coniferous forest, and the proportion of the advanced decay class CWD increased and snags decreased with anthropogenic disturbance. The storage of CWD in managed forest (8.20-25.60 m~3·hm~(-2)) is less than that in virgin forest (18.70-36.99 m~3·hm~(-2)). Residue from harvesting should be maintained to retain the natural forest characteristics of CWD.