北京林业大学学报2016，Vol.38Issue(6)：17-27,11.DOI:10.13332/j.1000--1522.20150458
小兴安岭凉水典型阔叶红松林林冠干扰特征分析
Characteristics of canopy disturbance for a typical broadleaf-Korean pine mixed forest in Xiaoxing’ an Mountains, Liangshui, northeastern China
摘要
Abstract
To analyze the characteristics and formation causes of expanded gaps due to canopy disturbance in a broadleaf-Korean pine ( Pinus koraiensis ) mixed forest in Xiaoxing ’ an Mountains, Liangshui, northeastern China, we investigated all expanded gaps (≥50 m2 ) in a 6 ha permanent plot by using the quadrat survey and dendrochronology methods. Results showed that the expanded gaps, with a speed of 0. 08 ha per year, occurred by an average density of 7. 67 gaps per hectare. The frequency and return period of canopy disturbance was 0. 42% per year and 240 years, respectively. The main formative tree species of forest gaps were P. koraiensis (50. 2%) , A. nephrolepis (9. 78%) , Betula costata (7. 78%) and other trees (10. 44%) which cannot be identified to species level due to serious decay. Death modes of trees for a gap were mainly breakage at trunk base ( BB, 54. 89%) . Forest gaps were formed mainly by more than three ways of tree death, which accounted for 70. 83% of all gaps. The average number of gap makers in a gap was 9. 38 individuals, and most of them were in a higher decay level. Small-diameter fallen trees were often the victims rather than makers of gap formation, and the contribution of <br> conifers to a gap formation was much greater than broadleaf trees. The average diameter at breast height in a gap border was 46. 68 cm ( range 11. 4--126. 5 cm ) and height of trees 23. 6 m ( range 5. 6--42. 9 m) , and the major tree species was Pinus koraiensis (63. 08%) . Abies nephrolepis grew fastest among all tree species in gap borders, while Picea koraiensis and Acer mono grew slowest. The species and compositions of gap makers and border trees were similar in gaps of different sizes, but the definition standard of gap makers has significant influences on the causes of gap formation. The accuracy of reconstruction of disturbance history and determination of formation causes can be greatly improved by surveying large and medium-sized gaps as well as large diameter makers using several comprehensive methods. In addition, the development and formation process of large and medium-sized gaps in which two or more disturbances occurred can be clarified, which is crucial for understanding the dynamics of canopy disturbance and succession of forest communities.关键词
林窗/林冠干扰/树木年轮/阔叶红松林/小兴安岭Key words
forest gap/canopy disturbance/tree rings/the broadleaf-Korean pine forest/Xiaoxing’ an Mountains分类
农业科技引用本文复制引用
朱良军,金光泽,杜文先,王晓春..小兴安岭凉水典型阔叶红松林林冠干扰特征分析[J].北京林业大学学报,2016,38(6):17-27,11.基金项目
中央高校基本科研业务费专项基金项目(DL13EA05-02)、国家自然科学基金项目(41471168、31370463)、教育部新世纪优秀人才支持计划项目(NCET-12-0810)、黑龙江省归国留学基金项目(LC2012C09)。 （DL13EA05-02）
