西藏色季拉山急尖长苞冷杉林粗木质残体储量与倒木分解研究  

Studies on the Reserves of Coarse Woody Debris and Decomposition of Fallen Trees in Abies georgei var.smithii Forest of Sygera Mountains in Tibet

作　　者：马豪霞 任毅华[2] 侯磊[1] 王博文[1] 郑维列[2] 

机构地区：[1]西藏大学农牧学院资源与环境学院,西藏林芝860000 [2]西藏大学农牧学院高原生态研究所,西藏林芝860000

出　　处：《西北林学院学报》2016年第5期68-73,共6页Journal of Northwest Forestry University

基　　金：西藏自治区自然科学基金项目(2015ZR-14-24);西藏大学农牧学院2014年提升综合实力建设项目(生态学科)

摘　　要：粗木质残体是森林生态系统重要的组成部分,在生态系统的结构组成和功能发挥中扮演着重要角色。采用典型样地法对色季拉山急尖长苞冷杉(Abies geoegei var.smithii)原始林下的粗木质残体进行调查,估算林内粗木质残体的储量,并比较不同腐烂等级及不同类型粗木质残体储量的大小,分析南坡与北坡2种不同环境下倒木分解速率的差异。结果表明,色季拉山南北坡急尖长苞冷杉的粗木质残体的储量分别为84.245t·hm^(-2)和60.363t·hm^(-2),两者储量在不同类型的分布上均表现为倒木>枯立木>树桩>大枯枝;在不同腐烂等级分布上,南坡粗木质残体储量表现为Ⅰ级>Ⅳ级>Ⅱ级>Ⅲ级>Ⅴ级,北坡粗木质残体储量表现为Ⅰ级>Ⅱ级>Ⅲ级>Ⅳ级>Ⅴ级。色季拉山南北坡急尖长苞冷杉林倒木的分解均符合单指数衰减模型,南北坡的分解常数分别为0.014a-1(R2=0.870 3)、0.02a-1(R2=0.846 5)。南坡倒木分解50%和95%所需时间分别为29a和193a,北坡分解50%和95%所需时间分别为41a和156a,两者分解均呈现先快后慢的趋势。Coarse woody debris is an important component of forest ecosystem, and plays an important role in the structure and function of the ecosystem. This paper used typical sample plot method to investigate the coarse woody debris in Abies georgei var. smithii forest in Sygera Mountains, Tibet. We estimated the reserves of coarse woody debris in the forest, and compared the sizes of reserves in different decay grades and different types of coarse woody debris and analyzed the decomposition rate of fallen trees in two different locations （the south and north slope）. The results showed that the reserves of coarse woody debris in A. georgei var. smithii forest of Sygera Mountains in south and north slope were 84. 245 t · hm-2 and 60. 363 t · hm 2 respectively. The distribution of reserves of the different types presented an order of blow-down,dead standing tree〉 stump〉large dead branches both in south and north slope. The distribution of reserves of different decay grades were in the order of Ⅰ 〉 Ⅳ 〉 Ⅱ 〉 Ⅲ 〉 Ⅴ in south slope and Ⅰ 〉 Ⅱ 〉 Ⅲ 〉 Ⅳ 〉 Ⅴ in north slope. The decomposition of fallen trees in was in line with the single exponential decay model. The decomposition constants in the north and south slope were 0. 014 a-1 （R^2 =0. 870 3） ,0. 02 a ^-1 （R^2 =0. 846 5） ,respectively. The time for 50% and 95% decomposition of fallen trees were 29 a and 193 a in the southern slope,and 41 a and 156 a in the north slope. The decomposition rates in two slopes were presented a downward trend.

关 键 词：急尖长苞冷杉 粗木质残体 储量 倒木分解 

分 类 号：S718.554[农业科学—林学]