鳞毛蕨天山云杉林粗死木质残体贮量及其分解动态  

Storage and decomposition dynamics of coarse woody debris in Picea schrenkiana-Dryopteris filix-mas stand

作　　者：刘翠玲[1] 潘存德[1] 梁瀛[2] 

机构地区：[1]新疆农业大学林学院,新疆乌鲁木齐830052 [2]新疆林业科学院,新疆乌鲁木齐830000

出　　处：《干旱区地理》2009年第2期175-182,共8页Arid Land Geography

基　　金：国家自然科学基金(30360087;39960063);新疆维吾尔自治区高校科学研究计划资助(XJEDU2004E08)

摘　　要：为了丰富我国森林粗死木质残体研究的对象类型,并为探讨粗死木质残体在天山云杉天然更新中的生态作用奠定基础,借助粗死木质残体5级分类系统,采用临时标准调查法对西天山国家级自然保护区原始鳞毛蕨天山云杉纯林粗死木质残体的贮量、养分含量及其分解动态进行了研究。结果表明:(1)鳞毛蕨天山云杉林粗死木质残体体积贮量为337.61 m^3/hm^2,生物量为87.98 mg/hm^2;倒木树干是粗死木质残体的主体组成部分,占总体积的98.09%;(2)以基本密度(比重)为衡量指标,倒木腐朽等级越高,其密度越小,倒木分解符合单项指数衰减模型,分解常数为0.011 74。5个不同腐朽等级倒木的平均滞留时间依次为4年、18年、38年、68年和92年。在自然状态下,倒木分解50%、90%和95%所需时间分别为59年、196年和255年;(3)倒木有机碳、全N、全P、全K、Na^+的平均含量依次为55.93%±1.42%、0.34%±0.07%、0.12%±0.01%、0.06%±0. 01%和0.03%±0.002%,Ca^(2+)、Mg^(2+)的平均含量分别为56.74±4.87 g/kg和34.89±3.66 g/kg,不同养分的变化趋势不同,但同一养分在不同腐朽等级倒木之间的差异不显著。Coarse woody debris （ CWD）, a consequence of a forest＇ s natural disturbance, is important to many ecological and physical processes in forest dynamics. CWD supplies the safe site for germination and improves the forest dynamics. In order to enrich research of coarse woody debris and discuss ecological functions of coarse woody debris in the course of Picea schrenkiana natural regeneration, this paper focuses on the study of storage, decomposition dynamics and nutritious content of CWD in Picea schrenkiana-Dryopterisfilix-mas stand in the Western Tianshan Mountains National Nature Reserve by the method of temporary sample. CWD is classified by the actual status of Picea schrenkiana log exterior characteristics using the international traditional five-class system. All CWD, including messy branches, twigs （diameter≥2.5 cm） and trunks of fallen logs, their species, number and decomposition class are recorded using the Picea schrenkiana five-class system in field. And the same time, density and nutritious content of CWD are determined in laboratory. The results indicate that all CWD are Picea schrenkiana branches, twigs and fallen logs. The volume of all CWD is 337.61 m^3/hm^2. Moreover, trunk of fallen wood is primary composition of CWD, reaching 98.09 percentages. By measuring the CWD density, the biomass of all CWD is 87.98 mg/hm^2. Based on the fallen wood density, the results show that the higher decomposition class is, the lower its density is. And the relationship between decomposition classes and the fallen wood density can be modeled as a negative exponential function, and the decomposition rate constant is 0. 011 74. The decomposition time of each class is 4 a, 18 a, 38 a, 68 a, and 92 a, respectively. Under the nature condition, the decomposition time that the fallen wood density decreases 50%, 90% and 95% is approximately 59 a, 196 a and 255 average percent of C, N, P, K and Na^＋ is 55.93 ± 1.42% , 0.34 ± 0.07% ,0. 12 ± 0. 01% ,0.06±0.01%, 0.03±0. 002% , the average content of Ca^2＋

关 键 词：天山云杉 粗死木质残体 倒木 腐朽等级 贮量 分解 养分含量 

分 类 号：S718.4[农业科学—林学]