西藏色季拉山典型天然暗针叶林土壤碳库特征研究  

Research on Soil Organic Carbon Pool of Typical Natural Dark Coniferous Forests in Sygara Mountains in Tibet

作　　者：周晨霓[1] 任毅华[1] 马和平[1] 郭其强[1] 

机构地区：[1]西藏大学农牧学院高原生态研究所,西藏林芝860000

出　　处：《环境科学与技术》2015年第6期1-7,共7页Environmental Science & Technology

基　　金：国家自然科学基金项目(41061033);西藏色季拉山国家森林生态定位站开放项目(XZA-211-0713-D)

摘　　要：西藏亚高山暗针叶林森林植被是我国重要的生态屏障,对全球陆地生态系统的碳收支平衡起着举足轻重的作用。该研究选取西藏色季拉山2种最典型的天然暗针叶林：急尖长苞冷杉（Abies georgei var.smithii）和林芝云杉（Picea likiangensis var.linzhiensis）为研究对象,测定其土壤有机碳含量和微生物量碳含量,并动态监测其土壤呼吸及其各呼吸组分速率,结果表明：2种植被类型的SOC含量和SMBC含量均具有明显的表聚性,表层（0~20 cm）SOC含量分别占各层土壤总SOC含量的52.55%（林芝云杉）和51.87%（急尖长苞冷杉）,而表层（0~20 cm）SMBC含量占各层土壤总SMBC含量的64.24%（林芝云杉）和65.48%（急尖长苞冷杉）;2个林型8-9月份土壤呼吸值最高,12月份最低,土壤呼吸最大值分别为6.27μmol/（m^2·s）（急尖长苞冷杉）、4.91μmol/（m^2·s）（林芝云杉）。指数回归方程可以很好地描述土壤呼吸速率与土壤温度之间的相关关系,除了急尖长苞冷杉林的枯枝落叶呼吸外,其他的呼吸组分及林芝云杉各呼吸组分速率均与土壤水分含量呈显著的一元线性关系（P〈0.05）。2种林分的微生物呼吸占总呼吸量的比例最高,其次为枯枝落叶呼吸和根系呼吸。微生物呼吸在夏秋季所占比例较高,根系呼吸在春夏季所占比例较高,枯枝落叶呼吸则在春末夏初所占比例较高。The virgin forest in Tibetan Plateau as an important ecological barrier of China, plays a decisive role on global terrestrial ecosystem carbon balance. This research chose the most two typical natural forest in Sygara Mountain （Abies georgei var. smithii and Picea likiangensis var. linzhiensis） as the object, measured the content of soil organic carbon （SOC） and the soil respiration and its components of the forests, and results showed that the content of SOC and soil microbial biomass carbon （SMBC） of these two kinds of forests had the significant characteristic of surface accumulation. The content of SOC in the surface soil （0-20 cm） accounted for 52.55%（Picea likiangensis var. linzhiensis） and 51.87%（Abies georgei var. smithii） of total SOC content, while the content of SMBC in the surface soil （0-20 cm） accounted for 64.24% （Picea likiangensis var. linzhiensis） and 65.48%（Abies georgei var. smithii） of total SMBC content. The maximum value of soil respiration was in August to September, and the minimum value was in December, with the maximum value of soil respiration of these two forests as 6.27 μmol/（m^2·s ）（Abies georgei var. smithii）and 4.91 μmol/（m^2·s ）（Picea likiangensis var. linzhiensis）. The relationship between SRR and soil temperature and water contents can be described by exponential equation and linear equation. But there was no significant relationship between SRR and soil water content of Abies georgei var. smithii. Microbial respiration had the highest percentage of these two forests, then followed with leaf respiration and root respiration. Microbial respiration had higher percentage in summer and autumn, while root respiration had higher percentage in spring and summer, leaf respiration had higher percentage in late spring and early summer.

关 键 词：土壤有机碳 土壤呼吸 西藏 色季拉山 

分 类 号：X144[环境科学与工程—环境科学]