| 摘要: |
| 【目的】探讨藏东南原始林生长季土壤呼吸特征，以了解藏东南亚高山森林生态系统土壤碳循环过程及其关键驱动因子。【方法】在色季拉山东坡林芝云杉林和急尖长苞冷杉林中各设置典型样地3块，用LI 8100土壤碳通量仪测定土壤呼吸速率，并取土样测定其理化特性，以此分析2种原始林土壤呼吸速率的变化规律及影响因子。【结果】（1）林芝云杉林和急尖长苞冷杉林土壤呼吸速率日变化均呈近似“n”型，日平均土壤呼吸速率分别为（3.25±0.74）和（2.95±0.62） μmol/(m2·s)；不同月份下2种原始林土壤呼吸速率均表现为7月＞8月＞6月，同月份下为林芝云杉林大于急尖长苞冷杉林；林芝云杉林土壤呼吸速率对温度的响应较急尖长苞冷杉林敏感。（2）林芝云杉林和急尖长苞冷杉林土壤呼吸速率与土壤温度均呈极显著指数正相关（R2分别为0.75和0.94），而与土壤湿度呈极显著线性负相关（R2分别为0.71和0.79）。（3）林芝云杉林和急尖长苞冷杉林土壤日碳通量与土壤有机碳呈极显著指数正相关（R2分别为0.91和0.82），而与微生物量碳呈极显著指数负相关（R2分别为0.88和0.89）。【结论】西藏暗针叶林生长季土壤呼吸主要受土壤温度和水分调控，也与土壤有机碳和微生物量碳密切相关。 |
| 关键词: 原始暗针叶林 土壤呼吸 土壤理化特性 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目（41061033，31460122，31360119）；西藏林芝森林生态系统定位研究项目（2012-LYPT-DW-016）；西藏自治区自然科学基金项目（2015-2016） |
|
| Soil respiration characteristics of primitive dark coniferous forests during growing season in southeast Tibet |
|
GUO Qiqiang,MA Heping,QIAN Dengfeng,et al
|
| Abstract: |
| 【Objective】Study on soil respiration characteristics of virgin dark coniferous forests in southeast Tibet was conducted to understand course and key driving factors of soil respiration rate.【Method】Respiration rate of soil was determined by using the LI-8100 soil carbon flux determinator,and the physical and chemical characteristics of the soil samples were further measured,all these indicators were used to analyze the respiration rate of soil and the related environment factors in three typical plots of Picea likiangensis var.linzhiensis forest and in three typical plots of Abies georgei var.smithii forest on the eastern slope of Sejila Mountain.【Result】The diurnal variation of soil respiration rates was in “n” shape curve in P.likiangensis var.linzhiensis forest and A.georgei var.smithii forest with daily average values of （3.25±0.74） and （2.95±0.62） μmol/(m2·s).The soil respiration rates were in a decreasing order of July>August>June in both virgin forests,and P.likiangensis var.linzhiensis forest had higher values than A.georgei var.smithii forest in each month.The response of soil respiration rate of P.likiangensis var.linzhiensis forest to temperature was more sensitive than that of A.georgei var.smithii forest.A significant positive exponential correlation was found between soil respiration rate and soil temperature in P.likiangensis var.linzhiensis forest and A.georgei var.smithii forest (R2 are 0.75 and 0.94,separately),while a significant negative linear correlation existed between soil respiration rate and soil water content (R2 are 0.71 and 0.79,separately).Diurnal carbon flux and organic carbon in soil were in significantly positive exponential correlation (R2 are 0.91 and 0.82,separately) in P.likiangensis var.linzhiensis forest and A.georgei var.smithii forest,while diurnal carbon flux and microbial biomass carbon in soil were in significant negative exponential correlation (R2 are 0.88 and 0.89,separately).【Conclusion】Temperature and water content of soil in virgin dark coniferous forests were the main factors for regulating soil respiration rate.They also closely related with organic carbon and microbial biomass carbon in soil. |
| Key words: primitive dark coniferous forests soil respiration soil physical and chemical characteristics |
