亚热带森林景观中可溶性有机碳的时空格局及土壤截存机制

项目名称： 亚热带森林景观中可溶性有机碳的时空格局及土壤截存机制

项目编号： No.31470526

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 生物科学

项目作者： 刘峰

作者单位： 中国科学院武汉植物园

项目金额： 88万元

中文摘要： 可溶性有机碳（DOC）是陆地碳库中最活跃的一个部分，它的持续流动是碳流失的重要途径，也是氮、磷等其他生源要素及重金属、污染物等转移的载体。所以说DOC是准确估计森林景观碳预算必不可少的一部分。现有的研究大多集中于DOC的组成、动态及影响因素，而对景观中DOC的空间异质性涉及不多。DOC在土壤内的垂直运动是生态系统碳转移、积累和固存的关键，但我们对其机制知之甚少。特别是在全球变化的背景下，深入了解DOC 在土壤中的截存机制及控制因素是准确估计土壤碳固存潜力和评估碳固存措施的必要条件。因此，本项目拟（1）通过调查DOC在森林景观内的时空格局来量化其空间异质性及其主要影响因子；（2）通过室内土壤培养实验，利用生物标记物和稳定性同位素技术，探索DOC在不同深度土壤中的矿化动态及其控制因子。本研究的预期结果将加强我们对DOC转移动态和截存机制的了解，为全球变化背景下如何增加土壤碳固存提供理论支持。

中文关键词： 可溶性有机碳；森林景观；碳固存；生物标记物；时空格局

英文摘要： Dissolved organic carbon (DOC) is the most dynamic component in the carbon pool of terrestrial forest landscapes. The continuous flow of DOC within and outside forest ecosystems is a key pathway for carbon movement, and transport of biogenic elements, heavy metals and pollutants. Many studies have examined the composition, dynamics and controlling factors for DOC, but few has explored its spatial and temporal pattern in a forest landscape. The downward movement of DOC in the soil profile, associated with changes in concentration and composition, is a major mechanism for carbon sequestration and accumulation. Better understanding of this mechanism and its controlling factors would help us improve the estimation carbon budget for a forest landscape and evaluate future possible management practices to increase carbon sequestration. In this study, we are going to quantify the spatial and temporal dynamics of DOC in a subtropical forest landscape in central China. We will also conduct an incubation experiment to study how adding DOC to soils from different depth may affect the dynamics of carbon sequestration and decomposition. Biomarkers and stable isotopes will be utilized to track the fate of carbon during the incubation. Results of this study will provide critical information on how DOC may affect carbon accumulation and sequestration in forest landscapes, and shed new light on how we may manage the forests for carbon sequestration.

英文关键词： forest landscape;dissolved organic carbon;spatial temporal pattern;carbon sequestration;biomarker