Processes of belowground carbon cycling in the plant-mycorrhiza-soil system as affected by silvicultural management

造林管理对植物-菌根-土壤系统地下碳循环过程的影响

• 批准号: 42021277
• 负责人: Professor Dr. Georg Guggenberger
• 金额: --
• 依托单位: Institut für Bodenkunde (IFBK)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2010-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/42021277?language=en
• 关键词: Processes; belowground; carbon; cycling; plant

With this extention proposal we want to finalize our studies on processes controlling the belowground carbon cycling. In the natural forest, we are comparing carbon allocation in the system plant-soil-atmosphere for different functional types of trees, including Croton macrostachyus, Podocarpus falcatus, and Prunus africana. Within the silvicultural experiments we are focusing on Cupressus lusitanica stands under conventional management and intensive promotion. After whole tree 13C labelling, the labelled carbon will be chased for one year in the leaves, phloem sap, roots and associated microorganisms, and soil and physical soil fractions. This will allow to comparatively investigating the flux of recent assimilates from the plant to the mycorrhiza and soil, and back to the atmosphere, including the separation of autotrophic from heterotrophic soil respiration. As an independent approach, organic carbon transfer from plant to soil, its turnover in the soil, and the source of soil CO2 efflux will be also studied by the 14C approach, including natural abundance and the ‘bomb’ derived 14C. We expect from the results important information on plant-soil organic carbon cycling and storage in soil, and on the consequences of the shift of different functional types of trees due to increasing degradation. For the silvicultural plots, important information on the impact of thinning on the carbon allocation and soil carbon storage can be foreseen.

通过这一扩展建议，我们希望完成我们对控制地下碳循环过程的研究。在天然林中，我们比较了不同功能类型的树木，包括大穗巴豆，Podocarpus falcatus和Prunus africana在植物-土壤-大气系统中的碳分配。在造林试验中，我们的重点是常规管理和密集推广下的墨西哥柏。全树13 C标记后，标记碳将在叶、韧皮部汁液、根和相关微生物以及土壤和物理土壤组分中追踪一年。这将允许比较调查最近同化物从植物到菌根和土壤的通量，并返回到大气中，包括自养和异养土壤呼吸的分离。作为一种独立的方法，14 C方法还将研究有机碳从植物到土壤的转移、其在土壤中的周转以及土壤CO2排放的来源，包括自然丰度和“炸弹”衍生的14 C。我们期望从结果的重要信息植物土壤有机碳循环和土壤中的存储，以及不同功能类型的树木，由于日益退化的转变的后果。对于造林样地，可以预见间伐对碳分配和土壤碳储量的影响的重要信息。