Response of belowground carbon, sulphur and iron cycling in fen soils

沼泽土壤地下碳、硫、铁循环的响应

• 批准号: 5445005
• 负责人: Professor Dr. Christian Blodau (†)
• 金额: --
• 依托单位: Arbeitsgruppe Ökohydrologie und Stoffkreisläufe
• 依托单位国家: 德国
• 项目类别: Research Units
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5445005?language=en
• 关键词: Response; belowground; carbon; sulphur; iron

Climate models predict increases in summer drought and intensive rainfalls in temperate and northern latitudes, which may alter the hydrologic and redox regime of wetlands, the single most important terrestrial carbon storage. The impact of drying and rewetting and potential inundation on ecosystem production and belowground carbon cycling and the coupling with redox processes, in particular of sulfur and iron, is not well understood to date. In this project the hydrologic regime of a wetland will be altered experimentally and the consequences on carbon cycling be analyzed and simulated. To this end, changes in soil water contents, temperatures and respiration rates will be quantified during and after manipulation. The availability, production, and consumption of relevant electron acceptors for respiration, i.e. oxygen, nitrate, sulfate, ferric iron, humic substances, is studied, as their dynamics strongly influences methane production. A laboratory study will serve to analyze the impact of a range of temperatures and drying intensity and duration on respiration. The obtained data will be combined with the data of the previous controlled mesocosm and field study to simulate the impact of hydrologic change on carbon cycling and methane dynamics using the ecosystem model ECOSYS. The parameterized and tested model will be used to simulate and analyze the interaction of biogeochemical processes occurring during drying and rewetting and the impact on carbon cycling on the decadal time scale.

气候模型预测，夏季干旱的增加以及温带和北部纬度的强化降雨，这可能会改变湿地的水文和氧化还原状态，湿地是最重要的陆生碳存储。迄今为止尚未很好地了解干燥和重新吹释以及潜在的淹没对生态系统生产和地下碳循环以及与氧化还原过程的耦合，尤其是硫和铁的耦合的影响。在该项目中，将对湿地的水文制度进行实验改变，并对碳循环的后果进行分析和模拟。为此，在操纵过程中和之后，将量化土壤水含量，温度和呼吸速率的变化。研究了相关电子受体的可用性，生产和消耗呼吸器，即氧气，硝酸盐，硫酸盐，铁，铁，腐殖质物质，因为它们的动力学强烈影响甲烷的产生。一项实验室研究将有助于分析一系列温度以及干燥强度和持续时间对呼吸的影响。所获得的数据将与先前受控中术和现场研究的数据结合使用，以模拟使用生态系统模型Ecosys对水文变化对碳循环和甲烷动力学的影响。参数化和测试的模型将用于模拟和分析在干燥和重新吹干过程中发生的生物地球化学过程的相互作用，以及对十年时间尺度上碳循环的影响。