The Magnitude and Drivers of Sediment Methane Production in Streams across Europe

欧洲河流中沉积物甲烷产生的规模和驱动因素

• 批准号: 390018681
• 负责人: Dr. Pascal Bodmer
• 金额: --
• 依托单位: Chaire de recherche industrielle sur la Biogéochimie du Carbone des Écosystèmes Aquatiques Boréaux (BiCÉAB)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/390018681?language=en
• 关键词: Magnitude; Drivers; Sediment; Methane; Production

Fluvial systems (streams and rivers) have been recently recognized as a globally significant source of atmospheric CH4. Hence, many studies measure gaseous CH4 fluxes at the sediment-water interface or at the water-air interface. However, the combination of various pathways of potential gaseous methane fluxes to the atmosphere with the stochastic nature of ebullition events lead to large uncertainties in averaged flux estimates. Assessing the potential production and oxidation rates of methane, i.e. focusing on the processes that control CH4 production and loss, may represent an alternative approach compared to flux measurements. However, the driving factors of these processes and their spatial variability in streams are not yet fully understood. The overall goal of this proposed project is, according to our knowledge for the first time, to estimate the spatial variability of potential methane production and oxidation rates (PMP and PMO) and their driving factors in stream sediments at two spatial scales: the stream reach scale and the continental scale. In order to archive this goal, the proposed project uses the framework of a currently ongoing European wide project: EuroRun (Assessing CO2 fluxes from European running waters). EuroRun consists of 16 teams all located at different places in 11 European countries. Each EuroRun team will samples sediment samples in one stream across Europe and send them to the University of Koblenz-Landau, where the principle investigator of the project will measure PMP and PMO as well as sediment characteristics of the respective samples (organic matter quality as sediment carbon to nitrogen content, grain size distribution). A successful execution of the proposed project will strongly enhance the current understanding of CH4 production in streams. Furthermore, the investigation of potential drivers of PMP and PMO at continental scale may provide important parameters which can be implemented in a process-based model, predicting CH4 production and consequently emission dynamics in stream ecosystems.

河流系统(溪流和河流)最近被认为是大气CH4的全球重要来源。因此，许多研究测量了沉积物-水界面或水-空气界面的CH4气体通量。然而，潜在的气态甲烷通量进入大气的各种途径与沸腾事件的随机性质相结合，导致平均通量估计的很大不确定性。与通量测量相比，评估甲烷的潜在生产和氧化速率，即侧重于控制甲烷生产和损失的过程，可能是一种替代办法。然而，这些过程的驱动因素及其在河流中的空间变异性尚不完全清楚。据我们所知，这一拟议项目的总体目标是首次在两个空间尺度上估计水系沉积物中潜在甲烷生产和氧化速率(PMP和PMO)及其驱动因素的空间变异性：河流河段尺度和大陆尺度。为了实现这一目标，拟议的项目使用了目前正在进行的欧洲范围项目的框架：EuroRun(评估欧洲自来水的二氧化碳通量)。EuroRun由16支球队组成，全部分布在11个欧洲国家的不同地点。每个EuroRun团队将在整个欧洲的一条河流中采集沉积物样本，并将其送往科布伦茨-朗道大学，项目的首席调查员将在那里测量PMP和PMO以及各自样本的沉积物特征(有机质质量，如沉积物碳氮含量、粒度分布)。拟议项目的成功执行将极大地加强目前对河流中甲烷生产的了解。此外，对大陆尺度上PMP和PMO的潜在驱动因素的调查可以提供重要的参数，这些参数可以在基于过程的模型中实施，从而预测河流生态系统中CH4的产生和排放动态。