SGER: High-Resolution, In Situ Measurements of Metabolic Gas Profiles in Sediments

测量代谢气体（如CO2、CH4、O2、H2和其他气体）浓度的能力，可以深入了解与土壤或沉积物相关的生物地球化学过程。这些代谢气体的高分辨率测量受到从沉积物中取样孔隙水的困难和孔隙水取样引起的干扰的限制。该研究项目将使用电池供电的便携式质谱仪和小型半透性探针在现场测量挥发性气体。基本便携式质谱仪已经研制成功。目前的研究将集中在开发一种可以直接插入沉积物的合适探针，以及增加质谱仪本身。该系统将在泥炭地沉积物中进行测试，在泥炭地沉积物中，甲烷、氧气、二氧化碳的分布和梯度对于理解微量气体与大气交换的机制非常重要。由于该系统基于质谱仪，因此也具有支持原位稳定同位素富集研究的潜力。

The ability to measure concentrations of metabolic gases, such as CO2 CH4, O2, H2 and others, can provide insights into biogeochemical processes associated with soils or sediments. Measurement of these metabolic gases with high resolution is limited both by the difficulty of sampling porewaters from sediments and by disturbances caused by porewater sampling. This research project will measure volatile gases in situ using a battery-operated portable mass spectrometer and a small semi- permeable probe. The basic portable mass spectrometer has already been developed. The present research will focus on development of a suitable probe that can be directly inserted into sediments, as well as augmentation of the mass spectrometer itself. The system will be tested in peatland sediments where distributions and gradients of methane, oxygen, carbon dioxide are important for understanding the mechanisms of trace gas exchange with the atmosphere. The proposed system, because it is based on a mass spectrometer, also has the potential to support in situ stable isotope enrichment studies.