Biogeochemical interface formation in soils as controlled by different components

土壤中生物地球化学界面的形成受不同成分的控制

• 批准号: 40976401
• 负责人: Professorin Dr. Ingrid Kögel-Knabner
• 金额: --
• 依托单位: Lehrstuhl für Bodenkunde
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/40976401?language=en
• 关键词: Biogeochemical; interface; formation; soils; controlled

We consider clay minerals, iron oxides and charcoal as major components controlling the formation of interfaces relevant for sorption of organic chemicals, as they control the assemblage of organic matter and mineral particles. We studied the formation of interfaces in batch incubation experiments with inoculated artificial soils consisting of model compounds (clay minerals, iron oxide, char) and natural soil samples. Results show a relevant contribution of both iron oxides and clay minerals to the formation of organic matter as sorptive interfaces for hydrophobic compounds. Thus, we intend to focus our work in the second phase on the characterization of the interface as formed by organic matter associated with clay minerals and iron oxides. The interfaces will be characterized by the BET-N2 and ethylene glycol monoethyl ether (EGME) methods and 129Xe and 13C NMR spectroscopy for determination of specific surface area, sorptive domains in the organic matter and microporosity. A major step forward is expected by the analysis of the composition of the interface at different resolution by reflected-light microscopy (mm scale), SEM (scanning electron microscopy, micrometer scale) and secondary ion mass spectrometry at the nanometer scale (nanoSIMS). The outcomes obtained in combination with findings from cooperation partners will help to unravel the contribution of different types of soil components on the formation and characteristics of the biogeochemical interfaces and their effect on organic chemical sorption.

我们认为粘土矿物、氧化铁和木炭是控制与有机化学物质吸附相关的界面形成的主要成分，因为它们控制着有机物和矿物颗粒的组合。本文研究了由模型化合物（粘土矿物、氧化铁、炭）和天然土壤样品组成的接种人工土壤的间歇培养实验中界面的形成。结果表明，氧化铁和粘土矿物作为疏水化合物的吸附界面，对有机物质的形成有一定的贡献。因此，我们打算将第二阶段的工作重点放在与粘土矿物和氧化铁相关的有机物质形成的界面的表征上。用BET-N2和乙二醇单乙醚（EGME）方法对界面进行表征，用129Xe和13C NMR谱法测定其比表面积、有机物的吸附域和微孔隙度。利用反射光显微镜（毫米尺度）、扫描电子显微镜（微米尺度）和二次离子质谱在纳米尺度（nanoSIMS）上对不同分辨率的界面成分进行分析，有望取得重大进展。这些结果与合作伙伴的发现相结合，将有助于揭示不同类型土壤成分对生物地球化学界面的形成和特征的贡献及其对有机化学吸附的影响。