与土壤接触会影响化和化在土中氧化还原循环期间的变化
Katrin Schulz1, Luiza Notini1, Andrew R C Grigg1
1Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, Department of Environmental Systems Science, ETH Zurich, Universitätstrasse 16, CHN, CH-8092 Zurich, Switzerland.
Environmental science. Processes & impacts
|November 16, 2023
概括
土壤矩阵相互作用显著改变了氧化氧化氧化氧化铁在氧化还原循环中的转化. 纯铁矿物质形成晶体相,而与土壤相关的矿物质产生无序的反应相,影响土壤元素循环.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 土壤科学 土壤科学
背景情况:
- 铁 (Fe) 氧化在还原条件下经历了还原性溶解和转化,影响矿物质结晶性和吸能力.
- 在自然土壤条件下了解这些氧化氧化转变至关重要,但仍然不太了解.
研究的目的:
- 为了研究土壤矩阵接触对氧化氧化氧化在氧化还原循环期间变化的影响.
- 阐明在米土壤中等宇宙中铁化和勒皮多克罗赛特转变的途径和速率.
主要方法:
- 在米土壤中,在网袋中化铁和勒皮多克罗,持续12周.
- 应用三个还原-氧化循环 (洪水和排水).
- 使用Fe K边缘X射线吸收细结构光谱,X射线衍射和57Fe Mössbauer光谱分析Fe矿物成分.
主要成果:
- 在没有土壤的情况下,铁和勒皮多克罗西特转化为磁石和/或戈伊.
- 在矿物土壤混合物中,57Fe-ferrihydrite转化为一个混乱的混合价值Fe (II) -Fe (III) 阶段,57Fe-lepidocrocite形成goethite和一个混乱的Fe阶段.
- 在矿物土壤混合物中的氧化还原循环增加了还原性溶解,在氧化时期降水.
结论:
- 土壤基质显著影响铁氧化氧化物转化,特别是当与矿物密切接触时.
- 与土壤的密切联系导致由铁化形成无序的,反应性Fe相,而不是晶体产品.
- 在土壤矩阵的存在下,勒普托克罗赛特转化向戈希特被促进.
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