在模拟森林火灾的加热实验中,燃烧性溶解有机物质的温度值
Qiang Zhang1,2,3,4, Yinghui Wang2,3,4, Ping Guan5
1School of Environment, Harbin Institute of Technology, Harbin 150090, China.
Environmental science & technology
|November 2, 2023
概括
森林火灾的加热温度对热生成溶解有机物 (DOM) 有重大影响. 这项研究确定了DOM生产和损失的特定温度值,揭示了特定组件的野火对土壤有机物的影响.
科学领域:
- 环境化学环境化学
- 土壤科学 土壤科学
- 有机地化学 有机地化学
背景情况:
- 森林火灾会产生高烧性溶解有机物 (DOM),影响土壤的特性.
- 加热温度 (HT) 是一个关键因素,但对于DOM生产和损失的组件特定值是未知的.
研究的目的:
- 在特定组件的基础上确定最大DOM产量 (TTmax) 和净DOC损失 (TT0) 的温度值.
- 为了分析DOM的组成变化,在碎片和土壤中使用不同的HT.
主要方法:
- 固态13C核磁共振光谱学 固态13C核磁共振光谱学
- 吸收和光光谱仪的吸收和光光谱仪.
- 里叶变换离子循环子共振质谱法 (FTICR-MS)
- 从150-500°C加热的碎片和土壤中分析DOM.
主要成果:
- 大量溶解有机碳 (DOC) 和大多数DOM成分的TTmax在碎片和土壤中都在225-250°C之间.
- TT0在碎片中的含量始终低于在土壤中的含量.
- 不同的DOM组件表现出明显的净损失温度值,首先是碳水化合物/阿利法基,其次是蛋白质/多基,最后是缩芳基.
- 在TT0以下燃烧,特别是在TTmax时,增加了DOC数量,可能会增强微生物的不稳定基质.
结论:
- 野火对土壤有机物的影响是非线性的,取决于温度和DOM组件.
- 了解特定组件的温度值对于预测火灾后土壤有机物动态和生态系统恢复至关重要.
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