土壤中气和非地质甲和二氧化碳的惊人的度令人惊
G Etiope1, G Ciotoli2, E Benà3
1Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 2, Rome, Italy; Faculty of Environmental Science and Engineering, Babes-Bolyai University, Cluj-Napoca, Romania.
The Science of the total environment
|July 20, 2024
概括
意大利阿尔卑斯山土壤中高度的气 (H2) 并非来自地质来源. 相反,湿土中的微生物发酵产生了H2,甲 (CH4) 和二氧化碳 (CO2).
科学领域:
- 地质化学 地质化学
- 微生物学 微生物学
- 环境科学 环境科学
背景情况:
- 自然 (H2) 被研究为一种无碳能源.
- 在土壤中接近表面的H2通常是深层地质气体泄漏的指标.
- 微生物对H2的消耗会影响其近地表检测.
研究的目的:
- 调查意大利阿尔卑斯山草原土壤中意外高度的H2的来源.
- 要区分土壤气体 (H2,CH4,CO2) 的地质和微生物来源.
- 为H2勘探和土壤温室气体研究提供新的见解.
主要方法:
- 气体地质化学分析,包括散装和聚集的CH4同位素和CH4和CO2的放射性碳测年.
- 土壤微生物学分析,包括DNA和mcrA基因定量聚合酶连锁反应.
- 评估气体结合 (H2-CO2-CH4-H2S) 和环境条件 (土壤水分).
主要成果:
- 在意大利阿尔卑斯山土壤中,H2的广泛存在 (高达1体积%) 与CH4和CO2的高存在.
- 同位素和遗传分析证实H2与现代微生物活动有关,而不是地质来源.
- 观察到的气体成分和湿土条件表明近地表发酵.
结论:
- 土壤中高度的H2 (高达1体积%) 并不一定表明地质深度的H2透.
- 在某些土壤环境中,微生物发酵是H2,CH4和CO2的重要来源.
- 这一发现需要重新评估H2勘探指南和土壤气体循环研究.
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