在全球大湖中氧化甲光生成
Jikang You1,2, Chongsen Duan1,2, Fei Liu1
1Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
Environmental science & technology
|August 11, 2025
概括
全球湖泊通过氧化甲 (CH4) 光生成为甲预算做出贡献. 这一过程在赤道和高海拔湖泊中尤为显著,影响水生生态系统的甲排放.
科学领域:
- 环境科学 环境科学
- 生物地质化学生物地质化学
- 遥感 遥感 遥感 遥感
背景情况:
- 全球甲 (CH4) 预算存在不一致性,需要更好地估计来自不同来源的CH4排放量.
- 水生生态系统,特别是湖泊,是大气甲的重要来源,但它们的贡献尚未完全量化.
- 在湖泊中氧化甲光生成的作用仍未得到充分研究,尽管它对整体CH4预算的潜在贡献.
研究的目的:
- 研究全球湖泊中氧化甲 (CH4) 光生成潜力的时空模式.
- 量化氧化CH4光生成对湖泊中扩散性CH4流量的贡献.
- 估计来自湖泊中氧气光生成的全球CH4预算.
主要方法:
- 利用基于遥感的光化学模型来评估氧化CH4的光生成潜力.
- 用于流量计算的CH4到CO (ΔCH4/ΔCO) 的在实验室中确定的光生成分子比率.
- 分析了2011-2020年全球100平方公里以上湖泊的数据.
主要成果:
- 中国湖泊 (2011-2020年) 中的氧化CH4光生成潜力在空间上有所变化,与浅浅的环氧化东部湖泊相比,深度较低的西部湖泊的比率更高.
- 在全球范围内,湖泊中的平均氧化CH4光生成潜力为1.27e-6mol (CH4) m−2天−1 (2011-2020).
- 赤道地区和高海拔地区的湖泊显示出更高的比率,而高度湖泊的比率较低. 氧化光生成占散射CH4流量的0.1-22%,全球估计总计为0.0104 Tg CH4/年.
结论:
- 氧化甲 (CH4) 光生成是水生生态系统中一个重要的,以前被低估的过程.
- 这个过程在全球甲循环中起着不可忽视的作用,为整体CH4预算做出了贡献.
- 这些发现为完善全球CH4预算和了解水中CH4排放提供了关键数据.
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