热带植物强烈排放甲基化物
Yoko Yokouchi1, Masumi Ikeda, Yoko Inuzuka
1National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan. yokouchi@nies.go.jp
Nature
|March 15, 2002
概括
热带植物如和Dipterocarpaceae是甲基化物的重要天然来源,甲基化物是一种破坏臭氧层的化合物. 这些发现有助于解释以前未计入的排放量,影响大气预算.
科学领域:
- 大气中的化学成分
- 生物地质化学生物地质化学
- 环境科学环境科学
背景情况:
- 甲基化物是破坏臭氧层的的主要天然来源,对大气中的含量作出了重大贡献.
- 在工业化前,大气中的含量很可能更高,因为没有化碳等人为来源.
- 现有的模型显示全球甲基化物预算存在缺口,表明未确定的排放来源.
研究的目的:
- 识别和量化以前未知的甲基化物排放的自然来源.
- 调查特定热带植物在甲基化物生产中的作用.
- 改进对全球甲基化物预算及其对大气的影响的理解.
主要方法:
- 现场观察常见热带植物 (包括和Dipterocarpaceae) 的甲基化物排放情况.
- 量化每小时每单位干叶质量的排放率.
- 估计来自特定地区的甲基化物流量,例如东南亚.
主要成果:
- 从某些热带植物中观察到大量的甲基化物排放,排放量在0.1至3.7μg/g干叶/小时之间.
- 仅东南亚的Dipterocarpaceae的甲基化物流量估计为每年0.91 Tg.
- 这些植物排放占当前大气预算中缺少的甲基化物来源的很大一部分.
结论:
- 热带植物,特别是和Dipterocarpaceae,是大气中甲基化物的重要贡献者.
- 这些发现有助于解决全球甲基化物预算中的差异.
- 未来热带森林砍伐的变化可能会改变天然化合物来源,过去的丰富可能影响了古代的大气.
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