植物对氧化有机微量气体进行有效的大气清洁
1National Center for Atmospheric Research, Boulder, CO 80301, USA. tomkarl@ucar.edu
Science (New York, N.Y.)
|October 23, 2010
概括
生物圈对大气中的挥发性有机化合物 (VOC) 产生重大影响. 这项研究揭示了森林中氧化的VOC干沉积量比以前认为的要高,影响大气化学.
科学领域:
- 大气化学和生态学
- 生物地质化学循环是什么
- 环境科学环境科学
背景情况:
- 生物圈是大气中非甲挥发性有机化合物 (VOC) 的主要来源和沉积点.
- 大气中挥发性有机物的去除是通过气相反应,表面沉积或氧化成CO和CO2发生的.
- 目前的模型可能低估了陆地生态系统中氧化VOC干沉积的作用.
研究的目的:
- 量化生态系统规模的氧化VOCs的干沉积流在叶森林.
- 研究植被吸收氧化的VOC的机制,包括酶过程和遗传反应.
- 改善氧化VOC干沉积在全球大气化学模型中的表现.
主要方法:
- 进行了生态系统规模的流量测量,以确定干沉积率.
- 实验室实验评估了植物对VOC暴露和压力的反应 (酶转化,基因表达).
- 一个修订的氧化VOC吸收方案被纳入了全球化学运输模型.
主要成果:
- 在落叶生态系统中氧化VOC的干沉积量远远大于以前的估计.
- 实验室发现表明,高效的酶转化和压力诱导的上调调节增强VOC吸收的基因.
- 修订后的模型预测了氧化VOC的年度干沉积流的显著区域变化.
结论:
- 植被在通过干燥沉积去除氧化VOC中发挥的作用比目前认为的要大得多.
- 植物生理反应,包括酶活性和遗传调节,对于VOC吸收至关重要.
- 纳入这些发现的更新模型对于准确预测大气组成和沉积模式是必要的.
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