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美国野火造成的颗粒物Pb排放因子
Amara L Holder1, Venkatesh Rao2, Kasey Kovalcik1
1U.S. Environmental Protection Agency, Office of Research and Development, 109 T. W. Alexander Dr., Durham, NC 27709.
概括
野火会在细颗粒物 (PM2.5) 中排放 (Pb). 大多数留在灰中,排放的不到10%,随生物质度而变化.
科学领域:
- 大气科学 大气科学
- 环境化学环境化学
- 生态生态学 生态生态学
背景情况:
- 在美国,野火和农业火灾是大气细颗粒物 (PM2.5) 的主要来源.
- 虽然火灾排放主要是碳的,但火灾排放也含有微量金属,如 (Pb),这是受监管的污染物.
- 由于大量的PM2.5排放,火灾可以大大增加大气中的含量.
研究的目的:
- 量化生物质中的 (Pb) 度,灰和来自野火的PM2.5.
- 为了计算来自美国各种生物质类型的的排放因子.
- 为了提高大气中火灾导致的排放估计的准确性.
主要方法:
- 使用了在规定的火灾附近的现场测量和实验室模拟.
- 在未燃烧的生物质,灰/残留物和PM2.5.5中测量了度.
- 美国不同地区的不同生物质类型的排放因子被计算出来.
主要成果:
- 大多数来自生物质的 (Pb) 在燃烧后留在灰/残留物中.
- 在总中,微粒颗粒物 (PM2.5) 的排放量不到10%.
- 排放的分数取决于生物质中的初始度.
结论:
- 野火会释放出,但大部分会留在灰中,PM2.5.5中的小部分 (<10%) 在灰中.
- 测量的排放因子低于一些文献值,这表明测量的潜在不确定性.
- 准确的排放因子对于了解污染至关重要,特别是随着火灾频率的增加.
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