城市和郊区的黑色和棕色碳度存在显著差异
Admir Créso Targino1, Fabian Leonardo Moreno1, Patricia Krecl1
1Graduate Program in Environmental Engineering, Federal University of Technology, Av. Pioneiros 3131, 86036-370, Londrina, PR, Brazil.
Heliyon
|July 31, 2023
概括
吸光碳粒子 (LAC),包括棕色碳 (BrC) 和黑碳 (BC),对健康和气候产生影响. 生物质燃烧在郊区的LAC中起着显著的作用,而城市中心显示出复杂的污染物混合.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 公共卫生 公共卫生
背景情况:
- 吸光碳质颗粒 (LAC) 对人类健康和环境构成风险.
- 了解LAC的来源和行为对于空气质量管理至关重要.
研究的目的:
- 调查城市和郊区地区棕色碳 (BrC) 和黑色碳 (BC) 度的时间变化.
- 确定巴西中型城市中LAC的主要来源和特征.
主要方法:
- 在两个不同的城市地点监测370 nm (BrC) 和880 nm (BC) 的LAC度.
- 分析风力模式和安格斯特罗姆吸收指数 (Å370/880) 以区分污染源.
- 与交通量和气象条件相关的LAC水平的相关性.
主要成果:
- 城市交通显著影响了市中心的LAC水平,峰值与交通量和公交车站靠近程度有关.
- 郊区网站显示了统一的白天模式,但在LAC显著的晚上增加,归因于生物质和废物燃烧.
- 棕色碳 (BrC) 度往往超过黑色碳 (BC),安格斯特罗姆指数表明生物质燃烧是郊区的主要来源.
结论:
- 生物质燃烧是 LAC 在郊区环境中的主要贡献者.
- 在城市中心,LAC粒子是来自各种来源的黑碳和棕色碳的混合物,包括化石燃料和生物质.
- 有效的空气质量战略必须解决不仅仅是车辆交通之外的多个LAC来源.
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