在瑞典亚北极流域的空气表面交换甲氧二
Terry F Bidleman1, Kathleen Agosta1, Emma Shipley2
1Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden.
The Science of the total environment
|July 18, 2024
概括
甲氧 (HMBs) 在南极湖泊和流域中进行空气-表面交换. 2022年9月的数据显示,HMBs几乎处于稳定状态,净沉积到湖中,混合挥发/从土壤沉积.
科学领域:
- 环境化学环境化学
- 大气科学 大气科学
- 生态毒理学 生态毒理学
背景情况:
- 甲基 (HMBs) 是天然存在的和具有环境相关性的人为化合物.
- 它们的挥发性和水溶性有助于它们与水生和陆生生态系统进行大气交换.
- 了解HMB的环境命运对于评估生态风险至关重要.
研究的目的:
- 调查南极湖泊和流域中特定HMB (化和化二氧化) 的空气-表面交换.
- 量化HMBs在大气,湖水和土壤之间的净流量.
- 评估研究的流域内HMBs的平稳状态条件.
主要方法:
- 使用固相提取方法从水样中分离HMB.
- 从垃圾/土壤样本中用溶剂提取HMB.
- 使用毛细管气体染色学-四极质谱学量化HMBs.
- 应用双薄膜气体交换模型来估计空气-表面流量.
主要成果:
- 在湖泊和溪流水中发现的HMB包括1,2,4,5-四-3,6-二甲 (DAME),2,4-二甲 (DiBA),2,4,6-三甲 (TriBA) 和四甲 (TeCV).
- 在亚北极的垃圾/土壤中发现了DAME和2,3,5,6-四四甲基 (DA).
- 观察到DiBA,TriBA和DAME的净沉积到湖中,占湖泊库存的4-7%.
- 与垃圾/土壤的HMB交换显示出不同的结果,在大多数地点都有显著的净挥发.
结论:
- 在2022年9月,Torneträsk流域在HMB交易方面接近稳定状态.
- 预计HMB交易的季节性变化需要进一步调查.
- 这项研究提供了有关HMBs在南极生态系统中的环境行为的宝贵数据.
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