| Texto completo | |
| Autor(es): |
Seymore, Jackson
;
Felix, J. David
;
Abdulla, Hussain
;
Bergmann, Daniela
;
Campos, M. Lucia A. M.
;
Florencio, Jacques
Número total de Autores: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | ACS EARTH AND SPACE CHEMISTRY; v. 7, n. 10, p. 18-pg., 2023-10-04. |
| Resumo | |
Rainwater dissolved organic matter (DOM) is a complex mixture of organic compounds, the composition of which remains largely unknown. This is despite its central role in a host of fundamentally important atmospheric processes (e.g., aerosol hygroscopicity, light absorption, etc.). This work illustrates the molecular composition of DOM in rainwater collected from February 2020 to June 2021 (n = 32 of rain samples) in Ribeir & atilde;o Preto, SP (21 degrees 09 ' 41.0 '' S 47 degrees 51 ' 29.9 '' W), using complementary methods of traditional ion chromatography and Orbitrap mass spectrometry with novel statistical analysis. This approach provides a detailed, ultrahigh-resolution, high-throughput method for rainwater DOM investigations, demonstrated here with ultra performance liquid chromatography coupled with Orbitrap mass spectrometer, positive-mode electrospray ionization. Using this method, 2788 unique molecular formulas were identified over the mass-to-charge ratio range of 80-800. DOM character is revealed to be largely influenced by organic nitrogen, as 86.0% (2397 species) of unique organic compounds identified contained nitrogen, many likely peptides, or amino acid derivatives. Recent pandemic-related influences on anthropogenic activity in Ribeir & atilde;o Preto, SP region, are observed through variations in rainwater DOM characteristics. Rainwater prior to the COVID-19 pandemic's emergence in Brazil is distinct from reduced anthropogenic activity rainwater in the DOM character & horbar;seen as an increase in primary compounds and amino acid contribution, wider range of O/C ratios, and absence of atmospheric NOx-related CHON oligomers & horbar;and a major ion content & horbar;showing a reduction in sulfate, nitrate, potassium, and formate. Clustering analysis shows that these distinctions are mostly driven by changes in anthropogenic reactive nitrogen emissions as well as seasonal influences. (AU) | |
| Processo FAPESP: | 18/16554-9 - Avaliando o impacto das emissões atmosféricas relacionadas à produção e uso de etanol na perspectiva das atuais políticas públicas de biocombustíveis |
| Beneficiário: | Maria Lúcia Arruda de Moura Campos |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |