Photoinduced production of substances with humic-like fluorescence, upon irradiation of water samples from Alpine lakes
| Autor: | Luca Carena, Yiqun Wang, Sasho Gligorovski, Silvia Berto, Stéphane Mounier, Davide Vione |
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| Přispěvatelé: | Dipartimento di Chimica, Università di Torino, State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2023 |
| Předmět: |
Environmental Engineering
Photochemistry Health Toxicology and Mutagenesis Public Health Environmental and Occupational Health Aquagenic organic matter General Medicine General Chemistry Pollution Fluorescence PARAFAC analysis Spectral slope [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry [CHIM.ANAL]Chemical Sciences/Analytical chemistry Environmental Chemistry Aquagenic organic matter Photochemistry Fluorescence PARAFAC analysis Spectral slope |
| Zdroj: | Chemosphere Chemosphere, 2023, 319, pp.137972. ⟨10.1016/j.chemosphere.2023.137972⟩ |
| ISSN: | 0045-6535 |
| Popis: | International audience; Evidence is here provided that irradiation of some lake water samples can trigger the formation of fluorophores with humic-like properties, at the same time increasing water absorbance. This phenomenon is the opposite of photobleaching, which is often observed when natural waters are irradiated. Photogeneration of humic-like compounds can be highlighted in water samples where the initial fluorescence signal of humic substances is low, so that photobleaching is minimised. Samples that are most likely to show photoinduced formation of humic-like fluorophores are in fact characterised by high values of protein-like vs. humic-like contribution ratios to fluorescence, as evidenced by parallel factor (PARAFAC) analysis. Mountain lakes in late summer appear to be suitable candidates to highlight the described phenomenon. In some cases, lake-water irradiation caused a decrease in the spectral slope of the absorbance that, together with increasing absorbance values, is consistent with an increase in molecular mass and aromaticity of organic matter. The absorbance increase triggered by irradiation might play a role in screening biologically harmful UV radiation, in mountain environments that would otherwise be characterised by very clear water, where UV light can be easily transmitted along the water column. |
| Databáze: | OpenAIRE |
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