Relationship Between Atmospheric Dissolved Deposition and Mineral Dust Deposition in French Forests

• Published in: Water, Air, & Soil Pollution
• Main Authors: Lequy, Emeline, Nicolas, Manuel, Conil, Sébastien, Turpault, Marie-Pierre
• Other Authors: Unité de recherche Biogéochimie des Ecosystèmes Forestiers (BEF), Institut National de la Recherche Agronomique (INRA), Observ Perenne Environm, DRD Observat Surveillance, Agence Nationale pour la Gestion des Déchets Radioactifs (ANDRA), Direct Tech & Commerciale Boi, Partenaires INRAE, Andra; GIP ECOFOR
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: Atmospheric deposition; Atmospheric mineral particles; Proxy; Calcium; ICE CORE; FRANCE; PRECIPITATION; CHEMISTRY; RAINWATER; EPISODE; SAHARAN DUST; CHEMICAL-COMPOSITION; INPUT; TRANSPORT; [SDV]Life Sciences [q-bio]; ice core
• Online Access: https://hal.inrae.fr/hal-02651883; https://doi.org/10.1007/s11270-013-1680-4

International audience Calcium dissolved deposition shows an unusual spatial structure in France, probably due to the contribution of southern air masses from Mediterranean Sea and Saharan desert. These masses are often loaded with terrigenous particles that contain carbonates. However, no precise relationship has been quantified between dissolved Ca and mineral dust deposition (MDD). The database of the French network RENECOFOR, gathering atmospheric deposition <0.45 mu m in 27 sites near forests during 18 years, was used to determine the non-sea-salt atmospheric deposition over France. This study (1) explores the relationship between dissolved components to decipher their origin in atmospheric deposition nearby forests and (2) tests the use of dissolved Ca and Mg as proxies for MDD. In the RENECOFOR database, non-sea-salt Ca (nssCa) preferentially deposited between May and August. MDD observed in RENECOFOR was synchronic with high nssCa deposition, particularly in June 2008, when air mass highly loaded with Saharan dust covered France. The dissolution of this mineral dust likely contributed to the nssCa deposition of this period and suggested a relationship between the depositions of nssCa and MDD. Then, MDD was specifically sampled with dissolved deposition in four sampling sites. Encouraging relationships were found between MDD and the depositions of nssMg and nssCa, suggesting that the latter could be used as a proxy for MDD in regions where it is not monitored, and in a retrospective approach in order to calculate nutrient fluxes.