Role of desert aerosol in metal fluxes in the Mediterranean area

doi:10.1016/S0045-6535(99)00105-8

Chemosphere

Volume 39, Issue 2, July 1999, Pages 229-246

https://doi.org/10.1016/S0045-6535(99)00105-8 Get rights and content

Abstract

The chemical composition of aerosols and precipitation collected over Sardinia primarily reflect Saharan and European inputs. European background aerosols in Sardinia show a 3- to 25-fold decrease in EF_crust values for Cd, Zn, Pb, and Cr compared with coastal stations in the Western Mediterranean. Partitioning of total atmospheric deposition between soluble and insoluble phases shows that Al, Si, Fe and Pb originating from the atmosphere are mostly in an insoluble form. For Ca, Cd and Cr metals, the dissolved fraction represents 50–90% of the total input. Aerosol dissolution experiments performed at particle concentrations ranging from 3 to 300 mg l⁻¹ show that Cd and Pb have low solubilities at high mass particle concentrations. The solubility of Pb increases with EF_crust values and the finest grain-size of the aerosols (<1μmm), and is also affected by pH. Dissolution of Al and Fe decreases significantly from 30% (13% for Fe) at aerosol loads lower than 5 mg l⁻¹ to less than 1 % for both metals at total aerosol concentrations greater than 100 mg l⁻¹. The fluxes (dry + wet) of metals in Sardinia show that ∼ 30% of the Cd and Pb to more than 80% of the Fe and Al come from the Sahara.

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Role of desert aerosol in metal fluxes in the Mediterranean area

Abstract

Deep-Sea Res. II

Deep-Sea Research II

Atmospheric Environment

Science of Total Environment

Atmospheric Environment

Marine Chemistry

Geochimica et Cosmochimica Acta

Atmospheric Environment

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Geochimica et Cosmochimica Acta

Atmospheric Environment

The atmospheric input of trace species to the world oceans

Global Biogeochem. Cycl.

Saharan dust input to the Western Mediterranean: an eleven years record in Corsica

Present-day transport and deposition patterns of African dusts to the North-Western Mediterranean

A model for Saharan dust transport

Journal of Climate and Applied Meteorology

Saharan dust transport over the North Atlantic ocean and Mediterranean: an overview

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Atmospheric transport of iron and its deposition in the ocean

Limnology and Oceanography

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Global Biogeochemical Cycles

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Tellus

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J. Atmos. Chem.