Geochemistry of natural and anthropogenic fall-out (aerosol and precipitation) collected in NW Mediterranean: two different multivariate statistical approaches

The chemical characteristics of the mineral fractions of aerosol and precipitation collected in Sardinia (NW Mediterranean) are highlighted by means of two multivariate statistical approaches. Two different combinations of classification and statistical methods for geochemical data are presented. It is shown that the application of cluster analysis subsequent to Q-Factor analysis better distinguishes among Saharan dust, Background pollution (Europe-Mediterranean) and Local aerosol from various source regions (Sardinia). Conversely, the application of simple cluster analysis was able to distinguish only between aerosols and precipitation particles, without assigning the sources (local or distant) to the aerosol. This method also highlighted the fact that crust-enriched precipitation is similar to desert-derived aerosol. Major elements (Al, Na) and trace metal (Pb) turn out to be the most discriminating elements of the analysed data set. Independent use of mineralogical, granulometric and meteorological data confirmed the results derived from the statistical methods employed

Role of desert aerosol in metal fluxes in the Mediterranean area.

Aerosols and precipitations collected over Sardinia are mainly controlled by two end-members: Saharan and European. European background aerosols in Sardinia show a 3 to 25-fold decrease in EFcrust values for Cd, Zn, Pb, and Cr compared with coastal stations in the Western Mediterranean. Partitioning of total atmospheric deposition between the soluble and the insoluble phases shows that Al, Si, Fe and Pb originating from the atmosphere are mostly in the insoluble form. For Ca, Cd, 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 Cd and Pb exhibiting low solubility at the high mass particle concentration. Solubility of Pb increases with the EFcrust values and the finest grain-size of the aerosols (<1µm), and is less affected by pH. Al and Fe solubilities appear to be mainly controlled by the particulate load. Dissolution of both metals 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 50 mg l-1, which are encountered during Saharan transport. Fluxes (dry +wet) of metals at Sardinia show that ~ 30% for Cd and Pb, to more than 80 % for Fe and Al are due to Saharan contribution

Managing household waste in Ireland: behavioural parameters and policy options

Formulating efficient waste management policy requires data on market conditions. Data on household waste management behaviour in Ireland is scarce, and policy making could benefit from improved data and market analysis. In this paper we estimate models of household waste management behaviour in Ireland using econometrics and simple comparison of average effects, but we find that some important parameters cannot be obtained robustly using existing aggregate data. Drawing upon international literature in order to complete our assumptions, we apply a simulation model to illustrate the likely effects of some current policy options. We show that increases in the landfill levy are likely to have little effect on household behaviour if pay-by-use tariffs are not fully implemented, and we find that while introducing additional bins for segregated compostable waste may divert significant quantities of such waste, they are more effective in cities than in rural areas. We also highlight key shortcomings of the available data.municipal solid waste, household waste management, Ireland,