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The ionic composition of 55 aerosol samples and 31 precipitation events collected in a coastal site in southern Sardinia (Capo Carbonara, 39 degrees 06' N; 09 degrees 31' E) were compared. The samples were collected during one year period (Oct'90/0ct'91) and showed high variability in composition according to meteorological conditions. Rain and soluble part of aerosol showed a strikingly similar ionic composition: most significant anions were chlorine and sulphate, and sodium is the principal cations, followed by magnesium and calcium. The acid events are associated with N-NW trajectories (anthropogenic influxes from N. Europe) with avg. pH=4.65, non sea salt (nss) Ca=60 mu eq/l and NO3/nssSO4=0.6. Southern precipitations are influenced by Saharan dust alkaline effects, with avg. pH=6.75, Ca-nss=271 mu eq/l and NO3/nssSO4=0.4. Na/Cl ratio in rain is similar to sea water (0.87), whilst in aerosols there is a Cl loss (Na/Cl=1.10), probably due to reaction with nitric acid. Total fluxes of Ca, Mg, NO3 and SO4 were 104, 9, 64 and 113 mu g/cm(2), and wet deposition exceeded (65-90%) dry deposition. Scavenging ratios (SR) as defined by the equation: SR=[(Ci)rain/(Ci)air]*d, (d=1200g/m(3)) were calculated, using geometric means (Ci) of precipitation and aerosols collected concurrently during the period (a total of 23 samples). The SR values are Ca=3400, Cl=2400, Na, K, SO4=1700, Mg=1000 and NO3=750. These numbers could be useful to infer total fluxes by using simply rainwater ionic composition in Mediterranean semi-arid sites like Sardinia.