Wet deposition (WD) and Dry deposition (DD) samples were collected during a period of 4 year (2006 to 2009), at four different sites representing different surroundings around Pune city in southwest India. The samples were collected on a daily basis for WD and weekly basis for DD. These samples were analyzed for major ionic components e.g., Cl − , NO 3 − , SO 4 2− , Na + , K + , NH 4 + , Ca 2+ and Mg 2+ . Both the WD and DD were alkaline (pH > 5.6) at all the four sites. The WD fluxes of all

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... ionic components were higher than the DD fluxes, except at the traffic junction Swargate, where majority of the species appeared with much higher DD fluxes than WD fluxes (68% for NO 3 − , 63% for Ca 2+ , 60% for Mg 2+ , 57% for K + ). WD flux of NH 4 + is higher (64-80%) than the DD flux at three locations and slightly lower (48%) at a high altitude location. In case of sea salt (Na and Cl), WD fluxes were higher (63-90%) than the DD fluxes at all the four locations. The dominant ion in DD was NO 3 − at Pashan (semi-urban) and Sinhagad (high altitude), Ca 2+ at Swargate (traffic junction) and SO 4 2− at Bhosari (industrial). The difference in deposition fluxes between the four sites was attributed to the effect of the local sources. Deposition velocities of SO 4 2− and NH 4 + were < 1 cm/s while Ca 2+ , Mg 2+ , Na + , K + , NO 3 − , and Cl − exhibited deposition velocities ≥ 1 cm/s. At one of the sites Pashan, where the earlier data is available; DD rates showed increase in all the chemical components, except for NH 4 + after a period of about 2 decades.