Study of chemical composition in wet atmospheric precipitation in Eshidiya area, Jordan

Abstract

The present study investigated the chemical composition of wet atmospheric precipitation samples in the Eshidiya area in south Jordan. The samples were analyzed from October 2003 to May 2004. All samples were analyzed for major ions (Cl −, NO 3 - , HCO 3 - , SO 4 2 - , Na +, K +, Ca 2+, Mg 2+ and NH 4 + ) and trace metals (Cd, Cu, Pb, Zn, Fe and Ni). The highest concentration of elements is observed at the beginning of the rainfall season when large amounts of dust accumulate in the atmosphere scavenged by rain. The daily sample pH values ranged from 5.33 to 7.90 with a median value of 6.65±0.68. Rain water quality is characterized by low salinity and neutralized pH. High values of pH were attributed to the neutralization by natural alkaline local dusts which contain a large fraction of calcite and dolomite. The major ions in rainwater samples showed high Ca 2+, HCO 3 - , SO 4 2 - , Cl − and Mg 2+ concentrations. For trace metals, the study identified that the origin of these metals from local anthropogenic activities (from soil and phosphate mine, heating activities during the cold period of year (January to April) and the anthropogenic activities. In general, the results of this study suggest that the rainwater chemistry is strongly influenced by natural sources rather than anthropogenic and marine sources.