| A study of the continuous precipitation in Guiyang has been taken during October 30 and November 7. The results showed that the range of pH was between 3.65 and 7.20, and volume-weighted mean was 4.24. SO2-4was the main anion and volume-weighted mean was 119.06 μeq·L-1, accounting for 80.63% of total anions. While Ca2+ was the main cation and volume-weighted mean was 48.87 μeq·L-1, accounting for 48.16% of total cation and NH+4was 38.38 μeq·L-1, 37.82%. Good correlations between Mg2+, Ca2+, NH4+ and SO2-4are observed, which may exist as MgSO4,CaSO4and (NH4)2SO4in the rainwater in Guiyang City. Different ions of the atmosphere had different scavenged ways and rate in the precipitation process. In the initial stage of precipitation, the ions such as Mg2+, which were rich in coarse particles, were quickly removed from atmosphere. However the ions such as NH+4and SO2-4, which were rich in fine particles, could remain in the atmosphere for a longer time. |
