Chemical characteristics of precipitation and wet deposition of major ions in Liaozhong County of Liaoning Province,Northeast China

The chemical characteristics of precipitation were analyzed based on the chemical composition of principal ionic within acid rain (from February 2007 to January 2008) of Liaozhong Meteorological Station located in Malong Village in Liaozhong County of Northeast China, meteorological conditions on the corresponding period ground, and variation of several air pollutants concentration. The results indicated that: (1) The precipitation average pH value of all samples was 4.76; the frequency of acid rain during the observation period was 70.7%; the frequency was 82.8% in summer and autumn. (2) In the chemical composition of precipitation, the primary anions were SO₄^2- and NO₃^-; the primary cations were NH₄⁺ and Ca²⁺. (3) All concentration of anions was higher in summer and winter, but relatively low in spring and autumn. This showed that the relationship between regional rainfall acidification and pollution was not significant. (4) Rainwater acidity and nearly floor gaseous pollution concentration were different from each other, and pH and NO_x, CO, NO₂ and O₃ concentrations showed significant negative correlation, but was not obvious with SO₂ concentration. However, the pH and alkaline pollutants, such as particulate, was positively correlative.