To study the characteristics of precipitation in eastern China, an automatic sampler was used to collect rainwater samples from 19 precipitation events at Mangdang Mountain, Nanping City, Fujiang Province, in the spri...To study the characteristics of precipitation in eastern China, an automatic sampler was used to collect rainwater samples from 19 precipitation events at Mangdang Mountain, Nanping City, Fujiang Province, in the spring of 2009. We used ion chromatography to analyze the ionic components and concentrations, and inductively coupled plasma mass spectrometry （ICP-MS） to analyze dement compositions and contents. The results demonstrated remarkable acidic characteristics： in more than 80% of precipitation events the pH was less than 5.6, with an average of 4.81. Mass concentration results showed SO42- was the main anionic component （36.2% of the total anion mass）, while N/-/4＋ was the main cationic component （47.7% of the total cation mass） and main ion for acidity neutralization in the rainwater. Organic acid content accounted for 30.9% of total anion mass. The main trace metals were Ca, K, and Na. The S042-/N03- ratio was 1.4, indicating that precipitation in this region was influenced by complex air pollution - the product of individual coal-burning combined with vehicle exhaust pollution. Correlation analysis of the chemical composition of the precipitation indicated that acidity in this region was determined by a combination of all acidic and neutralization ions rather than any single ion component. The results also showed that Na＋ and C1- contributions were mainly by seawater; Mg2＋ by seawater and crustal materials; the NH4＋, K~, Ca2＋, NO3- and SO42- by anthropogenic sources; the trace metals were from the Earth＇s crust; and organic acids were potentially from combustion of biomass.展开更多
基金supported by the National Basic Research Program (973) of China (No. 2005CB422204)
文摘To study the characteristics of precipitation in eastern China, an automatic sampler was used to collect rainwater samples from 19 precipitation events at Mangdang Mountain, Nanping City, Fujiang Province, in the spring of 2009. We used ion chromatography to analyze the ionic components and concentrations, and inductively coupled plasma mass spectrometry （ICP-MS） to analyze dement compositions and contents. The results demonstrated remarkable acidic characteristics： in more than 80% of precipitation events the pH was less than 5.6, with an average of 4.81. Mass concentration results showed SO42- was the main anionic component （36.2% of the total anion mass）, while N/-/4＋ was the main cationic component （47.7% of the total cation mass） and main ion for acidity neutralization in the rainwater. Organic acid content accounted for 30.9% of total anion mass. The main trace metals were Ca, K, and Na. The S042-/N03- ratio was 1.4, indicating that precipitation in this region was influenced by complex air pollution - the product of individual coal-burning combined with vehicle exhaust pollution. Correlation analysis of the chemical composition of the precipitation indicated that acidity in this region was determined by a combination of all acidic and neutralization ions rather than any single ion component. The results also showed that Na＋ and C1- contributions were mainly by seawater; Mg2＋ by seawater and crustal materials; the NH4＋, K~, Ca2＋, NO3- and SO42- by anthropogenic sources; the trace metals were from the Earth＇s crust; and organic acids were potentially from combustion of biomass.
