Chemical Composition of Water Soluble Inorganic Species in Precipitation at Shihwa Basin, Korea

Atmosphere

Seung-Myung Park³  Beom-Keun Seo²  Gangwoong Lee⁴  Sung-Hyun Kahng¹  Yu Woon Jang⁴ 

[1] Korea Institute of Ocean Science and Technology, 426-744 Ansan, Korea; E-Mail:;National Institute of Meteorological Research, 697-845 Seogwipo, Korea; E-Mail:;National Institute of Environmental Research, 404-708 Inchon, Korea; E-Mail:;Department of Environmental Science, Hankuk University of Foreign Studies, 449-791 Yongin, Korea; E-Mail:

关键词: acid precipitation;    nitrate;    precipitation;    sulfate;    Korea;    pH;   

DOI  :  10.3390/atmos6060732

来源: mdpi

【 摘 要 】

Weekly rain samples were collected in coastal areas of the Shihwa Basin (Korea) from June 2000 to November 2007. The study region includes industrial, rural, and agricultural areas. Wet precipitation was analyzed for conductivity, pH, Cl⁻, NO₃⁻, SO₄²⁻, Na⁺, K⁺, Mg²⁺, NH₄⁺, and Ca²⁺. The major components of precipitation in the Shihwa Basin were NH₄⁺, volume-weighted mean (VWM) of 44.6 µeq∙L⁻¹, representing 43% of all cations, and SO₄²⁻, with the highest concentration among the anions (55%) at all stations. The pH ranged from 3.4 to 7.7 with a VMM of 4.84. H⁺ was weakly but positively correlated with SO₄²⁻ (r = 0.39, p < 0.001) and NO₃⁻ (r = 0.38, p < 0.001). About 66% of the acidity was neutralized by NH₄⁺ and Ca²⁺. The Cl⁻/Na⁺ ratio of the precipitation was 37% higher than seawater Cl⁻/Na⁺. The high SO₄²⁻/NO₃⁻ ratio of 2.3 is attributed to the influence of the surrounding industrial sources. Results from positive matrix factorization showed that the precipitation chemistry in Shihwa Basin was influenced by secondary nitrate and sulfate (41% ± 1.1%), followed by sea salt and Asian dust, contributing 23% ± 3.9% and 17% ± 0.2%, respectively. In this study, the annual trends of SO₄²⁻ and NO₃⁻ (p < 0.05) increased, different from the trends in some locations, due to the influence of the expanding power generating facilities located in the upwind area. The increasing trends of SO₄²⁻ and NO₃⁻ in the study region have important implications for reducing air pollution in accordance with national energy policy.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.