제주시 지역 빗물의 특성 및 분석 데이타의 정밀도에 관한 연구 = Characteristics of Rainwater in Cheju City and Precison of Its Analytical Data

다국어 초록 (Multilingual Abstract)

The precipitation samples were collected at a site in Cheju National University and investigated for the major ion components of them during the period of October, 1996 to May, 1997. During this period, the volume-weighted average value of pH was 5.09 and that of electric conductivity was 16.61μS/㎝, and the concentrations of ions were shown in the order of SO₄²?> Cl?> NO₃?>Na?> NH₄?> Ca²?> K?> Mg²?.
For the precision of the analytical data, the correlation coefficient between the sum of the cation equivalent concentrations and that of the anion equivalent concentrations showed r²=0.8745 (r=0.940), and the correlation coefficient between the measured conductivity and the calculated conductivity was r²=0.9898, showing quite satisfactory agreement each other. Also, the correlation coefficient between the acid fraction from the equivalent concentrations of each ion and that from the measured pH and electric conductivity showed r²=0.9107.
In the investigations of sea-salt effect, the enrichment factor of SO₄²?, Ca²?, K? was 9.1, 12.8, and 8.2, respectively, showing that most of these were coming to the air by the other factors rather than from seawater. On the other hand, it was found that the Cl? and Mg²? were mostly due to the origin of seawater. In the case of the effect of soil particulates, the enrichment factors of SO₄²?, Cl?, NO₃?, and NH₄? showed quite high values indicating suspending in the air through the other factors, however, some of Na?? and Mg²? and most of K? were found mainly due to the soil particulates. Moreover, for the effect on the pH of rainwater, the calculated neutralization factors of NH₄?, Ca²?, and Mg²? were 0.415, 0.274, and 0.101, respectively. It has shown that the hydrogen ions in the rain of Cheju city were neutralized about 52% by NH₃, and the Ca²? and Mg²? have neutralized them about 35%, and 13%
respectively.