• Asian Journal of Atmospheric Environment
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• 제8권2호
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• pp.69-80
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• 2014

It is often assumed that atmospheric observations at remote sites represent long-range transport of airborne material, and local influences are overlooked. We evaluated the impact of local input on the rainwater composition at Gosan Station, a strategic site for monitoring the continental outflow from Asia. We analyzed a 14-year record of rainwater chemical composition archived by the Korea Meteorological Administration and detected local terrestrial contribution for nitrate, sulfate and ammonium. We also measured the chemical composition of rainwater sampled simultaneously at multiple locations within the premises of the Gosan Station, from which local influence with meter-scale spatial heterogeneity could be discerned. We estimate that the local input accounted for at least ~10% of the wet deposition of nitrogen and ~12% of the wet deposition of sulfur during the 14 years. This highlights the significance of the local influence, which should be carefully assessed when interpreting atmospheric observations at this site.

• 한국대기환경학회지
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• 제29권6호
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• pp.818-829
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• 2013

The collection of rainwater samples was made at Jeju area during 2009~2010, and the major ionic species were analyzed. In the comparison of ion balance, conductivity, and acid fraction for the validation of analytical data, the correlation coefficients showed a good linear relationship within the range of 0.966~0.990. The volume-weighted mean pH and electric conductivity were 4.9 and $17.8{\mu}S/cm$, respectively, at the Jeju area. The volume-weighted mean concentrations of ionic species in rainwater were in the order of $Cl^-$ > $Na^+$ > $nss-SO_4{^{2-}}$ > $NH_4{^+}$ > $NO_3{^-}$ > $Mg^{2+}$ > $H^+$ > $nss-Ca^{2+}$ > $HCOO^-$ > $K^+$ > $PO_4{^{3-}}$ > $CH_3COO^-$ > $NO_2{^-}$ > $F^-$ > $HCO_3{^-}$ > $CH_3SO_3{^-}$. The ionic strength of rainwater was $0.26{\pm}0.21$ mM during the study period. The composition ratios of ionic species were such as 50.1% for the marine sources ($Na^+$, $Mg^{2+}$, $Cl^-$), 30.9% for the anthropogenic sources ($NH_4{^+}$, $nss-SO_4{^{2-}}$, $NO_3{^-}$), and 4.7% for the soil source ($nss-Ca^{2+}$), and 3.1% for organic acids ($HCOO^-$, $CH_3COO^-$). From the seasonal comparison, the concentrations of $NO_3{^-}$, $nss-Ca^{2+}$, and $nss-SO_4{^{2-}}$ increased in winter and spring seasons, indicating a reasonable possibility of long range transport from Asia continent. Especially, the acidifying contributions by major inorganic acids ($nss-SO_4{^{2-}}$ and $NO_3{^-}$) and organic acids ($HCOO^-$ and $CH_3COO^-$) were 87.6% and 12.4%, respectively. In comparison by sectional inflow pathway of air mass during the rainy sampling days, the concentrations of $nss-SO_4{^{2-}}$ and $NO_3{^-}$ were relatively high when the air mass was moved from the China continent into Jeju area.

• 한국환경농학회지
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• 제19권1호
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• pp.72-74
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• 2000

우리나라 강우의 산성도 중화에 미치는 $NH_4\;^+$ 및 $Ca^{2+}$ 영향을 평가하기 위하여 '98년 5월부터 10월까지 6개월 동안 수원, 안성 및 태안지역에 내린 강우의 주요 이온들의 함량을 조사한 결과, $[H^+]+[NH_4\;^+]+[Ca^{2+}]$의 역대수값으로 계산되는 이론적 산성도는 측정된 pH값에 비해 각각 7.9, 8.7 및 6.5배 높았다. 또한 빗물의 산성도 중화에는 $NH_4\;^+$가 $Ca^{2+}$ 보다 기여도가 컸으며, 지역별 $Ca^{2+}$의 영향은 수원지역이 안성 및 태안지역에 비해 크게 나타났다.

• Advances in environmental research
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• 제2권2호
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• pp.99-118
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• 2013

Rainwater runoff has been identified as a significant source of contaminants having tremendous impact on the receiving aquatic environment. In the present study, trace element transport by the surface runoff in the predominantly urban catchment of Guwahati city, India was monitored with a view to determine the chemical denudation rates of the land surface. A number of trace metals, namely Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn were measured in the runoff after 70 major rain events within the city. Cadmium was found to be the least abundant metal and Iron was the most abundant metal in the runoff. The results are interpreted on the basis of temporal and spatial variations in their concentrations. These variations are quite large in some of the events and reflect changes in the local environmental setting, differences in water utilization, variations in runoff volume, gradient and quality.

• 한국환경과학회지
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• 제5권6호
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• pp.739-748
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• 1996

This study was carried out to investigate the chemical characteristics ol rainwater sampled in Cheju City from July 1994 to June 1996. Concentrations of major ions (Cl-,$SO_4^{2-}$, NO_3^-$, $Na^+$, $K^+$, Ca^{2+}$, $Mg^{2+}$ and NH_4^+$) were determined. The pH of rainwater, calculated from the volume weighted H+ concentration, was found to be 5.61, indicating extensive neutralization of the acidity in the rain. The relative magnitude of average ionic concentrations followed the relation Cl-> $SO_4^{2-}$) $Na^+$> Ca^{2+}$> NH_4^+$> NO_3^-$> $Mg^{2+}$> $K^+$. The ions associated with sea salt, namely $Na^+$ and $Cl^-$, dominated the total concentration of ions in the rainwater and the $SO_4^{2-}$ ion accounts for 20% of total concentration. [H+][nss-SO42-+NO3] ratio and a multiple regression for $SO_4^{2-}$ and NO3- ions against $H^+$, $Ca^{2+}$ and $NH_4^+$ suggested that all of $SO_4^{2-}$ and $NO_3^-$ in rainwater was not necessarily associated with $H_2SO_4$ and $HNO_3$, but might also occur in combination with $NH_4^+$ or Ca^{2+}$. The monthly mean concentrations of $SO_4^{2-}$-, Ca^{2+}$ and $NH_4^+$ in spring time was higher than those in other seasons. These results may De attributed to the fertilizer application as the local sources and the yellow sand phenomina as a regional-scale sources.

• 분석과학
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• 제15권4호
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• pp.321-328
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• 2002

From May 1999 to July 2000, concentration of 17 metals (Al, Ba, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Pb, Sr, V, Zn), 4 ions (${NH_4}^+$, $Cl^-$, ${NO_3}^-$, ${SO_4}^{2-}$) and pH in rainwater were investigated. The volume-weighted mean concentrations (VWM) of ${NO_3}^-$ and ${SO_4}^{2-}$ were 16.0 and $17.0{\mu}mol\;L^{-1}$. The average pH was 4.53, which ranged from 3.83 to 6.06. The characteristic variations of these species were investigated in terms of the source of these species by principal component analysis (PCA) and interelement correlation coefficients. The elements were classified into three categories: anthropogenic source (Cd, Cu, Fe, Ni, Pb, V, Zn, ${NH_4}^+$, ${NO_3}^-$, ${SO_4}^{2-}$ and $H^+$), soil and crust dust (Al, Ba, Ca, Fe, Mn) and sea salts (Mg, Na, $Cl^-$). In addition, we compared the concentrations in rainwater, which were taken on the same day in three sites (Higashi-Hiroshima, an urban-facing area and a mountain-facing area of Mt. Gokurakuji) in order to examine the regional effect against the concentrations in them. At the urban-facing area of Mt. Gokurakuji, the concentrations of chemical compositions were higher than other areas.

• Asian Journal of Atmospheric Environment
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• 제11권2호
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• pp.71-78
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• 2017

Monthly characteristics of rainwater chemistry at a coastal site in southwestern Japan were examined based on an eight year record. In the period November-May when rain was mainly caused by cyclones, the monthly mean concentrations of $nss-{SO_4}^{2-}$, ${NO_3}^-$, ${NH_4}^+$, $nss-Ca^{2+}$, $Na^+$ and $Cl^-$ over the eight years were 25.1-57.8, 9.9-25.0, 11.3-31.4, 5.5-18.7, 24.2-154.9 and $30.0-178.5{\mu}eq\;L^{-1}$, respectively. In June and July when rain was mainly caused by stationary fronts, i.e. Meiyu fronts, the concentrations were 14.4-20.7, 7.2-9.5, 7.7-12.9, 4.1-6.8, 21.7-33.6 and $26.4-40.5{\mu}eq\;L^{-1}$, respectively. In August and September when typhoons contributed substantial rainfall, the respective concentrations of $Na^+$ and $Cl^-$ were as high as 97.7-105.3 and $116.8-122.9{\mu}eq\;L^{-1}$, while the concentrations of other ions were low. These results indicate a large variation of monthly rainwater chemistry, which is basically dependent on the synoptic weather patterns causing rain. From later autumn to early spring, rain contains ions in high concentration and large variation ranges. In the Meiyu season, rain contains less ions which vary in a range much smaller than that in later autumnearly spring. In summer and autumn, the concentrations are low, except $Na^+$ and $Cl^-$ which can be large due to typhoons' contribution.

• 한국환경농학회지
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• 제18권3호
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• pp.204-208
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• 1999

태안지역 빗물의 화학적 특성을 알아보기 위하여 '98년 영농기(5월${\sim}$10월) 동안 태안지역에 내린 빗물의 화학적 성분조성과 분석결과의 신뢰성을 조사한 결과는 다음과 같다.각 분석시료에 대한 이온균형과 전기전도도 수지를 조사한 결과, 고농도 시료를 제외하고는 분석의 신뢰성이 인정되었다. 빗물의 pH별 분포는 pH $4.5{\sim}5.0$ 및 $5.0{\sim}5.6$ 범위에서 각각 43%와 38%이었으며, 강우량별 빗물의 이온함량과 pH 변화는 초기강우(1mm 이하)가 그 이후의 강우에 비해 높았다. 빗물의 조성은 $SO_4\;^{2-}$와 $NO_3\;^-$가 음이온의 80% 이상 그리고 양이온은 $NH_4\;^+$와 $Ca^{2+}$가 60% 이상을 차지하고 있었다. 월별 빗물의 pH는 강우량이 많았던 8월에 4.3으로 가장 낮았고 조사지역 강우중 비해염 sulfate는 총 sulfate 함량의 약 97%이었다. 빗물의 $nss-SO_4\;^{2-}/NO_3\;^-$비는 평균 2.4로 비해염 $SO_4^{2-}$의 강우 산성도에 대한 기여율이 $NO_3\;^-$보다 2.4배 높았다.

• 한국대기환경학회지
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• 제5권2호
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• pp.1-11
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• 1989

Sandy dust phenomena was observed from April 19 to 23, 1988 in Seoul. During this period it rained and the precipitation was collected to investigate the rain chemistry. This study was carried out to analyzed the chemical composition of precipitation by the measurements of conditivity, cations $(H^+, NH_4^+, K^+, Na^+, Ca^{2+}, MG^{2+})$, and anions $(SO_4^{2-}, NO_3^-, Cl^-, F^-, Br^-)$ which are believed to be the major ions playing an important role in the acidity of rain water. During the period of sandy dust phenomena the range of pH value and conductivity concentration of rainwater were 6.0-6.7, 172-254 $\mu \mho/cm$. The anions and cations concentrations increased and the orders of these concentrations were $SO_4^{2-} > Cl^- > NO_3^- > Na^+ > Ca^{2+} > NH_4^+ > Mg^{2+}$. THe principal chemical compounds of rainwater were estimated at $(NH_4)_2 SO_4, CaSO_4, NaCl, and MgCl_2$.

• 한국대기환경학회지
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• 제15권2호
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• pp.101-111
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• 1999

In previous study, the local trends in dustfall chemistry and deposition were determined and the characteristics of chemical compositions among dustfall, TSP and rainwater were also compared. Based on the previous results, in this study, the effects of sea salts and soil and soil on the chemical composition of dustfall were studied and then the sources of dustfall in Cheju area were tentatively identified by principal component analysis(PCA)