• Journal of Korean Society for Atmospheric Environment
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• v.9 no.2
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• pp.147-153
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• 1993

From March 1990 to August 1991, every each 5mm bulk precipitation samples were collected at one residental area in Taejon City to investigate chemical characteristics of acid rain. Major ion concentrations of rain samples $(pH, SO_4^{2-}, NO_3^-, CL^-, NH_4^+, Na^+, K^+, Ca^{2+}, Mg^{2+})$ were analysed and compared with the concentration of air pollutants (T. S. P, $SO_2, NO_x$) that were measured by Ministry of Environment. The results of statistical analysis are as followings. Rain pH was relatively high on October and January and relatively low on August, November and February. Major anion is sulfate, and it's concentration is 2.36 times higher than nitrate's, and major cations are ammonium, sodium and calcium ion. Monthly variation of sulfate and calcium concentrations are higher than the others. Ion concentration and rain pH were correlated negatively with rainfall amount. Major ions in rain samples were $SO_4^{2-}, NO_3^-, NH_4^+, Ca^{2+}$ and regression equations are proposed by multiple regression of measured data. Also, regression equation between air pollutants(T. S. P, $SO_2$) and $SO_4^{2-}, Na^+, K^+, Ca^{2+}, Mg^{2+} ions in rain samples were made. From this wer can predict rain pH.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.401-410
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• 2011

We assayed the effects of simulated acid rain on the mass loss, $CO_2$ evolution, dehydrogenase activity, and microbial biomass-C of decomposing Sorbus alnifolia leaf litter at the microcosm. The dilute sulfuric acid solution composed the simulated acid rain, and the microcosm decomposition experiment was performed at 23$^{\circ}C$ and 40% humidity. During the early decomposition stage, decomposition rate of S. alnifolia leaf litter, and microbial biomass, $CO_2$ evolution and dehydrogenase activity were inhibited at a lower pH; however, during the late decomposition stage, these characteristics were not affected by pH level. The fungal component of the microbial community was conspicuous at lower pH levels and at the late decomposition stage. Conversely, the bacterial community was most evident during the initial decomposition phase and was especially dominant at higher pH levels. These changes in microbial community structure resulting from changes in microcosm acidity suggest that pH is an important aspect in the maintenance of the decomposition process. Litter decomposition exhibited a positive, linear relationship with both microbial respiration and microbial biomass. Fungal biomass exhibited a significant, positive relationship with $CO_2$ evolution from the decaying litter. Acid rain had a significant effect on microbial biomass and microbial community structure according to acid tolerance of each microbial species. Fungal biomass and decomposition activities were not only more important at a low pH than at a high pH but also fungal activity, such as $CO_2$ evolution, was closely related with litter decomposition rate.

• Journal of Korean Society of Forest Science
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• v.84 no.1
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• pp.97-102
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• 1995

The purpose of this study was to investigate the effect of artificial acid rain(pH2.0, 3.0. 4.0 and 5.0) adjusted by natural rain fall and control group by pH6.5 on the change in needle chlorophyll fluorescence of Pinus densiflora and Pinus thunbergii. This study was performed from May, 1994 to August, 1994, during which 20ml of artificial acid rain was used once a week. The results are as follows : In the first treatment of artificial acid rain the measured indexes of fluorescence have increased in pH4.0 and pH5.0 treatments and decreased in pH2.0 and pH3.0 in comparison with those of the control group. As the treatment of artificial acid rain was processed the fluorescence indexes of both Pinus densiflora and Pinus thunbergii have decreased as the degree of acidity increased higher and that of Pinus densiflora has decreased more significantly than Pinus thunbergii. The measurement of change in the numerical indexes of fluorescence was proved to be a very effective criterion to make an early decision of damage of the vegetation by acid rain.

• Journal of Korean Society of Forest Science
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• v.77 no.3
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• pp.259-268
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• 1988

For the purpose of examining the effects of simulated acid rain on nutrient contents of plant tissues in Pintos densiflora seedlings and Forsythia koreana rooted cuttings, the experimental design of randomized block arrangement with three replications was implemented in the experimental field of Yesan National Agricultural Junior College. One-year-old Pinus densiflora seedlings and Forsythia koreana cuttings were planted in the pots filled the mixed soils(nursery soil : forest soil of siliceous sandy loam=1 : 1 v/v) in the early spring of 1986. The regime of artificial acid rain, in terms of spray frequency per month and spray amount at single treatment per plot, was simulated on the basis of climatological data averaged from 30 years records. Simulated acid rain(pH 2.0, pH 4.0, and pH 5.5 as control) containing sulfuric and nutric acid in the ratio of 3 : 2(chemical equivalant basis) diluted with ground water were treated on the experimental plants under condition of cutting off the natural precipitation with vinyl tunnel, during the growing season(May 1 to August 31) in 1986. The results obtained in this study were as follow : (1) As for the nitrogen contents in plant tissues, P. densiflora increased significantly in one-year-old stembranch and root tissues, and F. koreana increased significantly in leaf and root tissues, as the pH levels of acid rain decreased. (2) The available phosphate contents in root tissues of P. densiflora, and in leaf and root tissues of F. koreana were significantly decreased, as the pH levels of acid rain decreased. (3) $K_2O$, CaO and MgO contents in plant tissues were significantly decreased in the both species as the pH levels decreased. And the effects of acid rain on F. koreana were higher than those of P. densiflora. (4) Sulfur contents of plant tissues in the both species were increased at pH 2.0 treatment. There were significant differences among three acid rain treatments in leaf and root tissues of P. densiflora, and in all parts of F. koreana. (5) In the effects of simulated acid rain on the both species and the tested soils, in general, F. koreana revealed higher sensitiveness than P. densiflora, and the lower pH levels of simulated acid rain were treated, the more sharp reaction was showed.

• Journal of the Mineralogical Society of Korea
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• v.26 no.4
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• pp.273-283
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• 2013

The artificial rain (pH 4.0, pH 5.6 and pH 6.85) and weathering simulation test are applied in dolomitic marble for the prediction of deterioration of the stone monuments constructed with carbonate rock by acid rain. pH of the applied rain all increase to about neutral pH after reaction of marble. The contents of $Ca^{2+}$ and $Mg^{2+}$ have increased more than twofold in two acid rain and deionized neutral rain after reaction of marble. The weight of marble is expected to decrease $0.00037kg/m^2$ each test cycle by pH 4.0 rain. This weight reduction rate of marble is 1.4 and 3.1 times more in pH 5.6 and pH 6.85 rain respectively, and 3.7 times more in only artificial weathering test. The compressive strength of marble is expected to decrease 0.2468, 0.1791 and $0.1280kg/m^2$ per test cycle with pH 4.0, pH 5.6 and pH 6.85 rain, respectively. These results mean that more acidic rain more enfeeble the strength of marble. Dolomite and small amount of calcite are precipitated in the rains after reaction of marble.

• Journal of the Mineralogical Society of Korea
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• v.22 no.1
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• pp.35-47
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• 2009

The deteriorations of stone monuments located in Gyeongju area are predicted in a modeling study. Artificial rain and accelerated weathering test are here applied to the Gyeongju Namsan granite and cement mortar. They are reacted with pH 4.0, pH 8.0 and pH 5.6 rain, respectively. The two former values are the limited acidity values in the Gyeongju (the acidity of rain of the Gyeongju were pH $4.93{\sim}6.39$ in 2005) and the latter is the limited acidity of acid rain. The rains of pH 5.6 and pH 8.0 reach close to a value of pH 7.0 after the reaction with the Gyeongju Namsan granite. After application of the artificial rain and weathering test, the weight of specimens were reduced and the contents of soluble ions in the specimens were increased. These results are attributable to solution of minerals in the specimens. At first, the microlithic have dissolved in ground from the reaction with acid rain. And then mainly quartz, plagioclase and orthoclase bound by the microlithic are disintegrated. The cement mortars are dissolved after the reaction with not only acid but alkali rain. The concentrations of ions in the dissolved cement mortar are higher than those in granite.

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.05a
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• pp.31-31
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• 2002

• Journal of the Korean Chemical Society
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• v.44 no.1
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• pp.10-16
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• 2000

In general, acid rain is unbuffered solution with low ionic strength and high resistance. Therefore during the pH measurement of acid rain, error can be occurred due to the liquid junction potential difference between the sample and the standard solution. Actually the average conductivity of rain in Taeduk Science Town during 1998 is 12.8 ${\mu}S/cm$, while that of pH standmd solutions is about 5,980 ${\mu}S/cm$. There is a large difference in ionic strength. To compensate the bias due to residual liquid junction potentials, a quality control standard(QCS) of dilute sulfuric acid, which has the conductivity and pH values simikw to rain, was prepared. The pH of QCS solution was determined using the hydrogen electrode system without liquid junction, and compensation has been made for the bias terms by performing the pH measurements with glass electrode. On the basis of this compensation method, the pH vaiues of rain in Taeduk Science Town during 1998 were measured.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.169-180
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• 2005

Nitrogen dioxide concentration was being grown ca. 8% per year although sulphur dioxide concentration was being reduced ca. 10% per year in Seoul from 1996 to 2003. The rainwater was heavily acidic with pH 4.19 to 4.68 in Seoul during 1980 to 1991. Acidity score on the basis of the total anion concentration of rainwater follows the higher in sequence with Seoul(Kwanaksan)(341.5 ${\mu}equiv{\cdot}L^{-1}$), Gwangneung(199.2 ${\mu}equiv{\cdot}L^{-1}$) and whole Korea mean(10.3 ${\mu}equiv{\cdot}L^{-1}$). Rainwaters from 38 sampling sites of 16 countries in the world, on the basis of the acidity score, are classified and designated as five acid rain grades(ARG): the least score is founded in Tana Rata(16.2 ${\mu}equiv{\cdot}L^{-1}$), Malaysia where has the best rain but the greatest founded in Chongquing(541.1 ${\mu}equiv{\cdot}L^{-1}$), China where has the worst rain in the world. Even though acidic deposition decrease with time in the world generally, it is expected to increase in Asia, Africa and Mid-South America.

• Journal of the Korean association of regional geographers
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• v.19 no.4
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• pp.764-774
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• 2013

In this study we reviewed how acid rain as the global environmental problems was dealt with geography textbooks from Korea and England. The results are as follows. First, unlike geography textbooks from England, the concept and criteria of acid rain are not explained exactly in Korea geography textbooks. Second, whereas the cause of acid rain was explained with natural and artificial factors in geography textbooks from England, in Korea the artificial factors only were explained. But if the artificial factors only will be introduced to students, they may misunderstand about the acid rain. Third, the results and policies of acid rain were provided in geography textbooks from Korea and England. But whereas they were deal with separately in Korea, in textbooks from England they were provided with their patterns and concrete cases. So it is necessary to provide the exact concept, results and processes of the global environmental problems structurally in geography textbooks. And it is necessary to provide the results and their policies of the global environmental problems with concrete cases for students' understanding and sympathy about them. If the concepts and causes of global environmental problems are not understood previously, it is possible to stimulate only the moral and ethical aspects too much when the results and policies of them is introduced in geography textbooks.