• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.209-212
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• 2005

Concrete structures such as buildings and bridges etc in urban areas may be damaged due to exposure to cloud water with high acidity for a long time. Acid precipitation with a pH level raining between 3.0 and 5.0 will affect concrete. A pH level of rain acid in Korea is between 4.3 and 5.3. However, few studies have been systematically investigated for the effect of rain acid on concrete structures. Therefore, this study is investigated the domestic situation of acid rain and the effect of acid rain on concrete deterioration by existing literatures as a study to analyze the effect of rain acid on concrete structures.

• 한국환경생태학회지
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• 제7권1호
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• pp.10-21
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• 1993

소나무, 곰솔, 젓나무 및 독일가문비를 대상으로 인위적으로 산도를 조절한 인공산성우(PH 3.0, 4.0 및 5.0)와 지하수(pH 6.5)를 1991년 4월부터 1993년 8월까지, 생육기간 중에는 주 2~3회, 겨울철은 주 1회 1회 5mm의 강도로 처리하였다. 인공산성우를 처리하면서 수종별 발아 및 득묘율, 토양산도, 유묘의 생장 및 접촉각(contact angle)을 조사.비교하여 얻은 결과는 다음과 같다. 묘목의 생장관련 형질(묘고, 지하부, 엽량 및 개체당 건중량)의 경우에는 산성우처리 초기에는 산성우 처리가 양료로서의 효과를 가지는 것으로 판단되며, 수종별로 상이한 반응을 보였다. 그러나 처리가 2년 이상 지속된 3차년도에서는 처리산성우의 산도수준이 높을수록 모든 수종에서 생장관련 형질들이 감소되는 경향을 보였으며, 이는 토양완충력의 한계 이상으로 투하되는 산집적에 의한 결과로 판단된다. 엽피해율이나 엽량(낙엽율)등의 자료는 처리산성우의 산도수준과 관련지어져 있는 것으로 나타나 산성우 피해의 조기판단 기준으로 사용가치가 높을 것으로 판단된다. 토양산도는 처리간 고도의 통계적 유의차가 인정되었다. 침엽의 표면과 물방울이 이루는 접촉각을 측정한 결과, 처리산성우의 산도수준이 높을수록 엽령이 높을수록 접촉각의 크기는 낮아졌다. 접촉각을 측정비교하는 방법은 야외에서 침엽수류에 대한 산성우 피해의 조기판단을 위한 알맞고 훌륭한 기준이라 판단된다.

• 한국환경과학회지
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• 제12권4호
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• pp.367-373
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• 2003

The focus of this study was to identify and describe environmental preconceptions held by pre-service elementary teachers about three issues : greenhouse effect, ozone layer depletion and acid rain. Two hundred and twenty nine pre-service elementary teachers participated in this study. A 36 question survey was created by one of the authors. The questions focused on the cause, effects, and interactions of three environmental issues greenhouse effect of one layer depletion and acid rain. Pre-service elementary teachers answered the questions on a Likert scale. An analysis of the survey data indicated that the majority of pre-service elementary teachers possess an array of incorrect conceptions about the causes and effects of the greenhouse effect ozone layer depletion, and acid rain. and also many pre-service elementary teachers thought that there were causal relationships among the increase in greenhouse effect, the destruction of ozone layer, and the increase of acid rain.

• 생명과학회지
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• 제8권3호
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• pp.299-304
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• 1998

In order to clarify the effects of acid rain on soil microorganisms, the inpact of acid to soil microorganisms was survyed for 14 weeks using soil microcosms from industrial site A and B, Gaejok mountain, and Daechong lake in Taejeon area. The acid tolerant-microorganisms in natural soil, using culturing method were counted to be 5.8 - $8.0{\times}10^6$CFU/g soil. The number of microorganisms using ATP-biomass analysis for natural soil samples were also analyzed and 2.2 - $2.6{\times}10^9$ cell/g soil in industrial site A and B, Gaejok mountain, and Daechong lake were determined. In soil samples, which were treated with artificial acid rain, the number of acid tolerant microorganisms were counted 2.9 - $5.8{\times}10^5$ and 2.8 - $7.5{\times}10^8$, respectively. Therefore, we conformed that the numver of soil microorganisms were influenced by acid rain. Also, long term acid tolerant microorganisms were identified as Rhodotorula sp. and Pseudomonas sp.

• 한국대기환경학회지
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• 제4권1호
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• pp.33-44
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• 1988

For the purpose of examining the effects of simulated acid rain on the chemical properties of the experimental soil in Pinus 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 : V/V)in the early spring of 1985. The regime of artificil acid rain, in terms of spray frequency per monthly 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, pH4.0, and pH 5.5 as control) containing sulfuric and nitric acid in the ratio of 3:2 (chemical equivalant basis) diluted 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 1985. THe results obtained in this study were as follows; 1. Soil acidity was dropped, and exchangeable aluminum contents in the soil was dramatically increased in both species, with decreasing pH levels of acid rain. 2. Exchangeable potassium, clacium, magnesium contents, and base saturation degree of the soil were highly drcreased in two species as the pH levels of acid rain decreased. 3. In two species, sulfate concentrations in the soil were decreased of pH 4.0 treatment, and remarkably increased at pH 2.0 treatment of acid rain in comparison with control. 4. Total nitrogen and available phosphate contents of the soil were not affected by acid rain treatment in the both species, and Fe contents at pH 2.0 treatment were highest among three acid rain treatments.

• The Korean Journal of Ecology
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• 제21권1호
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• pp.65-72
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• 1998

Various effects of simulated acid rain by $HNO_3$ and $H_2SO_4$ with pH 3.2, 4.2 and 5.6 were investigated in Melilotus suaveolens Ledeb, a biennial legume dominating the disturbed and poor soil vegetations. The nitric acid treatment of pH 3.2 resulted in 121% increase of the plant height compared to that of pH 5.6 during early growth, although 17% decrease was detected with the sulfuric acids. During 14 days of treatment, leaf biomass and chlorophyll content increased 168% and 133% with pH 3.2 nitric acid rain but decreased 20% and 38%, respectively, with sulfuric acid rain. Nitrogen content in various organs was also determined after 42 days of nitric acid treatment. It increased 480% and 387% by pH 3.2 and 4.2 in leaves, 212% and 214% in stems and 247% and 249% in roots. However, the same treatment with the sulfuric acid showed a considerable reduction in this content, indicating that the nitric acid was a nitrogen source. Nodule formation assayed revealed 15% decrease with pH 3.2 in contrast to 157% increase in pH 4.2, further suggesting an enhancement effect by the additional nitrogen source. Contrary to this, the nodule formation was reduced up to 43-71% by sulfuric acid rains. Specific nitrogen fixation activities of nodules estimated at pH 3.2, 4.2 and 5.6 nitric acid rain were 36.7, 42.8 and 47.3 ${\mu}mol\;C_2H_4{\cdot}g^{-1}\;fw\;nodule{\cdot}h^{-1}$, while those of sulfuric acid rain exhibited 1 nmol $C_2H_4{\cdot}plant^{-1}{\cdot}h^{-1}$ with pH 3.2, 177 with pH 4.2 and 179 with pH 5.6, yet it increased 2, 115 and 286 respectively corresponding to the three sulfuric acid concentrations. Further implications of the simulated acied rain were also discussed in the study.

• 한국환경농학회지
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• 제13권3호
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• pp.346-358
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• 1994

In this paper, the current knowledge on the formation of acid rain and its effect on vegetation are reviewed. The pollutants which were emitted into the air are oxidized by photochemical reaction and affect the vegetation by dry and wet deposition. Acid rain at pH 4.0 affected sensitive plants and when it was below pH 3.0, visible symptoms developed in most of the crops. The acid rain treatment at pH 2.0 decreased dry weight, leaf area and chlorophyll contents in soybean but it increased rate of photosynthesis and respiration rate. Rain treatment at pH 2.8 increased ethylene production, but it’s not a suitable indicator of sensitivity to acid rain. At pH 2.0 treatment, the contents of soluble Mn and Al were increased but the cultivated soil pH at upper layer(0-5cm) was significantly decreased. The pertubation of glandular trichome which is existed along the vein was developed at all treatment except the control(pH 6.0) and non-treatment. Histological pertubation of spiked trichome and disintegration of chloroplast were developed only on the leaves of sesame treated with SAR(simulated acid rain) of pH 2.0.

• 한국산림과학회지
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• 제83권1호
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• pp.32-37
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• 1994

리기다소나무와 잣나무 유묘에 인위적으로 산도를 조절한 인공산성우(pH 3.0, 4.0 및 5.0)와 지하수(pH 6.5)를 1992년 4월부터 1993년 8월까지, 생육기간 중에는 주 2회, 겨울철은 주 1회 1회 5mm의 강도로 처리하였다. 인공산성우를 처리하면서 수종별 침엽의 접촉각(contact angle)을 조사 비교하여 얻은 결과는 다음과 같다. 침엽의 표면과 물방울이 이루는 접촉각을 측정한 결과, 처리산성우의 산도수준이 높을수록 엽령이 높을수록 접촉각의 크기는 낮아졌다. 침엽의 접촉각을 측정 비교하는 방법은 야외에서 침엽수류에 대한 산성우 피해의 조기판단을 위한 매우 효과적인 기준이라 판단된다.

• Geomechanics and Engineering
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• 제34권5호
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• pp.473-480
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• 2023

Acid rain of soils has a significant impact on mechanical properties. An X-ray diffraction test, scanning electron microscope (SEM) test, laser particle size analysis test, and triaxial unconsolidated undrained (UU) test were carried out in red clay soils with different compaction degrees under the effect of different concentrations of acid. The experiments demonstrated that: the dissolution effect of acid rain on colluvium weakened with the increase in the compacting degree under the condition of certain pH values, i.e., the damage to the structure of red clay soil was relatively light, where the number of newly increased pores in the soil decreased and the agglomeration of soil particles increased; for the same compacting degree, the structural gap decreased, and the agglomeration increased with the increase in the pH value (acidity decreases) of the acid rain; the dissolution rate of Si, Al, Fe, and other elemental minerals and cement in red clay soil was found to be higher under the effect of acid rain, in turn destroying the original structure of the soil body and producing a large number of pores. This is macroscopically expressed as the decrease of the soil cohesion and internal friction angle, thereby reducing the shear strength of the soil body.

• 한국대기환경학회지
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• 제19권2호
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• pp.191-204
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• 2003

A one dimensional time dependent acid rain model considering size distribution of aerosols and hydrometeors is developed to predict observed chemical and physical properties of precipitation. Temporal variations of anions and cations observed are predicted fairly well with acid rain model simulations. It is found that aerosol depletion rates are highly dependent on aerosol sizes under the assumption of Marshall - Palmer raindrop size distribution. Also, the aerosol depletion during the initial rain event largely influences on ion concentrations in rainwaters.