• 한국환경과학회지
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• 제5권2호
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• pp.171-178
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• 1996

This experiment was performed with the purpose of finding out the effect of simulated acid rain at various pH levels on the morphology and enzyme of Perilla frutescens var. japonica hara. The pH levels of simulated acid rain ranged from pH 2.0 to pH 6.0. The experiment showed the anion concentrations in the order of $SO_4^{2-}$, Cl^-$, $NO_3^-$, and $F^-$, $SO_4^{-2}$ was found out to be the main factor which contributed to the rainwater acidification. A general decrease of growth in Perilla frutescens var. japonica hara growth was shown with the decreas of pH concentration. As acidity increases a definite reduction in the rates of germination, heigth of plant, malate dehydrogenase, and 6-phosphogluconate dehydrogenase was ovserved, but the density of spots on the leaf apex was increased.

• Journal of Ecology and Environment
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• 제34권4호
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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.

• 한국산림과학회지
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• 제76권1호
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• pp.33-40
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• 1987

잣나무(Pinus koraiensis) 파종상(播種床)에 인공산성우(人工酸性雨)로 처리(處理)하고 생장(生長), 엽내함유성분(葉內含有成分) 그리고 배지(培地) 토양(土壤)의 화학적(化學的) 성질(性質)에 미치는 영향(影響)을 산도수준(酸度水準)에 따라 평가(評價)하였다. 잣나무 종자(種子)를 1985년(年) 봄에 묘포토양(苗圃土壤)을 채운 pot에 파종(播種)하고, 해당지역(該當地域)의 30년간(年間)의 강우양식(降雨樣式)에 모의(模擬)(simulation)해서, 황산(黃酸)과 질산(窒酸)의 비율(比率)을 3:2로 혼합(混合)하여 지하수(地下水)로 희석(稀釋)한 pH 4.0 및 pH 2.0의 산성우(酸性雨)와 지하수(地下水)(pH 6.5)를 5월(月)부터 8월(月)까지 4개월간(個月間)에 걸쳐 살포(撒布)하고, 동년(同年) 10월(月) 30일(日) 시료(試料)를 채취(採取)하여 분석(分析)한 결과(結果)는 다음과 같았다; 1) 잣나무 파종묘(播種苗)의 엽내함유성분(葉內含有成分)의 함량(含量)은 산성우(酸性雨)의 pH 값이 저하(低下)됨에 따라 S와 $K_2O$는 증가(增加)를, MgO 와 $P_2O_5$는 감소(減少)되었다. 2) 산성우(酸性雨)의 pH 값이 낮아짐에 따라 토양산도(土壤酸度)는 저하(低下)되었고, 치환성(置換性) Al 함량(含量)은 크게 증가(增加)하는 상반(相反)된 반응(反應)을 보였다. 3) 토양(土壤)의 치환성(置換性) Ca, Mg 및 K의 함량(含量)과 염기총량(鹽基總量), 염기포화도(鹽基飽和度)는 산성우(酸性雨)의 pH 값이 낮아짐에 따라 현저(顯著)하게 감소(減少)되었다. 4) 토양내(土壤內) sulfate 함량(含量)은 산성우(酸性雨)의 pH 값이 저하(低下) 될수록 크게 증가(增加)하였다.

• 생명과학회지
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• 제10권6호
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• pp.598-604
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• 2000

This study was conducted to investigate the effect of simulated acid rain (SAR) on germination, growth, acid buffering capacity and nutrient leaching in Impatiens balsamina L. and Tagetes patula L.. In both species, germination was not inhibited at pH 4.0, but the germination rate decreased at the lower pH of 3.0, showing higher rate in Inpatiens balsamina L. than Tagetes patula L.. As the pH decreases, the growth of radicle was markedly decreased than that of hypocotyl in both species. The plant height, root length, leaf area, total dry weight, relative growth rate and net assimilation rate were inhibited by SAR. The acid buffering capacity in the leaves were increased at pH 4.0, on the other hand, it was shown a tendency to decrease at pH 2.0 in both species. As the pH levels decreased from 5.6 to 2.0, the nutrient leaching from leaves was significantly increased in both species. Based on the results, there are a great difference in the responses to SAR between the two species. In general, Tagetes patula L. represented a higher tolerance to SAR than Impatiens balsamina L.. These results suggested that interspecific variation in the acid buffering capacity and nutrient leaching from leaves may be responsible for the interspecific susceptibility to SAR.

• 한국산림과학회지
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• 제77권3호
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• pp.259-268
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• 1988

인공산성우(人工酸性雨)가 소나무(Pinus densiflora) 유묘(幼苗)와 개나리(Forsythia koreana) 삽목묘(揷木苗)의 식물체내(植物體內) 함유성분(含有成分)에 미치는 영향(影響)을 조사(調査)하였다. 소나무 식재(植栽)와 개나리 삽목(揷木)은 1986년(年) 3월(月) 25일(日) 묘포토양(苗圃土壤)과 사양질(砂壤質)의 산림토양(山林土壤)을 1:l(v/v)로 혼합(混合)하여 채운 pot에 실시(實施)되고, 해당지역(該當地域)의 30년간(年間)의 강우양식(强雨樣式)에 모의(模擬)(simulation)해서, 황산(黃酸)과 질산(窒酸)의 비율(比率)을 3 : 2(규정(規正) 농도(濃度))로 혼합(混合)하여 지하수(地下水)로 희석(稀釋)한 pH 2.0, pH 4.0 및 pH 5.5(대조용(對照用))의 산성우(酸性雨)를 난괴법(亂塊法) 3반복(反復) 시험구(試驗區)에 천연강우(天然降雨)를 차단(遮斷)한 가운데, 동년(同年) 5월(月) 1일(日)부터 8월(月) 31일(日)까지 4개월(個月)에 걸쳐 산포(散布)하고, 묘목(苗木)의 생장(生長)이 멈춘 시기(時期)에 시료(試料)를 채취(採取)하여 분석(分析)한 결과(結果)는 다음과 같았다 ; 1) 식물체내(植物體內) 전질소(全窒素) 함량(含量)은 산성우(酸性雨) 처리(處理)에 두 수종(樹種) 모두 증가(增加) 경향(傾向)이 있었으며, 소나무는 뿌리와 1년생(年生) 줄기에서, 개나리는 잎과 뿌리에서 각각 차이(差異)가 있었다. 2) 식물체내(植物體內) 인산(燐酸)의 함량(含量)은 산성우(酸性雨) 처리(處理)에 두 수종(樹種) 모두 감소(減少) 경향(傾向)이 있었으며, 소나무는 뿌리에서, 개나리는 잎과 뿌리에서 큰 차이(差異)를 보였다. 3) $K_2O$, CaO 및 MgO의 함량(含量)은 산성우(酸性雨)의 pH 값이 낮아짐에 따라 두 수종(樹種) 모두 감소(減少)하였으며, 개나리가 소나무에 비해, 그리고 잎과 뿌리가 줄기 및 가지에 비해 민감(敏感)한 반응(反應)을 보였다. 4) 유황(硫黃)의 함량(含量)은 pH 2.0 처리(處理)에서 두 수종(樹種) 모두 크게 증가(增加)하였으며, 소나무는 잎과 뿌리에서, 개나리는 잎, 줄기, 뿌리의 전부위(全部位)에서 각각 처리간(處理間)에 고도(高度)의 유의차(有意差)를 보였다. 5) 인공산성우(人工酸性雨)의 산도수준(酸度水準) 및 수종(樹種)에 대한 반응(反應)을 종합(綜合)하면, 산도수준별(酸度水準別)로는 산성우(酸性雨)의 pH값이 낮야짐에 따라, 그리고 수종별(樹種別)로는 개나리가 소나무에 비해 민감(敏感)한 반응(反應)을 보였다.

• Journal of Plant Biology
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• 제38권1호
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• pp.79-86
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• 1995

은행나무와 곰솔의 잎은 pH 3.2 이하의 인공산성비 처리구에서 괴사반점과 황화현상 및 조기노화 현상이 나타났다. 잎표면 구조의 관찰에서 은행나무 잎은 pH 2.4의 처리구에서 잎표면 왁스층의 침식이 심하게 일어난 반면 곰솔의 경우 pH 4.0 이하의 처리구에서 왁스층의 침식이 심하게 일어났다. 은행나무 잎은 pH 3.2 이하에서 표피세포와 해면조직에서 구조의 변화가 나타났으나 유관속조직은 정상적인 구조를 나타냈다. 엽육세포의 크기는 산도가 높아질수록 작아지고 세포간극이 커졌다. 곰솔의 잎은 표피세포보다 엽육조직과 유관속조직의 피해가 현저하였다. 은행나무의 기공의 크기와 모양은 인공산성비의 영향을 받지 않았으나 기공지수와 기공의 공극 크기는 높은 산도에서 증가하였다. 또한 인공산성비가 처리된 은행나무와 곰솔 잎의 기공들은 열려 있었다.

• The Korean Journal of Ecology
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• 제17권2호
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• pp.131-141
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• 1994

One-year-old yellow-poplar (Liriodendron tulipifera L.) and sweetgum (Liquidambar styraciflua L.) seedlings were exposed to 0.10 ${\mu}l/l\;O_3$and simulated acid rain at pH 3.0 for ten consecutive weeks. Shoot height growth (SHG), fresh weight (FWT), dry weight (DWT), apparent plastochron duration (APD) and foliar nutrient concentrations were measured. None of growth measurements, except the apparent plastochron duration (APD), were significantly affected by any treatment in yellow-poplar seedlings. APD was approximately 30% higher in seedlings exposed to $0.1{\mu}l/l\;O_3$ ＋ pH 5.6 solution than any other treatment. Ozone significantly reduced SHG of sweetgum seedlings by 24% at the end of the ten-week fumigation. There were also significant effects of single and combined effects of ozone and simulated acid rain on APD in sweetgum. APD was significantly increased by 19.8% and 25.7% in seedlings exposed to $0.1{\mu}l/l\;O_3$ and pH 5.6 solution, respectively, and resulted in 46.1% higher APD in seedlings exposed to $0.1{\mu}l/l\;O_3$ + pH 5.6 solution compared with seedlings exposed to $0.0{\mu}l/l\;O_3$ ＋ pH 3.0 solution. Phosphorus and sulphur were significantly greater in seedlings exposed to simulated rain at pH 3.0 compared with pH 5.6 for both species. Foliar S concentration was higher in seedlings exposed to $0.0{\mu}l/l\;O_3$ ＋ pH 3.0 than in seedlings exposed to any other treatment in sweetgum. Ozone significantly increased Ca in sweetgum seedlings, however, ozone reduced Ca in yellow-poplar. Ozone also reduced S and Mg in sweetgum seedlings.

• 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.

• Interaction and multiscale mechanics
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• 제5권1호
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• pp.41-56
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• 2012

This study is focused on evaluation of the tensile properties of concrete exposed to acid rain environment. Acid rain environment was simulated by the mixture of sulfate and nitric acid in the laboratory. The dumbell-shaped concrete specimens were submerged in pure water and acid solution for accelerated conditioning. Weighing, tensile test, CT, SEM/EDS test and microanalysis were performed on the specimens. Tensile characteristics of the damaged concrete are obtained quantitatively. Evolution characteristics of the voids, micro cracks, chemical compounds, elemental distribution and contents in the concrete are examined. The deterioration mechanisms of concrete exposed to acid rain are well elucidated.

• Structural Engineering and Mechanics
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• 제52권1호
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• pp.35-49
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• 2014

This paper studies the behaviour of deteriorated reinforced concrete (RC) beams attacked by various forms of simulated acid rain. An artificial rainfall simulator was firstly designed and evaluated. Eleven RC beams ($120mm{\times}200mm{\times}1800mm$) were then constructed in the laboratory. Among them, one was acting as a reference beam and the others were subjected to three accelerated corrosion methods, including immersion, wetting-drying, and artificial rainfall methods, to simulate the attack of real acid rain. Acid solutions with pH levels of 1.5 and 2.5 were considered. Next, ultrasonic, scanning electron microscopy (SEM), dynamic, and three-point bending tests were performed to investigate the mechanical properties of concrete and flexural behaviour of the RC beams. It can be concluded that the designed artificial simulator can be effectively used to simulate the real acid rainfall. Both the immersion and wetting-drying methods magnify the effects of the real acid rainfall on the RC beams.