• Journal of Korean Society of Forest Science
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• v.76 no.1
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• pp.33-40
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• 1987

Simulated acid rain (pH 4.0, pH 2.0) containing sulfuric and nitric acid in the ratio of 60:40 (chemical equivalent basis) diluted with underground water, and underground water (pH 6.5) as control were treated on potted Pines koraiensis seeds during the growing season (May 1 to August 31) in 1985. The regime of artificial acid rain, in terms of spray frequency and amount per plot, was simulated on the basis of climatological data averaged for 30 years of records. The seedling growth, contents of chemical substances in needles and chemical properties of the tested soil were compared among the various pH levels of acid rain on October 31, 1985. Following results were obtained. 1. With decreasing pH levels of acid rain, S and $K_2O$ contents in leaf tissue were increased, but MgO and $P_2O_5$ contents were decreased. 2. Soil pH was dropped, and exchangeable aluminum content in the tested soil was dramatically increased as the pH levels of acid rain decreased. 3. Exchangeable calcium, magnesium, potassium contents, and base saturation degree of the soil were significantly decreased with decreasing pH levels of acid rain. 4. Sulfate concentrations in the soil were significantly increased as rain pH decreased, but total nitrogen and available phosphate contents were not influenced by acid rain.

• Korean Journal of Environment and Ecology
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• v.6 no.1
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• pp.1-8
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• 1992

Artificial acid rain (pH 3.0, 4.0 and 5.0) was treated on the seeded pots of 4 species to examine its effects on germination, leaf injury and seedling growth. Artificial acid rain was prepared by diluting sulfuric acid with ground water and ground water (pH 6.5) was used as control. Artificial acid rain was sprayed to seeded pots three times per week. About 5mm of artificial acid rain was treated each time from early April to early October, 1991. Germination, seedling establishment, leaf injury, soil acidity and seedling growth were measured and compared among the treatments. The results were summarized as follows; 1. Germination and seedling establishment rate of Pinus thunbergiana was highest on the pH 4.0 pot whereas that of Picea abies was highest on the pH 3.0 pot. Those of Pinus densiflora and Abies holophylla were not significantly differed among the treatments. 2. The differences in seedling height of all species were not significantly differed among the treatments. 3. Seedling dry weight of Pinus densiflora differed significantly among the treatments. but that of Pinus thunbergiana did not differ. 4. With decrease of pH value of artificial acid rain. the number of injured needle and injured individual tended to be increased. 5. The differences of soil acidity were significant among the treatments for all species.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.3
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• pp.263-268
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• 1996

This study was conducted for the assessment of the effects of acid rain and soil fertilizers on photosynthetic rate, was content, and contact angle on 5-year seedlings of Japanese red pine (Pinus densiflora Sieb. et Zucc.) leaves. The seedlings were exposed to pH 3.0 (simulated acid rain), pH 6.5 (groung water) and rain (pH around 4.6). The seedlings were also treated with $Ca(OH)_2, Mg(OH)_2, and Ca(OH)_2 + Mg(OH)_2 + C.F.(compound fertilizer)$. Photosynthetic rate, stomatal conductance, was content, contact angle value, and mineral nutrient content of the leaves were measured and the results were as follows: 1. Photosynthetic rate and stomatal conductance of the leaves increased with the increase of pH. Photosynthetic rate and stomatal conductance increased with application of soil fertilizer in the pH 3.0 treatment, but showed no changes in the rain and the pH 6.5. 2. Contact angle value and was content of the leaves did not change with the pH treatment, but increased with the fertilizer treatments. 3. Mineral nutrient contents of the leaves were lowest in the rain treatment and highest in the pH 6.5 treatment. The increase of mineral nutrient contents was observed with the soil fertilizer treatments.

• Interaction and multiscale mechanics
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• v.5 no.1
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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.

• Journal of Environmental Science International
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• v.7 no.2
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• pp.123-132
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• 1998

The experiment was performed to elucidate the effect of simulated acrid rain on growth of the seven crops(caucus carota vu sativa DC. , Fagopyrum esculenkm Moench, Brassica cmpespis subsp. napus var. pekinensis Makino , Raphuus satlws vu. hortensis for. acnMormis Makino, Brassica dbogjabra Bailey, Caphslcum mum L., and Perilla frutescens Britton). The pH levels of simulated acid rain ranged pH 3.1, 3.6, 4.1, 4.6, 5.1 and 5.6. The germination 10 each crop was influenced from stimulated acrid rain except buckwheat and kale. A general decrease of growth in crops was observed with Increasing pH concentrations. The pattern of soluble protein was observed a tendency to decrease from acidic pH eradlents. According to acidity, total DNA contents of each crop was showed a definite reduction. In conclusion, plant growth was stimulated decreasln and the chanties of total Protein Patterns and BNA contents extracted from leaves trended with stimulated acrid rain was showed seriously.

• The Korean Journal of Ecology
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• v.19 no.1
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• pp.71-80
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• 1996

The effects of simulated acid rain on the growth and interspecific competition of Echinochloa crus-galli and Digitaria sanguinalis were studied. Changes of growth in height and dry weight were examined and competition between the two species was investigated using the experimental model proposed by de Wit (1960). The experiments were carried out in the greenhouse, and test plants were germinated and grown for 4 weeks and then sprayed with simulated acid rain of pH 5.6, 4.2 and 2.8 for another 8 weeks. In de Wit replacement experiments, the variation of density and the treatment of simulated acid rain showed little effect on the interspecific competition between E. Crus-galli and D.sanguinalis. The ratio diagram, another method to reveal the interrelations between two competing species, always showed the predominance of E. crus-galli in competition, regardless of density and pH. The interspecific competition of the two species, represented by relative yield total (RYT), revealed that intraspecific competition was stronger than interspecific competition in both species.The treatment of simulated acid rain showed little effect on the growth of E. Crus-galli and D. sanguinalis. Height growth of both species did not differ from that of control (pH 5.6), but root/shoot ratio increased with the decrease in pH of simulated acid rain. Growth of tatal dry weight of E. crus-galli and D. sanguinalis was not influenced by the change of pH, except that D.sanguinalis showed a decrease in the total dry weight at pH 2.8 along with a visible sign of white spots on leaves. Physical environmental conditions can exert an effect on the interrelationships between the two species, but this experiment did not show the reversion of competition, and showed that E.crus-gilli was competitively dominant under any environmental conditions given in this study.

• Korean Journal of Environmental Agriculture
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• v.18 no.3
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• pp.245-249
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• 1999

This study was carried out to investigate the influence of artificial acid rain on the growth of soybean irradiated with the low dose gamma radiation. The growth patterns of Hwangkumkong and Bangsakong were not dependent on the acid rain treatment and the period of seed storage but the radiation dose. In Hwangkumkong, the optimal irradiation dose for the growth promotion was lower in the acid rain treatment group than the control group. The symptom of acid rain damage appeared broadly around pH 2.20, were higher in Hwangkumkong than in Bangsakong, and were more effective in the seeds of 1997 than 1995. But the damage symptom of Bangsakong was not dependent on the acid rain treatment and the irradiation of gamma radiaiton.

• Journal of Plant Biology
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• v.38 no.1
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• pp.79-86
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• 1995

Visible injury symptoms such as necrosis, chlorosis and premature senscence in the leaves of Ginkgo bloba and Pinus thunbergii treated with acid rain of pH 3.2 or below were observed. The epicuticular wax erosions were observed by SEM after exposure to acid rain of pH 2.4 and 3.2 in G. biloba and pH 4.0 below in P. thunbergii. The adaxial epidennal cells and sponge parenchyma cells were compressed, and those were distorted in the leaves of G. biloba treated with simulated acid rain of pH 3.2 or below. However, vascular tissue was intact. With increase of acidity, mesophyll cells were smaller than those of control while intercellular space in mesophyU was increased. In P. thunbergii, sponge parenchyma cells and vascular tissue except epidennis were distorted after exposure to acid rain of pH 2.4. The size change of stomata in foliar injury was not observed, but the stomatal index and size of stomatal aperture in leaves treated with acid rain increased. The stomata of injured leaf were opened in both species examined.amined.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.305-313
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• 1997

The effect of acid rain on plant isozyme response was studied with the treatment of simulated acid rain to Pinus densiflora, P. nigida and P. koraiensis for 9 months. The isozyme pattern of $\alpha$-Esterase($\alpha$-Est), Peroxidase(POD) and Glutamate dehydrogenase(GDH) were observed in the control (pH 5.6) and simulated acid rain (pH 3.5) treatment. No changes of isozyme pattern in $\alpha$-Est was observed in P. densiflora after 9 month treatment of simulated acid rain, but, two new isozymes were activated in P. nigida in the same treatment. In P. koraiensis, two new isozyme were activated but five isozymes were not activated. P. densiflora did not show any difference in POD and GDH after the treatment of simulated acid rain. P. nigida showed activation of eight and two isozymes in POD and GDH, respectively. P. koraiensis showed inactivation of 4 isozymes in POD but showed no changes In GDH.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.4
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• pp.400-406
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• 1998

To investigate the effect of simulated acid rain on the change in soil chemical properties, simulated acid rain of different pH was applied to the three soils of different texture. Simulated acid rain of pH 4.0 and 6.0 did not greatly change the soil pH, while simulated acid rain of pH 2.0 decreased greatly the soil pH. Decrease in soil pH were in the order of sandy loam > loam > clay loam, while increase in exchangeable acidity was in the order of clay loam > loam > sandy loam. Amount of nutrients leached downward due to the penetration of simulated acid rain into the soil was in the order of Ca > K > Mg. Exchangeable Al was not detected when soil acidity dropped to pH 5 and exchangeable acidity increased within a range of CEC. A total 1200mm of simulated acid rain(pH 3.0) can load $12kg\;ha^{-1}$ of $H^+$ ion, $128kg\;ha^{-1}$ of sulfur, $56kg\;ha^{-1}$ of nitrogen. The acidity of simulated acid rain pH 3.0 can be neutralized by addition of $444kg\;ha^{-1}$ of slaked lime. The amount of leached bases were equivalent to 923, 1731 and $1608kg{\cdot}ha^{-1}$ in sandy loam, loam and clay loam soil respectively.