• The Korean Journal of Pesticide Science
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• v.2 no.2
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• pp.59-67
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• 1998

토양중 침투성 살충제 carbofuran과 제초제 petilachlor의 용탈행적을 구명하기 위하여 물리화학적 성질이 상이한 2종의 논토양으로 충전된 토양 column (내경 5cm ${\times}$ 길이 30cm)에 $^{14}C$-표지 화합물을 각각 처리한 후 벼 (Oryza sativa L.)를 생육시키면서 벼를 심지 않은 경우를 대조구로 하여 8주 동안 주당 95.2 ml씩 용탈시켰다. Carbofuran의 경우 토양 column에서 용탈된 $^{14}C$ 방사능의 양은 벼를 재배하지 않은 토양 A와 B에서 각각 총처리 방사능의 74.8와 92.3%였으며, 벼를 재배한 토양에서는 각각 45.1%와 69.7%였다. 반면에 petilachlor의 경우 벼를 재배한 토양 column에서는 각각 총처리 방사능의 2.4%와 5.0%가 용탈되었으며, 벼를 재배한 경우는 각각 3.1%와 8.2%가 용탈되었다. 토양에 처리한 [$^{14}C$]화합물 모두 벼의 생육유무에 관계없이 양이온치환용량, 유기물 및 점토의 함량이 적은 토양 B에서 $^{14}C$ 방사능의 용탈이 증가되었다. 토양 column중 carbofuran의 이동성은 매우 높은 반면에 petilachlor는 매우 낮았으며, 이는 그들의 토양흡착과 수용성에 기인된 것으로 판단된다.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.43-52
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• 1988

One-year-old seedlings of Ginkgo biloba were treated with various simulated acid rains(pH 2.0, pH 3.0, pH 9.0 and pH 5.0) to examine the effects of simulated acid rain on the chemical properties of the tested soil. The seedlings were grown in a pot($4500cm^3$)containing one of three different soils(nursery soil, mixed soil and sandy soil). Simulated acid rain was made by diluting sulfuric and nitric acid solution($H^1SO^4$ : $HNO^3$ =3 : 1, V/V) with tap water and tap water(pH 6.4), and treated by 5mm each time for three minutes during the growing seasons(April to October 1985). Acid rain treatments were done three times per week to potted seedlings by spraying the solutions. The chemical properties of potting media were compared among three soil types as well as among the various pH levels. The results obtained in this study were as follows : 1. Exchangeable calcium and magnesium contents and base saturation of the soil decreased with decreasing pH levels of acid rain, and their decreasing rates were as follows : sandy soil was the highest, followed by mixed and nursery soils, However, exchangeable aluminum content rather increased as the pH levels decreased. 2. Available phosphate in the soil decreased as the pH levels of acid rain decreased. Its content increased in nursery soil, compared with those before acid gain treatment, Gut decreased in mined and sandy soils. 3. Soil sulfate and nitrate contents increased remarkably as the pH levels decreased, and the only significant difference in the sulfate was found among the pH levels. Soil sulfate content was the highest in nursery soil, followed by mixed and sandy soils.

• Current Research on Agriculture and Life Sciences
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• v.24
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• pp.43-47
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• 2006

The soils of plastic film houses in which intensive cultivation takes place suffer from the serious problems such as severe salinity and accumulation of heavy metals etc. The objective of this research was to examine the change in soil properties with repeated cucumber cultivation under plastic film house at Gunwi-Gun area. The soils were classified mainly to Danbuk and SinJung series. Clay content is lower in the soils of plastic film house than in the field soil. Available $P_2O_5$ and exchangeable cations were accumulated at the level higher than the optimum range. The content of extractable heavy metals were higher in the soils of plastic film house than in those of the field. For optimum yield, much attention should be paied to the management of soils by the pre-soil survey.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.3
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• pp.241-248
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• 1995

This experiment was conducted to obtain basic information for the management of soil and fertilization for plastic-house soil cultivated Khwari green pepper in Dang Jin area of Chung Nam Province. The range of pH with highest frequency for 36 sites investigated was 6.1~6.5, OM 1.6~2.5%, available phosphorous 601~800mg/kg, CEC 12.1~14.0 c mol/kg, clay 16.1~18.0% and below 2.0ds/m for electical conductivity of soil. Fesh fruit weight of green pepper showed very high significant positive correlation with organic matter, clay content and cation exchange capacity, while negaive correlation with electrical conductivity. Electrical conductivity showed highly significant negative correlation with CEC, clay content and organic matter in soil, respectively. To decrease below 2.0 dS/m of electrical conductivity in plastic-house soil, the content of clay and organic matter could be maintained at above 1.8% and 2.3%, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.177-182
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• 1991

This study was carried out to clarify the effects of grassland afforestation on some chemical properties of the Japanese ceder(Cryptomeria japonica) forest soil in Cheju Island. The following results were obtained in this study ; 1. T-C, T-N, exch. cations and base saturation in the surface soil(0~10cm) decreased sharply from planting to crown closure. However, after crown closure, exch. Ca and Mg increased considerably. On the other hand, there were no definit changes below surface soil. 2. In vertical distribution of chemical properties, T-C, T-N, exchangeable acidity and exch. cations decreased with soil depth. Especially, exch. Ca and Mg of surface soil in closed stand show a higher value than that in open stand, but there were no variation below surface soil. 3. In closed stand, the amounts of exch. Ca, Mg and K were 1.8 times, 1.6 times and 1.5 times greater than those in open stand. There was no significant difference between open and closed stand in T-C and T-N. 4. The ratios of the amounts of nutrients in surface soil to those in mineral horizons(ha, 50cm) between the open and closed stand showed 30% and 50% for exch. Ca, 30% and 40% for exch. Mg, 38% and 38% for exch. K, respectively.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.50-61
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• 2018

The current study aimed to review the research trends on forest liming by age, country, and research topics, and seeks to summarize the effects of forest liming on soil, vegetation and water system in forest ecosystems. The recent goals of forest liming have been changed in response to changes in the acid deposition, and related studies have been mainly carried out in Europe and North America, where there is noted a massive forest decline, which was subsequently caused by acid rain. Most forest liming studies are noted to have focused on soil responses, however, the number of studies on the responses of vegetation and water system according to a literature review on the subject were relatively small. Meanwhile, forest liming influenced whole forest ecosystems through interaction between the soil, vegetation and water system as associated with the relevant regions. The changes in soil pH, base saturation, and cation exchange capacity by forest liming were noted as different depending on the soil layer and elapsed time after liming. The responses of vegetation to forest liming were shown in above- and below-ground plant growth and plant nutrient concentration, and also were noted to have varied depending on the available regional plant species and noted specific soil conditions. The chemical properties of the water system were changed similarly to those in the soil, leading to notable changes as seen in the planktons and available fish species in the region. Finally, these results could be used to plan further studies on forest liming, which would significantly benefit regional studies to promote the preservation of the species noted for protection in the region.

• Plant Journal
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• v.12 no.1
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• pp.37-43
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• 2016

The corrosivity evaluations on soil surrounding the buried steel piles under manufacturing plants. It was proven that the soil structure of this sample area is composed of several soil layers, and that each layer show the different corrosivity. The predicted average corrosion rates of some layers are about 0.33mm/y, which is over than the general corrosion rate, 0.01-0.02mm/y.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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• pp.69-73
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• 1999

The study was performed to examine the elimination capacity of impurity on the fiberglass wicks to exert a suction of Passive capillary samplers (PCAPS) on soil water. This impurity affects the capillary properties of the wick and the chemical properties of the samples collected. To determine the need, capillary rise and moisture contents were measured after the wicks were cleaned by four methods : combustion, acetone extraction, detergent washing, and uncleaning. The wicks were made with fibers produced by PPG Industries and Manville Company, U.S.A. Results showed that wicks made from PPG fibers lost up to 3.4% of original mass during combustion while Manville fiber wicks lost only up to 0.6%. These losses are assumed to have been due to combustion of organic compounds applied by the manufacturers. All cleaning methods had higher capillary rise than obtained with uncleaning method Combustion at 40$0^{\circ}C$ for 4 hours was the best cleaning method. removing 98 to 100% of impurities.

• Korean Journal of Organic Agriculture
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• v.8 no.3
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• pp.131-146
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• 2000

This experiment was focused on finding out the potential problems in organic farming system, which is recently emphasized on the produce of horticultural crops due to the serious environmental deterioration. Thus, in this study, the effect of the application of organic farming materials in soil on plant growth and components of chinese cabbage and the soil Physicochemistry property were compared with conventional culture. The results were summarized as follows : 1. The effect of soil chemical properties after application of organic farming materials, The amounts of pH and O.,M. in N, P, K treated plot were few of change, To the contray, fermentation compost and microorganisms fermentation compost treated plot were some increase, Amount of P$_2$O$_{5}$ , Ca and increase in comparison with the N, P, K treated plot, Specially chicken manure+ microorganisms fermentation compost treated plot was the highest. 2. Change of soil microbial after application of organic farming materials, The number of bacteria and actinomycetes in N, P, K treated plot were appeared definite direction, to the fermentation compost and microorganisms fermentation compost treated plot showed the increased tendency, specially, chicken manure+ microorganisms fermentation compost treated plot was the highest, 3. The growth characteristic of chinese cabbage after application of organic farming materials was superior in order of chemical fertilizers plot> microorganisms fermentation compost plot> fermentation compost plot. It shows the NO$_3$$^{[-10]}$ accumulation in chinese cabbage was higher in the outer leaves than in the inner leavess. It was some lower in the microorganisms fermentation compost plot, it was the highest at chemical fertilizers plot , all inner and outer leaves.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.320-326
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• 1997

In order to elucidate the degradation characteristics of the herbicide imazapyr in soil, mineralization to $^{14}CO_2$and adsorption were investigated using eight types of soils with the different physico-chemical properties. The results obtained were as follows: 1. During the incubation period of 12 weeks after the treatment of imazapyr, the amounts of $^{14}CO_2$ evolved from 8 types of soils with different properties ranged from 1.5 to 4.9% of the originally applied $^{14}C$ activities. Soil C, G, and H with low pH and high organic matter showed low $^{14}CO_2$evolution, whereas soil B and D with high pH and low organic matter did high $^{14}CO_2$ evolution. 2. Time for reaching the equilibrium concentrations in the adsorption experiment of imazapyr in soils was about 3 hours at $25^{\circ}c$ in soil C, D, G, and H. Imazapyr was adsorbed in the range of 0.25${\sim}$28.32% in soils with different physico-chemical properties. Among the soil parameters, organic matter content was the most influential in imazapyr adsorption on soil. The Freundlich adsorption coefficient $(K_f)$ increased 5.5 to 25.6 times as organic matter content increased 2.0 to 21.3 times. Hence it seems that the extent to which soil organic matter contributes to imazapyr adsorption is greater than that of clay mineral. $K_f$ values for the soils tested were 0.44, 0.08, 0.65, and 2.05 in soil C, D, G, and H, respectively. In all the soils tested, $K_f$ values had a strong resemblance to K_$K_d$.