• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.153-156
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• 2000

본 연구에서는 지하수내에서의 오존의 거동과 오존산화공정에 의한 디젤의 분해를 조사하였다. 오존의 초순수와 지하수내에서의 반응은 모두 2차 분해반응속도식을 나타냈고, 초순수와 지하수내에서의 반감기는 각각 평균 37.5분, 14.7분으로 계산되었다. 지하수내에서 오존의 자가분해반응속도가 더 빠른 것으로 나타났는데 이는 오존이 지하수내에 존재하는 각종 유기·무기물질들과의 빠른 반응때문이라고 생각된다. 오존의 TCE, PCE 그리고 디젤의 빠른 제거효율을 통하여 디젤로 오염된 지하수를 처리하는데 있어서 오존산화공정은 효과적으로 적용될 수 있을 것이라 판단된다.

• Journal of Radiation Protection and Research
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• v.17 no.2
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• pp.15-23
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• 1992

Transport behaviors of Cs-137 and Sr-90 were analyzed and ingestion doses were calculated using dynamic model for rice field-rice-man pathway. Cs-137 binding strongly to soil remain longer in rice field than Sr-90. Foliar deposition on rice plant during growing period is the main contamination mechanism.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.272-278
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• 2006

Movement of pesticides applied for crop protection to the non-target environmental compartments has increasingly concerned in recent. A special review on groundwater leaching potential of pesticides registered in Korea was done by using the data submitted on half-life and adsorption of the pesticides in/on soil. Groundwater ubiquity score(GUS) of pesticides as a leaching potential was calculated by using domestic trial data on pesticide half-life in paddy or upland soils and Koc data bases of Oregon State University (OSU), British Pesticide Safety Directorate and Sweden. Of total 382 pesticides reviewed, domestic half-lives of 107 pesticides were for paddy soil and 297 pesticides for upland soil. And total 317 Koc values were collected 148 pesticides from OSU DB and 276 pesticides from UK/Sweden DB. Very highly leachable pesticides were 18 and highly leachable pesticides were 44 among 313 pesticides classified by GUS.

• Applied Biological Chemistry
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• v.38 no.3
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• pp.263-268
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• 1995

A study was undertaken to compare degradation patterns of carbofuran in soils between submerged and upland moisture conditions [$3-^{14}C$]Carbofuran was treated in each soils at the rate of 1.0 mg/kg (87.8 kBq $^{14}C/50g$ soil) and the time-course analysis for distribution of radioactivity and degradation products were conducted. Differences in the pathway and rate of carbofuran degradation in soils were observed between submerged and upland moisture conditiona major degradation being hydrolysis at 7-C position and oxidation at 3-C position, respectively. Carbofuran showed less persistence in soils of higher moisture contents A significant portion, $24{\sim}39%$ of the total radioactivity, resided in soils as nonextractable residues at 60 days after treatment The nonextractable radioactivity was mainly located in soil organic matter, fulvic acid, humic acid and humin factions Gel filtration chromatography confirmed the incorporation of carbofuran and its degradation products into the organic matter.

• Korean Journal of Environmental Agriculture
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• v.6 no.2
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• pp.1-11
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• 1987

The degradation of two chemicals seem to be clearly affected by soil microbial activity in submerged soil $conditions(30{\pm}1^{\circ}C)$. The Active ingredient of Diazinon disappeared about 5 times faster than that of Dursban. By Applying 300% higher concentrations of both chemicals. under the above soil conditions, however, degradation was retarded by about one day. Some of the metabolites of Diazinon were as follows: 0.0-diethyl phosphorothioate and sulfotep as hydrolytic products, and diazoxon, 0.0-diethyl-0-[2-(1-hydroxy-1, 1-dimethyl)-6-methyl]-pyrimidinyl phosphorothioate and 2-isopropyl-6-methyl-pyrimidine-4-one as degradation products of monooxygenase. But 0. 0-diethyl phosphorothioate was the only methabolite of Dursban.

• Korean Journal of Environmental Agriculture
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• v.15 no.4
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• pp.488-493
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• 1996

This study was conducted to find out the residual aspect and the effect of quizalofop-ethyl on microorganisms used to control broad-leaf weeds at Yeongok soil series, the experiment field, Chonnam R.D.A. and Namwon soil series, the experiment field, Jeju R.D.A. More than 60 percent of quizalofop-ethyl treated in soil was degraded within 7 days. The degradation of quizalofop-ethyl in soil increased rapidly with incubation temperature. The half-life of quizalofop-ethyl in soil was 15 days(Yeongok series) and 16 days(Namwon series). The number of microorganisms in soil treated with quizalofop-ethyl decreased prominently with incubation time. But the number of Fusarium did not reduce in comparison with that of other soil microorganisms. Therefore, it was thought that the decomposition of quizalofop-ethyl in soil was affected by $Fusarium^2$.

• Korean Journal of Environmental Agriculture
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• v.9 no.1
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• pp.1-8
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• 1990

The effects of soil environmental conditions on the degradation rates of fenitrothion(O-O-dimethyl O-4-nitro-m-tolyl phosphorothioate) in soils under flooded conditions were examined in the laboratory. Fenitrothion was degraded rapidly and the half life period was within 4 days. Furthermore the degradation was mere rapid under flooded conditions than under upland conditions. The decomposition rate was varied with soils and soil temperatures. Fenitrothion degraded more slowly at 30ppm than at l0ppm. Repeated applications of fenitrothion in soils accelerated the degradation rates. The degradation remarkably increased with amendment of rice straw. However, degradation rates ,were virtually unaffected by the addition of the mixed-fertilizer, the fungicide IBP and the herbicide butachlor. The population of fenitrothion-degrading microbes, which were counted by MPN method, always corresponded with the degradation rates in the soils.

• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.341-346
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• 1997

The degradation of fungicide oxadixyl in soil amended with manure, chemical fertilizers, heavy metals and detergent was studied. The degradation of oxadixyl in the soil was slow, but became to be fast after the lag phase of about 14 days. The half-life was 10.5 days. The degradation rate was accelerated largely by the amendment of manure. Potassium also promoted the degradation rate but nitrogen and phosphate did not. The heavy metals inhibited the degradation rate, in order of Ni, Cd, Cr, Cu, and Zn. The degradation rate was declined greatly with the addition of synthetic detergent. The microbial biomass and the respiration rate in the soil were increased by the amendment of manure and chemical fertilizers, but decreased by the addition of heavy metals and cleaner. The degradation rate of oxadixyl was positively correlated with the microbial biomass and the respiration rate.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.14-20
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• 1988

The effect of polyethylene film(P.E.) mulching on the degradation of alachlor(N-methoxymethyl-2, 6-diethyl ${\alpha}-chloroacetoanilide$), pendimethalin(3, 4-dimethyl-2, 6-dinitro-N-l-ethylpropylanilide) and diphenamid(N,N-dimethyl-2, 2-diphenylacetamide) in red pepper, peanut, and sesame fields was investigated. In soils under the non-mulching condition the half-lives of alachlor, pendimethalin and diphenamid were 3, 37 and $24{\sim}46$ days, respectively. However, the half-lives of those under the P.E. mulching condition were longer than under the non-mulching condition. The differences in the half-lives between P.E. mulching and non-mulching conditions were about 30 days for pendimethalin and from 20 to 90 days for diphenamid. However, the half-life of alachlor was hardly affected by P.E. mulching. Pendimethalin and alachlor were not detected in the harvasted red peppers, peanuts and sesame under P.E. mulching and non-mulching conditions. But, the residue of diphenamid in peanuts was 0. 147 ppm under the P.E. mulching condition and 0.071 ppm under the non-mulching condition, and the residue of diphenamid in sesame was 0.022 ppm under the P.E. mulching condition and 0.129 ppm under the non-mulching condition. The amounts, however, were below the tolerance limits for pesticide residue.

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.286-290
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• 2002

This work has been conducted to investigate the behavior of pesticides in ginseng(Panax ginseng C. A. Meyer) cultivation environment, with a fungicide procymidone as a model pesticide. Procymidone adsorption on ginseng cultivating soil was studied and persistency of procymidone in soil was monitored in indoor incubation experiments at 25$^{\circ}C$ and 10$^{\circ}C$. The soil adsorption coefficients($K_{oc}$) of procymidone were in the range of 513$\sim$743 suggesting the mobility of procymidone in soil is relatively low. Procymidone showed higher persistency in soil under indoor incubation condition than outdoor field condition. The half lives estimated from the first order reaction kinetics were 248 days and 330 days at 25$^{\circ}C$ and 10$^{\circ}C$, respectively.