• 자원환경지질
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• 제32권1호
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• pp.43-51
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• 1999

In order to remediate hazardous waste site, a process of electrokinetically purging chemicals from saturated soil is examined by laboratory experiments. Electrokinetic soil remediation is one of the most promising soil decontamination processes that habe igh removal efficiency and time-effectiveness in low-permeability soils such as clay. Being combined with several mechanisms-electromigration, elec troosmosis, diffusion and electrolysis of water, electrokinetic soil processing can remove non-polar organics as well as ionic contaminants. The objectives of this study are; 1) the exploration of the feasibility of electrokinetic soil processing on the removal of heavy metals, 2) the investigation of applicability to the tailing-soils in aban doned mining area, 3) the examination of effects of soil pH and conductivity on the transport phenomena of elements in soils, and 4) the investigation of the applicability of the ionexchange membrance to the efficient collection of heavy metals removed from contaminated soils. With the result of this study, it is suggested that the removal efficiency is significantly influenced by applied voltage & current, type of purging solutions, soil pH, permeability and zeta potentials of soil. Although further study should be needed, it is possible to collect removed heavy metals with ion-exchange membrance in cathode compartment.

• Nuclear Engineering and Technology
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• 제36권4호
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• pp.304-315
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• 2004

The ageing effects of radionuclides in radioactive soil on remediation using the electrokinetic method were analyzed. Comparative experiments were conducted for the reactive soil around a TRIGA research? reactor contaminated with $^{137}Cs\;and\;^{60}Co$ for 15 years and the non-reactive soil that was intentionally contaminated with $Cs^+\;and\;Co^{2+}$ for 3 days. It was observed that because of an aging effect on $^{137}Cs$, the efficiency of removing it decreased. $H_{2}SO_4$ used as an additive to increase the removal efficiency showed a higher removal capability than other chemicals for both $^{137}Cs\;and\;^{60}Co$. The efficiency of removing radionuclides from the radioactive soil in the column was proportional to the capability of the added chemical to extract radionuclides. It took 10 days to achieve a $54\%$ removal of $^{137}Cs$ and a $97\%$ removal of $^{60}Co$ from the soil. The volume of the soil wastewater discharged from the soil column by the electrokinetic method was $20\%$ below that for soil washing.

• The Plant Pathology Journal
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• 제37권6호
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• pp.596-606
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• 2021

Soil-borne diseases are the major problems in mono cropping. A mixture (designated LTM-m) composed of agricultural wastes and a beneficial microorganism Streptomyces saraceticus SS31 was used as soil amendments to evaluate its efficacy for managing Rhizoctonia solani and root knot nematode (Meloidogyne incognita). In vitro antagonistic assays revealed that SS31 spore suspensions and culture broths effectively suppressed the growth of R. solani, reduced nematode egg hatching, and increased juvenile mortality. Assays using two Petri dishes revealed that LTM-m produced volatile compounds to inhibit the growth of R. solani and cause mortality to the root knot nematode eggs and juveniles. Pot and greenhouse tests showed that application of 0.08% LTM-m could achieve a great reduction of both diseases and significantly increase plant fresh weight. Greenhouse trials revealed that application of LTM-m could change soil properties, including soil pH value, electric conductivity, and soil organic matter. Our results indicate that application of LTM-m bio-organic amendments could effectively manage soil-borne pathogens.

• 한국환경농학회지
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• 제6권2호
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• pp.1-11
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• 1987

수도용(水稻用) 유기인계(有機燐系) 살충제중에서 조제형태(粗劑形態)로 널리 사용되는 Diazinon제와 Dursban제의 담수토양중(湛水土壤中)에서의 경시적(經時的) 분해(分解)정도를 비교(比較)하고, 아울러 살균(殺菌)과 비살균(非殺菌)토양을 비교하므로서 토양미생물(土壤微生物)에 의한 분해효과(分解效果)를 실험하였다. 아울러 두 약제의 분해대사산물을 GC/MS로 확인하였으며 중요한 결과는 아래와 같다. 1. 항온기(恒溫器$(30{\pm}1^{\circ}C)$)내에서 담수상태(湛水狀態)로 처리한 Diazinon제와 Dursban제의 경시적 변화는 비살균토양(非殺菌土壤)에서 보다 살균토양(殺菌土壤)에서 약 3배(培) 정도 지연되었으며, 따라서 미생물에 의한 분해를 확인할 수 있었다. 2. Diazinon제의 상용농도에서의 반감기는 2.2일이었으며, Dursban 제는 10.8일이었다. 상용농도의 3 배량 고농도 처리에서는 두 약제 모두 평균 1일정도 분해가 지연되었다. 3. Diazinon의 분해대사산물(分解代謝産物)로는 가수분해산물인 0, 0-diethyl phosphorothioate 와 이 화합물의 이량체(二量體)인 sulfotep, 그리고 monooxygenase 에 의한 분해대사물인 Diazoxon, 0,0-diethyl-0-[2-(1-hydroxy-1, 1-dimethyl)-6-methyl]-pyrimidinyl phosphorothioate 그리고 2-isopropyl-6-methyl-pyrimidine-4-one 이 확인되었으며, Dursban 제의 대사산물로는 0, 0-diethyl phosphorothioate 만이 확인되어 주로 esterase 에 의한 분해가 주대 대사경로라고 밝혀졌다.

• 한국환경농학회지
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• 제42권3호
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• pp.184-192
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• 2023

Microplastics are generated by the breakdown of plastic wastes in agricultural soil and residual pesticides in agricultural soil can adsorb on microplastics. In this study, the sorption characteristics of procymidone (PCM) and one of its metabolites, 3,5-dichloroaniline (DCA), on low-density polyethylene (LDPE) and polyvinyl chloride (PVC) microplastics were investigated. The sorption and desorption tests were carried out for 72 h using LDPE or PVC microplastic films to study the sorption isotherms of PCM and DCA and kinetics for sorption and desorption of PCM. The results show that the sorption data of PCM and DCA were better described by the Freundlich isotherm model (R²=0.7568-0.9915) than the Langmuir isotherm model (R²=0.0545-0.5889). The sorption potential of PVC for both PCM and DCA was greater than that of LDPE. The sorption data of PCM on PVC and LDPE were fitted better to the pseudo-second-order kinetic model than the pseudo-first-order kinetic model. The PCM sorption on LDPE was about three times faster than that on PVC. Both microplastic films released the sorbed PCM back to water, and more PCM was released from PVC than LDPE, but the desorption rate was faster with LDPE than PVC. Overall, the results show that different microplastics have different sorption characteristics for different chemicals. Also, the sorbed chemicals can be released back to environment suggesting the potential of contaminant spread by microplastics. Thus, the management practices of microplastics in agricultural soil need to consider their interaction with the chemical contaminants in soil.

• 한국환경농학회지
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• 제15권1호
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• pp.105-115
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• 1996

In this paper, we reviewed the degradation factors of diazinon which was known to be easily degraded by soil microorganisms and lost of its activity. Under submerged soil condition, the contribution of microorganisms to diazinon degradation was about 40% and these microorganisms preferred soil humus as substrates to diazinon itself. The effect of monooxygenase activity in submerged soil was more important than esterase activity on diazinon degradation and these enzymes were inhibited by several chemicals such as piperonyl butoxide(PBO), EPN and tricyclazole. From these results, new formulation type of diazinon (PBO and triphenyl phosphate were added to commercial diazinon formulation by 0.1% respectively.) and diazinon mixture formulation (diazinon was mixed with EPN, tricyclazole and carbofuran in equal amount) were prepared. The new formulation type of diazinon showed better insecticidal activity by 12% and more delayed diazinon degradation in ten days than commercial diazinon.

• 한국산림과학회지
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• 제20권1호
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• pp.51-60
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• 1973

The trend and achievments of soil erosion control research in Japan were investigated through observation tours and reference work and following facts were found to be important aspects which should be considered in the soil erosion control research program in Korea. Experiments on forest and water relations, and ground water phenomena at the water source zone in Tokyo University. Studies on land-slides and erosion control dam in Kyoto University. Studies on mud-flow and snow avalanches in Hokkaido University. Studies on sanddune fixation and disaster damage prevention forests in Kyushu University. Studies on forest denudations in Nagoya University. Studies on Greening-works and soil erosion prevention chemicals in Tokyo Agriculture University. Training on planning of erosion control works and prevention of disaster damages in Forest Research Institute. Experiments on soil erosion phenomena and infiltration in Tohoku Branch, FRI. Experiments on erosion and surface stratum failure of steep slopes and their prevention methods in Railway Technical Research Institute.

• 한국잔디학회:학술대회논문집
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• 한국잔디학회 2004년도 제17차 한국잔디학회 정기총회 및 춘계학술발표회
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• pp.24-31
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• 2004

본 실험은 잔디에 아미노산 비료를 시비하였을 때, 잔디의 생육과 토양에 미치는 영향에 대해 조사하였다. 토양의 화학성을 비교한 결과 아미노산 액비 처리구에서의 토양 중 질소 이용율이 대조구에 비해 증가하였다. 작물의 화학성을 비교한 결과 아미노산 액비 처리구에서 질소 함량, 고토 함량 및 엽록소함량이 대조구에 비해 높았고, 잔디의 생체중과 건물중이 증가하였다 본 실험을 통해 아미노산 액비를 시비할 경우 잔디의 토양 중 질소 이용율이 증가하여 잔디의 생육에 도움이 되고 있음을 알 수 있었다.

• 한국토양비료학회지
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• 제36권3호
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• pp.127-133
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• 2003

토양미생물의 생태적 특성을 평가하기 위해 화강암, 석회암 및 현무암을 모재로 한 12개의 토양통의 미생물적 특성을 조사하였다. 토양미생물상은 토양화학성과 유의한 상관관계를 보였는데, 특히 토양 pH는 형광성 슈도모나스와, 토양 EC는 방선균, 사상균, 중온성 Bacillus 및 호알카리성균과 정의 관계를 보였다. 포자형성균인 Bacillus는 화강암과 현무암에 비해 석회암토양에서 높은 균수를 보였으나, 그람음성균은 모암간에 비슷한 수준을 유지하였다. 화강암유래 토양에서는 Burkholderia, Pseudomonas, Ralstonia가, 석회암토양에서는 Pseudomonas, Burkholderia, Phyllobacterium가, 현무암토양에서는 Burkholderia속이 우점적으로 분포하고 있었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권1호
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• pp.34-44
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• 2021

Acid mine drainage (AMD) resulting from pyrite oxidation in mining areas, subsequently leads to soil acidification accompanied by lowering pH and high concentration of metals and metalloids in its surrounding environment. Regarding to this, the microbial amelioration has been considered as a promising option for a more cost-effective and eco-friendlier countermeasure, compared to the use of alkaline chemicals. This study was aimed to evaluate influencing factors in microbially-mediated amelioration of acidic soil spiked by simulated AMD. For this, microcosm experiments were conducted by acid-neutralizing bacterial consortium (dominated by Klebsiella sp. and Raoultella sp.) under the various conditions of AMD spikes (0-2,500 mg SO42-/L), together with acidic mine soil (0-100 g) or sphagnum peat (0-5 g) in the 200 mL of nutrient medium. The employed bacterial consortium, capable of resisting to high level of sulfate concentration (up to 1,500 mg SO42-/L) in low pH, generated the ammonium while concomitantly reduced the sulfate, subsequently contributing to the effective soil stabilization with an evolution of soil pH up to neutral. Furthermore, it demonstrates that suitable condition has to be tuned for successful microbial metabolism to facilitate with neutralization during practical application.