• 한국물환경학회지
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• 제29권4호
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• pp.489-496
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• 2013

지하수계의 근간을 이루는 토양시스템은 유기화학물질에 오염되기 쉬운 환경에 놓인다. 이러한 토양의 유기화학물질 침투 거동을 평가하기 위해 점토, 실트 및 모래로 구성된 실험장치에 유기화학 물질 이동실험을 하였다. Chloroform, 1,1,1-trichloroethane 및 trichloroethylene은 토양을 통해 이동이 쉽게 이루어지며, 투과된 오염물질의 질량은 전체 질량의 최소 4.6에서 최대 19.2% 범위를 보였다. Tetrachloroethylene Tetrachloroethylene, 1,2-dichlorobenzene 및 1,3-dichlorobenzene은 토양 흡착에 의해 이동이 지연되어졌으며, 각 매개체의 0.6 ~ 4.8%가 표층에서 여과되는데 이용되었다. Carbon tetrachloride는 거의 투과되지 못하였고, 단지 0.1 ~ 0.4% 질량만이 침투거동에 도달하였다. Bromoform은 거의 투과되지 못하였으며, 브롬화(Br) 화합물의 중간 전환물질로도 확인되었다. 유기화학오염물들의 이동은 토양입자크기 및 수리전도도 등에 따라 달라진다고 여겨지나 본 연구에서는 유기화학오염물들의 이동은 점토, 실트 토양보다 모래 토양에서 더욱 빠르게 나타났다.

• Applied Biological Chemistry
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• 제27권
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• pp.56-67
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• 1984

As in many other country, the use of organic matter in Korea has long history. Farmers understand the value of organic matter as the source of plant nutrient and soil improving agent in general. Since 50 years ago, the sources of organic matter in paddy soils were compost, rice and barly straw, green manure, animal waste, fish and beancake, etc.. Application of green manures such as vetch and chinese milk vetch showed no significant effect on the yield of brown rice in paddy soil. On the other hand, the effects of compost and rice straw showed more significant on the yield of brown rice in paddy soil. Application of rice straw in rice cultivation is commonly made at different times between harvest, early spring and several weeks before transplanting. Considering the suitable paddy soil for application of rice straw under well to moderately well drained soil, the yield was pronounced more than poorly drained soil. Based on laboratory and field experimants, application of rice straw promoted the decrease of oxidation-reduction potential in well to moderately well drained soil. This results to be enhanced the release of some mineral nutrients,. such as potassium, calcium, silicon, and increase of availability of soil phosphorus. In the field experiments, results obtained from nitrogen fraction on the immobilization-mineralization of the tracer nitrogen applied in paddy soil,the amount and index of organic nitrogen incoporated in soil was more pronounced in rice straw application than control. Rice straw and its transformation products incoporated in the soil, provided the inflow of energy necessary to maintain heterotrophic microbes activities. Rice straw and its transformation products, especially soluble carbohydrate, enhanced the population of free-living heterotrophic $N_2$ - fixing microbes. Moreover, rice straw and its transformation products in paddy soil, enhanced the activities of soil enzymes such as dehydrogenase and urease.

• 한국토양비료학회지
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• 제47권6호
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• pp.486-490
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• 2014

This study was conducted to investigate the effect of carbonized biomass from crop residues on soil carbon storage during soybean cultivation. The carbonized biomass was made by field scale mobile pyrolyzer. The treatments consisted of control without input and three levels of carbonized biomass inputs as $59.5kg10a^{-1}$, C-1 ; $119kg10a^{-1}$, C-2 ; $238kg10a^{-1}$, C-3. Soil samples were collected during the 113 days of experimental periods, and analyzed soil pH and moisture contents. Soil carbon contents and soybean yield were measured at harvesting period. For the experimental results, soil pH ranged from 6.8 to 7.5, and then increased with increasing carbonized material input. Soil moisture contents were slightly higher by 0.1~1.5% than the control, but consistent pattern was not observed among the treatments. Soil carbon and organic carbon contents in the treatments increased at 24 and 15% relative to the control at 15 days after sowing, respectively. Loss rate of SOC (soil organic carbon) relative to its initial content was 7.2% in control followed by C-1, 6.8%> C-2, 3.5%>C-3, 1.1% during the experimental periods. The SOC change rate decreased with increasing carbonized biomass rate. It was appeared that soybean yields were $476.9kg10a^{-1}$ in the control, and ranged from 453.6 to $527.3kg10a^{-1}$ in the treatments. However, significant difference was not found among the treatments. It might be considered that the experimental results will be applied to soil carbon sequestration for future study.

• 한국습지학회지
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• 제24권2호
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• pp.69-82
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• 2022

본 연구는 상시 담수 상태의 복합생태 논습지에서 유기농 벼-큰징거미새우 복합생산 조건 시 1) 논습지 토양 화학성 및 세균 군집 특성을 파악하여 토양 화학성과 세균 간의 상관관계를 분석하고, 2) 유기농 벼 단작 토양과 관행 벼 단작 토양의 세균 군집과 비교하여 유기농 복합생태 토양의 미생물 다양성을 비교 분석하는 것이다. 토양 화학성의 경우 유기농 복합생산 운영 기간이 길수록 유효인산과 유기물 함량이 증가한다. 모든 토양 시료에서 문(Phylum) 수준의 세균 분석 결과 9개의 주요 문이 분포되어 있으며, 모든 토양 시료에서 Proteobacteria가 우점하고 있다. 속(Genus) 수준 분셕 결과 37개의 주요 속이 분류되었으며, 벤다이어그램 분석 결과 모든 토양 시료에 존재하는 250개의 OTU가 분류되었고, 유기농 벼재배 토양에 특화된 561개의 OTU가 관찰되었다. 주좌표분석 결과 관행 벼 단작 토양의 세균 군집과 비교하여 유기농 벼 단작 토양과 유기농 복합생태 논습지 토양의 세균 군집 간 유사도가 높은 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권5호
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• pp.732-739
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• 2009

Pig slurry is a good soil amendment not only because of its high organic matter content, but also because of its ability to provide various nutrients. The objective of this study was to estimate the influence of raw and processed pig slurry application on pot soil over chemical fertilizer and non-amended control soil. Change in the chemical parameters (pH, organic matter (OM), organic carbon (OC), macro and micronutrients) and microbial mass of the treated soils were monitored over 30 to 90 days. Pot soil was treated with the recommended dose of pig slurry and chemical fertilizer, and was sampled after 30, 60 and 90 days of incubation. The least significanct difference (p<0.05) was observed on Fe, Cu, Zn, available P and K between treatments. All treatments increased N, P and K content and microbial mass of soil over control soil. Interestingly, no significant effects were detected on OM, OC, total bacteria, actinomycetes and fungi mass in soil irrespective of treatments given. However fungal and bacterial counts, as well as available nutrients, were found to be higher in processed slurry (PS)-treated soil compared to other soils. In general a significant correlation existed between the fungal count and OM, OC, Zn, T Kjeldahl N (TKN), available P and K of soil. A strong negative correlation was observed between pH and Fe in soil. This study clearly demonstrated that the use of processed manure as a fertilizer could be a key for sustainable livestock agriculture.

• 한국유기농업학회지
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• 제19권spc호
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• pp.190-193
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• 2011

Organic and chemical fertilizer amendments are an important agricultural practice for increasing crop yields. In order to maintain the soil sustainability, it is important to monitor the effects of fertilizer applications on the shift of soil microorganism, which control the cycling of many nutrients in the soils. Here, culture-dependent and culture-independent approaches were used to analyze the soil microorganism and community structure under six fertilization treatments, including green manure, rice straw compost, rapeseed cake, pig mature compost, NPK +pig mature compost, NPK and control. Both organic and chemical fertilizers caused a shift of the cultural microorganism CFUs after treatments. Bacterial CFUs of the organic fertilization treatments were significantly higher than that of chemical fertilization treatments. The DGGE profiles of the bacterial communities of the samples showed that the green manure treatment was a distinct difference in bacterial community, with a greater complexity of the band pattern than other treatments. Cluster analyses based on the DGGE profile showed that rice straw compost and pig mature compost had a similar banding pattern and clustered together firstly. Rapeseed cake, NPK, NPK +pig manure compost and control clustered together in other sub-cluster and clearly distinguished from green manure.

• 한국환경농학회지
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• 제27권3호
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• pp.279-284
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• 2008

We investigated whether carboxylate exudation of Brassica pekinensis Rupr. was affected by nitrate deposition from simulated acid rain. A gas chromatographic (GC) analysis was employed for the determination of low molecular weight organic acids (LOA) in rhizosphere soils, bulk soil, roots and leaves of Brassica pekinensis Rupr.. Rhizosphere soils were collected after 8 weeks of plant growth by first removing the bulk soil from the root system and then by mechanical move off the rhizosphere soil that adhered to the root surface with soft brush. Soil and plant materials were simultaneously extracted with the mixture of methanol and sulfuric acid (100:7, v/v). Seven organic acids, oxalic, malonic, fumaric, succinic, maleic, L-malic and citric acid were identified and quantified by GC equipped with FID. Oxalic, L-malic, and citric acids were found in both the bulk and rhizosphere soils, while most LOAs were not detected in the control treatment. On the contrary, except maleic acid, all other organic acids were detected in the leaves and roots of cabbages treated with nitrate deposition.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.107-118
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• 2000

For the last several decades, the fate of organic pollutants has been extensively studied in natural environments with emphasis on sorption and desorption phenomena. Although the mechanisms involved are not clear yet there is a consensus about the existence of hysteresis in the sorption and desorption of organic pollutants. Furthermore, it is found that hysteresis is the outcome of slow nonequilibrium sorption of organic pollutants, which results in the formation of desorption-resistant fractions of the pollutants. Desorption-resistant fractions may increase as a function of the residence time of the pollutants in the environments. Field monitoring data show a slow but continuous decline of chemicals applied to soil, followed by little or no subsequent disappearance. One plausible explanation for such resistance to biodegradation, desorption, or extraction can be attributed the gradual movement of organic pollutants to less accessible remote sites inside the matrix with time. This phenomenon has been termed sequestration or aging. The fact that some pollutants are sequestered in soil with time may have a great impact on bioremediation and risk assessment, Some portion of the resistant pollutants may still be present in the environments after bioremediation. It requires vigorous means to completely remove the aged portion that may not be further bioavailable. However, precaution should be taken since aging is not always evident. Aging seems to be soil and chemical specific.

• 한국환경과학회지
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• 제6권3호
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• pp.285-291
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• 1997

In order to Investigate the adsorption characteristics of organochlorine pesticides chlorothaloul and dicofol with soul colors and re참tons far souls of an orange orchard, the souls were sampled at 3 re삼tons, respectively. among black volcanic, dark brown volcanic, and broom nonvolcanlc sorts. Every so6 has a higher clay proportion (49-75%) In sol tcuture and the organic carbon content and cation ekchange capacity with soil decreased in the following sequence: Black volcanic > Dark brown volcanic > Brown nonvolcanic sorts. Especially those In black volcauc trolls were much higher than others. The retention time, quantitative detection limit, and extractian , efficiencies of chlorothalonil and dicofol were 2.82min, 1.5ng/mL, 93.6% and 3.64min, 4.5ng/mL. 94 2%, repectlvely. The Freundlich constant, Kd, was higher in dicofol compared to chlorothalonil and In the black volcanic souls that have higher organic carbon content and cation Bkchange capacity. The Freundlich constant, 1 In, was In the range of 0.76-0.89 In the black volcanic sorts that have a higher organic matter(16.4-19.8%), whereas It was In the range of 1.02-1.13 In the brown nonvolcanic souls that have a lower organic matter(2.4-3.4%), and so It was considered that 1 In was dependent on the organic matter.

• 한국환경과학회지
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• 제8권5호
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• pp.587-592
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• 1999

The purpose of this study was to identify the controlling factors to construct tidal flat ecosystems having similar characteristics as natural ones. We transplanted the soil in a constructed tidal flat to a natural one and vice versa. Parameters monitored after these transplantations were silt content, organic matter, bacterial population and oxidation-reduction potential. Moreover, the relationship among silt content, organic matter and bacterial population was investigated by laboratory column experiment. The silt content, organic matter, bacterial population and vertical profile of oxidation-reduction potential in the soil transplanted from the constructed tidal flat to the natural one changed to similar values to those in the natural one. On the contrary, all the parameters for the soil transplanted from the natural tidal flat to the constructed one changed to similar values as those in the constructed one. The silt contents in thses two transplanted solis were in proportion to the organic carbon contents and bacterial population. Similarly, the bacterial population in laboratory column experiment increased with the increase in silt and organic matter contents. It seemed to be important to select a place to enhance accumulative of silt and/or to maintain the silt content by hydrodynamic control of seawater in order to construct a tidal flat having similar characteristics as natural one.