• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.5-14
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• 2017

Humic acid was used soil amendment or functional fertilizer in Korean agriculture, and its cation exchangeable capacity was high enough to increase soil buffering from plant toxicant. This study was conducted to evaluate effects of humic acid powder (HA) on composting of livestock manure (LM) and of its application on growth of lettuce. Treatments were designed as follows; livestock manure compost (LM+sawdust+bark+castor meal; Control), control+0.1% HA (0.1% HA), control+0.5% HA (0.5% HA), control+1.0% HA (1.0% HA), control+3.0% HA (3.0% HA), and control+5.0% HA (5.0% HA). The changes of temperature, water content, organic matter content, total nitrogen and ratio of organic matter and nitrogen in HA treatments were similar to those of control. Although pH of 3.0% HA and 5.0% HA blending with HA and LM was lower than those of others, it unaffected by HA blending during composting. Humic acid content of HA treatments was increased by 1.7~4.4 folds than that of control. As compared with odor index, 3.0% HA and 5% HA were decreased than control for composting time. Application of 3.0% HA increased the dry weight of lettuce by about 7% than that of control.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.49-57
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• 2017

The consumption of KimChi, which Korean are a favorite food, has dramatically increased by changes of life style and waste as by-products in KimChi factory. This study was conducted to evaluate an effect of compost of caster oil cake (COC) mixed with waste from KimChi factory (KWF) and its growth effect of lettuce. Treatments were consisted of 4 treatments as COC compost (60% COC+40% sawdust) as control, control+35% KWF (K-1), control+50% KWF (K-2), and control+65% KWF (K-3). Temperature, pH, O.M. and microbial phase of COC composts blended various ratios of KWF or free were unaffected. It was appeared that nitrogen content of KWF treatments was higher, but the ratio of organic matter and nitrogen was lower than the control. Although KWF treatments were acceptable compost under the guideline of Korean, NaCl content of K-3 was 1.91%, and it was very higher than that of others. In comparison with fresh weight and dry weight of lettuce, K-1 and K-3 were similar to control. These results indicated that the waste from KimChi factory was possible to use the composting raw blended materials below 35% mixtures.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.95-103
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• 2004

This study has been assessed the influence of applying sewage sludge to soil amendments on the sorption properties, and leaching potential of three commonly used organophosphorus pesticides, Diazinon, Fenitrothion, and Chlorpyrifos. A sandy soil with a low content of organic carbon was treated with sewage sludge with a ratio sandy soil sludge ratio of 30:1. The sorption was determined with the batch equilibrium technique. The sorption isotherms could be described by Freundlich equation. The Freundlich constant, K value which measures sorption capacity, were 3.97, 9.94, 22.48 for Diazinon, Fenitrothion, Chlorpyrifos in non-amended soil. But in amended soil, K value was 12.58, 28.47, and 61.21 for Diazinon, Fenitrothion, and Chlorpyrifos. The overall effect of sewage sludge addition to soil was to increase pesticides adsorption, due to the high sorption capacity of the organic matter. The effect of sludge on the leaching of pesticides in the soil was studied using packed soil columns. Total recoveries of pesticides in soil and leachate with leaching in soil column, were in the range of about 73∼84%, was reduced with the passage of time. Diazinon moved more rapidly than Chlorpyrifos in the unamended soil due to greater sorption and lower water solubility of Chlorpyrifos. Total amounts of pesticides leached from the sewage sludge amended soils were significantly reduced when compared with unamended soils. This reduction may be mainly due to and increase in sorption in amended soils, as a consequence of the increase in the organic matter content.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.4
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• pp.263-268
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• 2007

This experiment was carried out to evaluate the effects of organic content and to select lodging resistance for six varieties in paddy field of Chungnam province from 2006 to 2007. In this experiment, plant height was increased at the high fertile field and dry matter rate (%) per fresh matter was decreased at the high fertile soil condition but dry matter rate (%) of spike was increased. The dry matter (DM) yield showed higher in Sunwoo barley (13,520kg/ha) and Youngyang barley (12,780kg/ha) at the high fertile field. Fresh yield was also high in Wooho barely (34,720kg/ha) and Youngyang barely (33,670kg/ha) at the high fertile field but yield in high and normal fertile soil condition was not difference. Total digestible nutrients (TDN) content of Youngyang barley and Yuyeon barley was high as 69.5%, 70.3%, respectively, at the high fertile soil condition. According to this result Soman barley and Youngyang barley might be recommendable for whole crop barely in lower organic content condition of paddy rice field and Wooho barley and Soman barley with the lodging resistance and high yield is suitable for paddy field with high organic content.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.433-441
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• 2014

It has been known that sewage containing high-concentration nitrogen affects the efficiency of municipal wastewater treatment plants harmfully. Therefore, research has been actively conducted to treat sewage containing high-concentration nitrogen. The current study has analyzed organic compounds, conducted foaming tests, and operated a laboratory-level nitritation reactor with the subjects of anaerobic digester supernatant and livestock wastewater which are the typical kinds of sewage containing high-concentration nitrogen. According to the results of analyzing organic compounds, soluble inert components form the largest part of anaerobic digester supernatant while particle biodegradable components occupy the most part of livestock wastewater. About the retention time proper for the reaction of nitritation, anaerobic digester supernatant shows 2 days while livestock wastewater indicates 6 days. It seems that the difference in the proper retention time is resulted from the difference of properties in organic compounds and ammonium nitrogen concentration. In addition, livestock wastewater's reactor foam is generated comparatively more than anaerobic digester supernatant's, but it tends to be eliminated faster. It is expected that the findings of this study can be utilized as foundational data afterwards in applying the reaction of nitritation to municipal wastewater treatment plants.

• Korean Journal of Medicinal Crop Science
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• v.11 no.2
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• pp.155-160
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• 2003

This study was carried out to investigate propagation characteristics of seedling and rhizome in Epimedium koreanum NAKAI. Seed germination essentially needed after-ripening duration after harvesting for 250days and more by stratification. At $20^{\circ}C$ seed emergence days and root length were 8 and 0.46cm respectively. The above-ground part of E. koreanum grew until 60days after root cutting and the underground part of it grew after that time. The optimum amount of organic fertilizer was fermented cow-manure with husk 2,000kg/10a that showed $57.5cm^2$ in leaf area per plant, 6.2cm in new rhizome length, and 0.43% in icariin content, an index component of E. koreanum, while inorganic N-fertilizer made E. koreanum worse as it increased. In nutriculture extruded rice hull media was better for growth than perlite media at 1/2 NHRI solution.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.130-135
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• 2002

Water-dispersible colloids are suspected to facilitate transport of contaminants to groundwater. This study evaluated some soil chemical properties in relation to the stability of colloids in soils of Jeju citrus orchards. Thirty surface soil samples were collected, and pH, organic matter content oxalate-extractable Al and Fe contents, and water-dispersible colloid content were measured. In soils of higher pH, water-dispersible colloid contents were higher. The stability of colloids was found to be significantly promoted at pH above 5$\sim$6. Since organic matter can act as a flocculant organic matter content significantly enhanced the colloid stability. In soils of less than 5% organic C, water-dispersible colloid content was expected to be significantly higher. In soils of higher oxalate-extractable Al and Fe contents, colloids remaining in suspension were lower. This indicated that amorphous oxides and hydroxides play important stabilizing roles in soil structure and can stabilize soil clay against dispersion. Therefore in soils of higher pH, lower organic matter, and lower amorphous clay minerals, the stability of water-dispersible colloids and the potential of colloid-mediated transport of organic chemicals to groundwater could be higher.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.130-130
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• 2003

본 연구는 음식물찌꺼기의 재활용 방법의 일환으로 음식물 퇴비와 돈분 퇴비를 혼합, 고추 작물에 적용하여 생육 및 품질면에서 합리적인 시용량을 검증하고 토양 이화학적 특성변화 및 고추 생육과 수량에 미치는 영향을 평가하기 위해 실시하였다. 퇴비의 처리는 관행구(2ton/10a의 돈분 퇴비)와 음식물 퇴비 및 돈분 퇴비의 혼합구인 0.5t:1.5t, 1.0t:1.0t, 1.5t:0.5t, 2.0t:0ton/10a의 4개 처리구등 총 5개 처리구를 난괴법 3반복으로 수행하였다. 돈분 퇴비와 음식물 퇴비의 이화학적 특성을 분석한 결과 음식물 퇴비는 유기물이 기준량에 2배정도 높았으며, NaCl은 공정규격인 1%를 약 2.5배정도 초과하였다. 음식물 퇴비의 시용량 증가에 따라 토양 pH는 처리구별 특별한 변화는 없었으며, EC는 전체적으로 증가하였다. 생육기간 중 대조구와 음식물 퇴비의 처리구간 생육차이가 약간 나타났으며, 그로 인해 고추의 수량에 영향을 미친 것으로 판단된다. 음식물 퇴비 처리구에서 1ton/10a이상 일 때 시용량이 증가할수록 수확량 및 고추 개수에 있어서 감소 경향을 보였지만 수량 차이는 크지 않았다. 또한 capsaicin 함량에서도 음식물 퇴비 처리구간에 큰 차이는 보이지 않았다. 음식물 퇴비의 시용량에 따라 고추에 흡수되는 양분 흡수량은 큰 차이를 보이지 않았다. 결론적으로 음식물 퇴비를 시용한 고추 재배 시험에서 토양의 유기물 함량 증가, 물리성 개량, 토양 pH 완충력 증대 등의 효과를 보였다. 그러나 음식물 퇴비를 50%이상 돈분 퇴비와 혼합 시용시 고추의 수량이나 품질의 저하 및 토양의 염류집적의 우려가 나타났으나, 50%이하로 혼합 시용시 큰 무리는 없었다. 현재 적정 혼합비율을 구명하기 위한 연구가 진행중이다.

• Korean Journal of Plant Resources
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• v.23 no.2
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• pp.179-186
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• 2010

This study was conducted to provide basic information for conservation and restoration through investigation of vegetation and soil condition of Megaleranthis saniculifolia Ohwi, Korean endemic species, in Mt. Halla, Jeju Island. Very few individuals were discontinuously distributed and restricted at 1,075 m above sea level, very steep slope ($60-70^{\circ}C$), rocky area of north face of Eorimok Valley. For investigation of environmental condition, we established two $10\;{\times}\;10\;m$ quadrats in the habitats and one control quadrat. Twenty-four species were found at site 1 under 10-12 m Carpinus laxiflora tree layer (35%) and soil conditions are pH 5.9, moisture content (field capacity) 9.39%, organic carbon 8.22% and organic matter 14.17%, respectively. Site2, 15 taxa were found under 8-12 m Platycarya strobilacea tree layer (40%) and soil conditions are pH 5.07, moisture content 4.99%, organic carbon 5.34% and 9.21 percentage of organic matter. In the control quadrat, 14 taxa were found under 10 m Carpinus laxiflora tree layer (10%) and soil conditions are pH 5.27, moisture content 6.23%, organic carbon 4.74% and organic matter 8.17%, respectively. The principal causes of threat which were investigated in this study are competition among company, very steep slopes, artificial management of valley. For restoration and conservation of habitats, it is needed to suitable plans.

• Journal of Marine Life Science
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• v.5 no.1
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• pp.25-33
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• 2020

The Asan Bay, which has semi-diurnal tide with macro-tidal range, is affected by both freshwater discharge from the sluice gates in the sea dikes and tidal seawater inputs from the Yellow sea. Understanding water quality change in response to tides is important since tides can impact the short-term variations in physical and chemical water properties as well as the response of biological properties. The diel variations in water quality were seasonally investigated at 2 hour intervals from a fixed station in the Asan Bay. In the results, water temperature and salinity consistently fluctuated in phase or out of phase with tidal height. Especially salinity was positively correlated with tidal height. The concentrations of total suspended solids were higher in the bottom water than in the surface and fluctuated greatly over the tidal cycle recording higher values at low tide than at high tide. Nitrite+nitrate levels also fluctuated out of phase with tidal height and correlated negatively with tidal height. Other nutrients also showed a similar pattern. The pattern was distinct in July when freshwater was discharged before the field sampling. The concentrations of organic materials, total nitrogen and total phosphorus greatly fluctuated over the tidal cycle and were generally out of phase with tidal height. Most materials except particulate organic forms were correlated with salinity indicating that freshwater inputs were sources for the materials similarly to the dissolved inorganic nutrients. The results suggest that water quality (except dissolved oxygen and pH) and nutrients including organic materials was largely affected by tides in the Asan Bay.