• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1623-1623
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• 2001

Composting is a biological method used to transform the organic waste into stable, humified organic amendments. Humification is indicated as the key factor in improving the quality of compost, because of the importance of humic substances to soil ecology, fertility and structure, and their beneficial effects on plant growth The compost constituents vary widely, however, the degree of maturity is very important factor in compost quality. So this experiment carried out to determine the rapid estimation of the quality in cattle, pig, chicken and waste composts using near infrared reflectance spectroscopy(NIRS). Near infrared reflectance spectra of composts was obtained by Infra Alyzer 500 scanning spectrophotometer at 2-nm intervals from 1100 to 2500nm. Multiple linear regression(MLR) or partial least square regression (PLSR) was used to evaluate a NIRS method for the rapid and nondestructive determination of humic acid contents in composts. The results summarized that NIR spectroscopy can be used as a routine testing method to determine quantitatively the humic acid content in the compost samples ondestructively. Especially, we supposed that absorbance around 2300nm is related to humic acid as a factor of compost maturity. However the NIR absorption approach is empirical, it actually requires many combinations of samples and data manipulations to obtain optimal prediction.

• Korean Journal of Environmental Agriculture
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• v.25 no.3
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• pp.262-267
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• 2006

Increased application of glyphosate (Gly) in glyphosate-resistant (GR) soybean cropping systems may affect rhizospheric microorganisms including IAA-producing rhizobacteria (IPR) and their effect on the growth of soybean. This field experiment was conducted to assess IPR populations in the rhizosphere of GR soybean ('Roundup-Ready' DeKalb DKB38-52) treated with glyphosate and foliar amendment treatments such as $PT21^{(R)}$ (urea solution with N 21 %) and $Grozyme^{(R)}$ (Biostimulant: mixtures of micro nutrients and enzymes). Effects of herbicide, sampling date, and their interaction on total bacterial numbers were significant (P < 0.001, 0.001, 0.013, respectively). Total bacteria (TB) numbers were increased with glyphosate treatment at 20 d after application and highest TB populations were associated with $Grozyme^{(R)}$ application, possibly due to the additional substrate from this product. The IPR of the soybean rhizosphere was significantly affected by herbicide, sampling date, and the herbicide*foliar amendment interaction. The ratios of numbers of IPR to TB ranged from 0.79 to 0.99 across the sampling dates irrespective of treatments. IPR numbers were slightly hindered by glyphosate application regardless of foliar amendment.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.894-898
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• 2012

본 연구는 밭에서 발생하는 비점오염물질을 저감하기 위하여 기존의 볏짚거적을 이용한 저감방법에 PAM과 Gypsum을 처리하였을 때, 표면유출량과 기저유출량, 유사량 그리고 탁도 등에 미치는 영향을 모의하고자 하였다. 연구 방법은 인공강우 시험기와 토양상자를 이용한 실내실험을 통하여 지표피복재의 종류와 강우강도 그리고 경사도에 따른 직접유출량과 유사량을 측정하고 비교하였다. 경사도 (10 %, 20 %)와 강우강도 (30 mm/hr) 그리고 지표피복재의 종류에 따라 실험처리를 하였으며, 지표피복재는 볏짚(Rice straw mat)+PAM (Polyacrylamide)+Gypsum, 볏짚+PAM+톱밥 (Sawdust)+Gypsum, 볏짚+PAM+왕겨 (Chaff)+Gypsum으로 구분하여 제작하였다. 실험 결과 볏짚을 이용한 다양한 피복소재를 이용해 지표를 피복할 경우, 대조구(나지)에 대비 유출수량, 토양유실 그리고 탁도 저감에 큰 효과가 있는 것으로 나타났다. 지표를 피복한 처리구의 평균 표면 유출수량은 대조구와 비교할 때 72~85.6 %가 저감되었다. 그러나 동일조건의 Gypsum을 첨가하지 않은 연구와 비교 시 Gypsum의 혼용으로 인한 효과는 크지 않은 것으로 나타났다. 세분화된 강우강도와 경사도 조건에 따른 실험이 필요하지만 본 연구의 결과에 기초할 때, 지표의 피복과 토양개량제를 첨가하는 방법은 강우 시 발생하는 표면유출수와 유사 그리고 탁수를 저감시킬 수 있는 최적영농관리방법 (Best management practice)의 하나로 판단된다.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.2
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• pp.71-76
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• 1976

Field experiments were conducted to study the effect of amendments such as lime and organic matter for mulberry trees on the newly reclaimed sandy loam soil for three years. The results are summarized as follows. 1. Compared to the N.P.K check plot with treatments, leaf yield was increased by 20 to 80%. Leaf yield was higher in the order of NPK+magnesia lime < NPK+compost > NK+fused phosphate NPK+green manure > NPK+barley straw> NPKplot. 2. Mulberry leaf yield showed high significant positive correlation with total weight and volume of root, length and number of wattles and the content of CaO or MgO in leaf respectively. 3. It is known that dead part sympom of top branch during cold season is associated with unbalance magnesium to potassium in mulberry leaf. It is estimated that such symptom was deminished when the ratio of $K_2O/MgO$ in leaf becomes 6.0 or higher. 4. In establishing a mulberry field on hilly reclaimed soil, application of magnesium and calcium with compost was essential but higher amount of potassium fertilizer should be followed in order to prevent dead part symptom of top branch of mulberry trees.

• Applied Biological Chemistry
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• v.24 no.1
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• pp.1-6
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• 1981

Studios on the effects of rice straw amendments, soil autoclaving and repeated application related to disappearance of diazinon (diethyl 2-isopropyl -4-methyl -6-pyrimidinyl phosphorothionate) in submerged soils and paddy water were conducted under the laboratory conditions. Degradation of diazinon was slightly accelerated by the amendment of rice straw. The amended soil had 2.4 days shorter half life for diazinon than unamended soil. By autoclaving soils, diazinon degradation was greatly inhibited. The autoclaved soil had about 20 days longer half life for diazinon than the non-autoclaved soil. After repeated application of diazinon granules to the submerged soils, rapid degradation of the insecticide occured in flooded soils and paddy water. The development of diazinon degrading factors in flooded soils and paddy water after repeated application was roughly proportional to the increase of the frequency of diazinon application. By autoclaving soils and paddy water which received repeated application of diazinon, no rapid biodegradation of the insecticide occurred during the 30 days incubation period.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1799-1808
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• 2000

To investigate the applicability of loess as a coagulant. the optimum conditions of coagulation and efficiency comparison of several coagulants (PAC, PACS, LAS) in chemical treatment of livestock wastewater were performed. As a result, the optimum mixing ratio of loess and lime(CaO) was 3:7. The optimum dosage of the mixed coagulant was 30 g/L. The optimum speed for rapid mixing of the mixed coagulant was 200 rpm at 1 min. and the optimum speed for slow mixing was 50 rpm at 10 min. The mixed coagulant showed the removal efficiency of turbidity, SS, BOD, $COD_{cr}$. T-P and TKN to 95.8%, 92.5%, 71.6%, 71.1%, 98.2% and 32.5%, respectively, which was better than other several coagulants. The mixed coagulant was possible to use as substitutional coagulants of traditional coagulant, and the producted sludge can use as a soil amendments.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.4
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• pp.64-73
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• 1999

This study was conducted to find out the effects of hydroseeding material and seed mixture on the revegetation of rock cut-slopes by PEC4 (Polymer-Ecology-Control) Hydroseeding Measures. PEC4 hydroseeding material was applied to four cut-slopes using hydroseeding measures from April to August, 1999, and the field survey was carried out by monthly. PEC4 material consisted of bark compost and organic soil amendments. This material has high content of organic matter and high level of water holding capacity. PEC4 hydroseeding material shows low level of soil hardness, so it gives to good condition for seed germinating and plant growing in early stage. PEC4 material attached at rock cut-slopes by two types of adhesive agent was not eroded by rainfall. The plant coverage and number of plant species were affected by mixing ratio of seeds and seeding timing. From the viewpoint of plant establishment, the optimal hydroseeding timing of mixed seeds for plant growth seems to be in May. Most of the plant seeds were germinated well and they covered rock cut-slopes so quickly and effectively. Plant importance value of Silene armeria and Platycodon grandiflorum. were higher than any other seeded-native species in the competition between native species and exotic species, so they have enough possibility to be used for slope revegetation works. Thus it leads to conclusion that the revegetation method used in this experiment was a very effective method for plant establishment on rock cut-slopes.

• Microbiology and Biotechnology Letters
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• v.48 no.2
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• pp.99-112
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• 2020

Rhizoremediation, based on the ecological synergism between plant and rhizosphere microorganisms, is an environmentally friendly method for the remediation of petroleum hydrocarbon-contaminated soils. In order to mitigate global climate change, it is necessary to minimize greenhouse gas emissions while cleaning-up contaminated soils. In rhizoremediation, the main factors affecting pollutant remediation efficiency and greenhouse gas emissions include not only pollutant and soil physicochemical properties, but also plant-microbe interactions, microbial activity, and addition of amendments. This review summarizes the development in rhizoremediation technology for purifying oil-contaminated soils. In addition, the key parameters and strategies required for rhizoremediation to mitigate climate change mediation are discussed.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.610-613
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• 2012

Oyster shell has a high content of $CaCO_3$ to be used as a acidic soil amendment. To enhance productivity of barley and soil microbe in an upland soil, oyster shell and calcium-magnesium carbonate were selected as a soil amendments in this study. A field experiment was treated no treatment (hereafter, control), oyster shell lime $3.09Mg\;ha^{-1}$ and $2.38Mg\;ha^{-1}$, and calcium-magnesium carbonate $2.38Mg\;ha^{-1}$ as amount of lime requirement in silt loam soil. The yield of barley from the oyster shell lime treatment was the highest. The protein content of barley was the highest of 11.1% in the calcium-magnesium carbonate, followed by 10.7% for the control, 10.6% for the oyster shell lime $3.09Mg\;ha^{-1}$, and 10.4% for the oyster shell lime $2.38Mg\;ha^{-1}$. Soil pH value was higher than that of control in harvesting stage. In addition, the population of soil bacteria was highest in oyster shell lime $2.38Mg\;ha^{-1}$, actinomycetes was highest in calcium-magnesium $2.38Mg\;ha^{-1}$. We concluded that the oyster shell lime can be effective to restore soil nutrient and microbe balance in an upland soil.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.858-863
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• 2010

The blueberry farming requires the soil condition of well-drainage, pH of 4.5 to 5.2, and high in organic matters for stable growth and development. Most of soil type of cultivated land in Korea, however, belongs to alkaline soils with low organic matter content and poor drainage. Therefore, the blueberry farmers use peat moss heavily to improve the soil condition, but the guideline on the effective and economic ratio of peat moss is not established yet. This study was performed to determine the cost effective peat moss ratio for amending soils, and to investigate the feasibility of using sawdust and coco peat as soil amendments. Peat moss, coco peat and sawdust are mixed with soil at the ratio of 0, 12.5, 50 and 100% (v/v). Among 3 organic materials with various mixture ratios, the pH of soil was the lowest in 100% peat moss and sawdust mixtures (pH 3.67 and pH 3.73, respectively), followed by pH 5.30 at 50% peat moss. The soil organic matter content are directly proportional to the mixture ratios in all three organic materials and the same trend was observed in the variation of content of exchangeable potassium in the coco peat treatments. On the contrary, the content of available phosphate, exchangeable calcium and magnesium decreased with increasing the ratio of organic materials. The nitrogen content in the leaves decreased as increasing the ratio of peat moss and coco peat in soil, but not of sawdust. The content of phosphate decreased but potassium increased as the ratio of sawdust and coco peat increased. There was no clear difference in the contents of magnesium and calcium among 3 organic materials. The plant height, stem diameter and dry weight of blueberry plants were the highest in 50 % peat moss, followed by 12.5% peat moss and 12.5% coco peat. The plants in 100% peat moss showed very poor growth. It can be concluded that peatmoss, when applied and managed appropriately, will be a good material for improving soil condition as well as securing desirable growth for blueberry. Upon coupling economic aspect, the optimum mixing ratio of peatmoss for blueberry farming is approximately 25-50%.