• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.503-519
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• 2014

This study was conducted to investigate ginger growth and its nutrient uptake depending on changes of soil properties as affected by applications of green manure crop and/or charcoal in continuous cropping system. The green manure crops applied were barley and hairy vetch, and charcoal was additionally treated in selected plots as a soil conditioner. Experimental plots were prepared as Plot 1 (control), Plot 2 (barley of 8kg $10a^{-1}$), Plot 3 (hairy vetch of 12kg $10a^{-1}$), Plot 4 (charcoal of 1,000kg $10a^{-1}$ and barley 8kg $10a^{-1}$), and Plot 5 (charcoal of 1,000kg $10a^{-1}$ and hairy vetch of 12kg $10a^{-1}$) with two different soil conditions (high clay content, HCC and low clay content, LCC). When comparing selected chemical properties of soils before and after cultivating ginger plant, soil pH decreased from 6.9~8.1 to 6.8~7.6, and electrical conductivity (EC) also declined from $0.45{\sim}1.25dSm^{-1}$ to $0.30{\sim}0.61dSm^{-1}$. However, the content of soil organic matter (SOM) and total nitrogen (T-N) increased. Thus, the soil chemical properties were improved with the applications of green manures and charcoal. Also, macro- and micro-nutrient contents of ginger plants in the different plots were various between normal and diseased plants grown in soils with HCC and LCC. In particular, the concentration of manganese (Mn) was 3~4 folds higher in the diseased plant than in the normal plants. Ginger growth status and yield was relatively improved with the applications of green manures and charcoal as comparing with control plot. Especially in the Plot 4 with LCC, the ginger plant was not infected by root-rot disease.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.13-23
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• 2008

The triaxial compression tests and consolidation tests using NaCl solution and leachates as substitute pore (or saturated) water in samples were carried out to find out the behavior characteristics of strength, deformation and permeability coefficient of contaminated clay. Also, the chemical property analysis on the clay samples using scanning electron microscope and energy dispersive x-ray spectrometer were involved. The magnitudes of composition ratio were shown in the order of O, C, Si, Al, and Fe as a result of chemical composition analysis for clay samples. Besides, as the results of triaxial compression tests and consolidation tests, the shear strength, compression and permeability properties were increased with increasing in the concentration of contaminant (NaCl). It may be considered that these circumstances be caused by the changes of soil structure to flocculent structure due to the decrease in the thickness of diffuse double layer with increasing in the concentration of electrolyte. MT3D model was also using to grasp the procedures that the groundwater may be contaminated by the leachates permeated through the clay liner. The results of contaminant transport analysis showed a tendency that the predicted concentration of groundwater was higher with increasing in the initial concentration of $Cl^-$ ion and increased as a nonlinear curves with time. The transportation distance calculated by the use of regression equation between the distance from contaminant source and the concentration of $Cl^-$ ion was increased with increasing the initial concentration.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.247-257
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• 2018

This study was conducted to find out the optimum silicate fertilization for improving the quality and density of zoysiagrass (Zoysia japonica Steud.), the growth of zoysiagrass and changes in chemical properties of soil in field experiments treated with different levels of silicate fertilizer during 3 years from 2012 to 2014. An increase in the silicate fertilizer from 100, 200, to $400kg\;10a^{-1}$ led to a significant increase in the fresh and dry weight of shoots and stolons, the number of shoots and length of stolon, but were not significantly different between 200 and $400kg\;10a^{-1}$. Moreover, soil pH, EC and the contents of available $SiO_2$ were increased as the rate of silicate fertilizer application increased. Thus, these results demonstrated that the silicate fertilizer rate for maximum growth of zoysiagrass was $200kg\;10a^{-1}$ in consideration of improving growth of zoysiagrass and the chemical property of the soil.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.44-63
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• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.

• Korean Journal of Organic Agriculture
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• v.10 no.1
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• pp.87-97
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• 2002

This study was conducted to investigate the effect of microbial fermentation compost on the growth, yields and components of Altari Radish, and the soil physicochemistry property by cultivating area. microbial fermentation compost, 90kg/10a, 180kg/10a, 270kg/10a, chemical fertilizer plot were used. The results were summarized as follows ; Change of soil microbial after application microbial fermentation compost, The number of bacteria and actinomycetes in developed land showed the increased tendency. The application effects of microbial fermentation compost on the growth and yield of Altari radish were increased by excessive application with all kinds of microbial fermentation compost, especially, treatment plot at 270kg/10a was the highest. Change of components in Altari Radish was not different between treatments.

• Journal of Soil and Groundwater Environment
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• v.8 no.1
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• pp.57-67
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• 2003

Nitrate contamination by human activities is a serious problem to water-supply in agricultural area. Shallow groundwater is the main source of water-supply, but it is very sensitive to contamination. Study area for nitrate contamination is a region of Iljuk, Kyunggi where is an agricultural area having many livestock facilities in various scales. As a result, the points having availability of incoming of external contaminant are 77%, and the ones over the Drinking Water Limit (DWL) are 32～42%. For a nitrogen isotope analysis, all the points having availability of incoming of external contaminant have $\delta$$^{15}$ N-NO$_3$ values over 5$\textperthousand$, and the points of 59% are strongly affected by nitrogen originated from animal wastes. The major source of nitrate in this area is intensive livestock facilities. Even though a livestock facility had enclosed, it affects groundwater quality for a long time. The chemical property of contaminant source is various according to animal species in surface water, but not in groundwater since some solutes are removed by reactions during an inflow to subsurface.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.157-160
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• 2011

This study was conducted to find a method using the application of rice bran and mixed expeller cake at machine transplanting rice paddy field. Different ratios of rice bran and mixed expeller cake were sprayed as substitute of chemical fertilizer (nitrogen 90kg $ha^{-1}$) before transplanting. Nitrogen content was highest in 30th day after transplantation, and in relation to treatments the order was the following: Rice bran 1,000kg $ha^{-1}$ + Mixed expeller cake 1,374kg $ha^{-1}$ > rice bran 2,000kg $ha^{-1}$ + Mixed expeller cake 948kg $ha^{-1}$ > rice bran 3,000kg $ha^{-1}$ + Mixed expeller cake 522kg $ha^{-1}$. Number of panicle and spikelets per $m^{-2}$ was higher in rice bran 1,000kg $ha^{-1}$ + Mixed expeller cake 1,374kg $ha^{-1}$ and rice bran 2,000kg $ha^{-1}$ + Mixed expeller cake 948kg $ha^{-1}$ than in rice bran 3,000kg $ha^{-1}$ + Mixed expeller cake 522kg $ha^{-1}$ and the yields was the highest in rice bran 1,000kg $ha^{-1}$ + Mixed expeller cake 1,374kg $ha^{-1}$.

• Korean Journal of Medicinal Crop Science
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• v.22 no.4
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• pp.301-305
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• 2014

This study was carried out to investigate the vegetation and habitat environment of Sageretia thea which is distributed in Jeju island, Korea. Sageretia thea were mainly distributed to the west area in Jeju island. Soil pH and EC of Sageretia thea habitat were 5.8 and $0.34dS{\cdot}m^{-1}$. The contents of organic matter, available phosphate, exchangeable potassium, exchangeable sodium, exchangeable magnesium and exchangeable calcium were 15.27%, $13.6mgkg^{-1}$, $0.27cmol_+kg^{-1}$, $1.3cmol_+kg^{-1}$, $1.7cmol_+kg^{-1}$, $4.9cmol_+kg^{-1}$, respectively. Thirty one taxa including 25 families, 31 genus, 27 species and 4 varieties were identified surrounding Sageretia thea habitat. Specific plant species were 1 taxon in III grade, 1 taxon in I grade and 3 taxa in I grade.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.3
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• pp.115-122
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• 2001

The purpose of this study was to suggest the possibility of utilizing the wildflower pasture as the livestock herbage sources as well as promoting the public interests. Not only dry matter (DM) yield and soil properties of pastures were observed, but also chemical composition of herbages was analyzed. The experimental design includes four treatments: Conventional pasture(COP, forage 6 species), Bottomgrass pasture(BOP, turf grass 6 species), Native wildflower pasture(NWP, turf grass 6 species + native wildflower 11 species) and Introduced wildflower pasture(IWP, turf grass 6 species + introduced wildflower 9 species). The field trials were carried out on the experimental pasture plots at Chungnam National University throughout from 1997 to 2000. The results obtained are as follows : 1. As wildflower pasture was composed of turf grasses and wildflowers, the yearly mean of DM yield in the wildflower pastures (NWP 6,688kg/ha and IWP 7,240kg/ha) was lower than that of COP(8,592kg/ha) or BOP(7,264kg/ha)(p<0.05). This result indicated that the forage productivity of wildflower pasture for livestock is low. 2. The nutritive quality of herbages from wildflower pasture tended to be slightly low compared to that of COP and BOP. On the other hand, compared with IWP, the content of CP, NDF and lignin of herbages from NWP were lower than those from IWP, while IVDMD was higher(p<0.05). 3. The pH and the content of exchangeable Ca in NWP and IWP soils were tended to be low compared to those of COP in changes of soil properties after 3-years experimental trials, while the contents of organic matter, nitrogen, available phosphate, Mg and K were slightly improved. In conclusion, even though DM yield seem to be lower in wildflower pasture than those of COP, and the nutritive quality of herbages from wildflower pasture tended to be slightly low compared to that of COP and BOP. but, possibility of utilizing herbages from wildflower pasture for livestock was to some extent expected. In addition. compared to COP, wildflower pastures improved the property of soil. Thus, although wildflower pasture was not enough for livestock as a herbage, wildflower pasture has enough possibility for promoting the public interest.

• Journal of the Korean Geotechnical Society
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• v.36 no.12
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• pp.57-68
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• 2020

In the case of two-dimensional analysis generally applied in the analysis of Earth Retaining Wall, mutual interference occurs due to earth pressure, when the excavation width is small, and in the section where the excavation width is small, and the resulting influence makes it difficult to secure reliability in the horizontal displacement of the retaining wall when performing 2-dimensional analysis in a section with a small excavation width. This study performed two-dimensional and three-dimensional finite element analyses on excavation depth (H) and excavation width (B) under various conditions for the H-pile earth wall, in the geological conditions of clayey soil, sandy soil, and weathered rock, and examined the relationship between excavation width and horizontal displacement according to each condition, to identify the boundary of the excavation width, which is the range of mutual interference caused by earth pressure. As a result, it was possible to clearly distinguish the analytical boundary according to the excavation width only in the clayey soils with relatively large horizontal displacement. It is concluded that it is reasonable to perform a 3D finite element analysis, which is similar to the actual behavior, if the excavation scale (B/H) is 2.0 or less, with the digging width less than 12 m at a digging depth of 10 m or less, and with the the one less than 24 m at a digging depth of 10 m or more, and that 2-dimensional finite element analysis may be used in cases where the excavation width is greater than 12 m when the excavation scale (B/H) is 2.0 or more and the excavation depth is 10 m or less, and the excavation width is greater than 24 m at an excavation depth of 10 m or more.