• Journal of Wetlands Research
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• v.16 no.2
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• pp.221-233
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• 2014

Soil erosion, transportation, and sedimentation by water flow often occur in a stream. This excessive occurrence threatens the safety of hydraulic structures, and aggravates natural disasters like flood. To prevent soil disaster according to the soil erosion, it is necessary to predict accurate sediment outflow primarily. Besides, it is very important to choose appropriate models by basin characteristics, to estimate accurate quantity of related factors, and to acquire available hydrological data. Therefore, the purpose of this study is to estimate soil erosion amount and sediment amount according to rainfall-runoff by using rainfall, discharge, and sediment in the Seolmacheon experimental catchment. And, it proposed sediment delivery ratio of the Seolmacheon catchment by result of studying sediment delivery ratio. Hereafter, this study will estimate sediment delivery ratio by basin characteristics, and formulate the method of estimating soil erosion and sediment outflow in various conditions by applying the results in other catchments.

• Asian Journal of Turfgrass Science
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• v.16 no.1
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• pp.11-18
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• 2002

This research was designed to know optimize soil sampling time, soil sampling depth and fertilizers according to season and soil condition in the golf course. One of the results was revealed that sampling point and depth have to be consistent for much fluctuation by sampling. Especially, Soil pH is decreased by soil depth remarkably. Top soil (0-5 cm depth) pH is higher than the sub soils (5-10 cm, 10-15 cm depth). It was confirmed that soil pH would increase when the state of soil is appropriate to H$^{+}$ ion concentration. Therefore, Soil pH modification is always not determined by lime content rather than soil conditions, i.e., Organic matter content, moisture content, and soil air content. More effective fertilizing time according to soil pH correction is the middle of october, and it's quantity is 100 g/$m^2$ silicate and 200 g/$m^2$ lime (Pel-Lime Mini) in this experiment. Recommended soil sampling method for acidity measurement is dividing by soil depth into each 5 cm respectively, rather than mixing 15 cm total soil.

• Journal of Coastal Disaster Prevention
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• v.5 no.4
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• pp.163-172
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• 2018

To propose the design technique and the execution manual of the LWFS(Lightweight Foamed Soil) method using dredged soil, the operation system for the test-bed integrated management, and to establish an amendment for the domestic quantity per unit and specifications, and a strategy for its internationalization. In order to utilize the dredged soil from the coastal area as a construction material, we constructed the embankment with LWFS on soft ground and monitored its behavior. As a result, it can be expected that the use of LWFS as an embankment material on the soft ground can improve the economic efficiency by reducing the depth and period of soil improvement as well as the uses of nearby dredged soil. To verify the utilization of the dredged soil as a material for light-weighted roadbed, soft ground and foundation ground, and surface processing, perform an experimental construction for practical structures and analyze the behavior. It is expected to be able to improve the soft ground with dredged soil and develop technique codes and manuals of the dredged soil reclamation by constructing a test-bed in the same size of the fields, and establish the criteria and manual of effective dredged soil reclamation for practical use. The application technology of the dredged soil reclamation during harbor constructions and dredged soil reclamation constructions can be reflected during the working design stage. By using the materials immediately that occur from the reclamation during harbor and background land developments, the development time will decrease and an increase of economic feasibility will happen. It is expected to be able to apply the improved soil at dredged soil reclamation, harbor and shore protection construction, dredged soil purification projects etc. Future-work for develop the design criteria and guideline for the technology of field application of dredged soil reclamation is that review the proposed test-bed sites, consult with the institutions relevant with the test-bed, establish the space planning of the test-bed, licensing from the institutions relevant with the test-bed, select a test-bed for the dredged soil disposal area.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.3
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• pp.36-51
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• 2011

Global climate change is disturbing the water circulation balance by changing rates of precipitation, recharge and discharge, and evapotranspiration. Groundwater, which occupies a considerable portion of the world's water resources, is related to climate change via surface water such as rivers, lakes, and marshes. In this study, the authors selected a relevant climate change scenario, A1B from the Special Report on Emission Scenario (SRES) which is distributed at Korea Meteorological Administration. By using data on temperature, rainfall, soil, and land use, the groundwater recharge rate for the research area was estimated by periodically and embodied as geographic information system (GIS). In order to calculate the groundwater recharge quantity, Visual HELP3 was used as main model, and the physical properties of weather, temperature, and soil layers were used as main input data. General changes to water circulation due to climate change have already been predicted. In order to systematically solve problems of ground circulation system, it may be urgent to recalculate the groundwater recharge quantity and consequent change under future climate change. The space-time calculation of changes of the groundwater recharge quantity in the study area may serve as a foundation to present additional measures to improve domestic groundwater resource management.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.571-576
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• 2004

In this study, we selected the most effective interpolation method using both the data of sounding the depth of submarine topography and volume-production computer program. After processing the data by volume-production program, and then we selected the most effective interpolation method which nearest actual value of dredged soil quantity. Thus, these interpolation could be used for describing the optimal submarine topography.

• 한국터널공학회:학술대회논문집
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• 2005.04a
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• pp.117-128
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• 2005

This Paper present design parameters of grouting by reviewing several published equations and the results of coupled analysis considering the difference of permeability between soil and grouted zone. Also, the feasibility of couped analysis in the design of grouting is studied for seeping water quantity into tunnel, displacement of tunnel face, drawing down of groud water table, settlement of ground and stress of tunnel supports.

• Journal of Korean Society of Forest Science
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• v.77 no.1
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• pp.109-115
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• 1988

Decrease of the planting area reduced fertilized area of forest. To accomplish the aims of natural regeneration, mini-rotation plantation, diminishing the rotation length, maintaining healthy forest and production of good quality timber, forest fertilization should be continued. In order to improve the deteriorate situation, slow-release fertilizer applied on top soil needs to be developed and aerial application will give diminished cost. Fertilization with tending before tree felling in forest will increase the effect of fertilizer more, Proper quantity of fertilizer by tree species and soil fertility should be found out in the future, Street trees, environmental forest near city and ornamental trees in the residential areas could be also included in this field.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.09a
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• pp.231-234
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• 2001

When constructing subsurface structures and/or wells, the precise estimates of hydraulic parameters must be obtained for operating safety and/or for developing necessary quantity of groundwater. Hydraulic conductivity is mainly subjected to the characteristics of fracture network in the fractured media such as fracture orientation and angle, fracture aperture and frequency, fracture length, interconnectivity of fractures, and filling material, feature of fracture plane. In this study we conducted water injection test at afferent depths on six boreholes drilled in granite of Mt. Geumjeong. hydraulic conductivity was calculated using Moye and Hvorslev methods. The relation between hydraulic conductivity and fracture frequency data obtained from acoustic televiewer and core log were analyzed. The result shows that the correlation between the hydraulic conductivity and the fracture frequency data obtained from acoustic televiewer is better than that with the core log.

• Asian Journal of Turfgrass Science
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• v.5 no.2
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• pp.81-86
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• 1991

The sludge, a waste of brewery industries, was examined for potentials as a natural organic fertilizer (or soil conditioner) for lawn. Trial products were measured for changes of physical, chemical properties in laboratory and seed germination and seedling growth in green house were also tested. The results are as the following:1The sludge from distilled liquor brewery contained high quantity of organic matter which had proper physical and chemical properties for lawn fertilizer (natural organic fertilizer, soil conditioner, top-dressing mix) . It showed good characteristics in handling and capabilities to be developed as commercial products for golf courses. 2.Sludge from beer company needs proper treatment to improve physical properties for futher degradiation. It is because aggregation of the sludge particles prevented microbial activities and changing to soluble form. 3.Green carbon can be used as carbon source for organic fertilizer production using brewery sludge, but it should not contain wood extract which inhibit seed germination and seedling growth.

• Journal of Ecology and Environment
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• v.32 no.4
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• pp.267-275
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• 2009

To investigate the possible applications of plants to remediate heavy-metal-contaminated soil, a pilot experiment was performed for four years in a reclaimed dredging area using two Alnus species, i.e., Alnus firma and Alnus hirsuta. In a comparison of phytomass of the two species at two different planting densities, the phytomass of Alnus planted at low density was twice as high as that of Alnus planted at high density after four years. The Alnus species showed active acclimation to the heavy-metal-contaminated soil in a reclaimed dredging area. A. hirsuta showed greater accumulation of phytomass than A. firma, indicating that it is the better candidate for the phytoremediation of heavy-metal-contaminated soils. In the pilot system, Alnus plants took metals up from the soil in the following order; Pb > Zn > Cu > Cr > As > Cd. Uptake rates of heavy metals per individual phytomass was higher for Alnus spp. planted at low density than those planted at high density in the pilot system. Low plant density resulted in higher heavy metal uptake per plant, but the total heavy metal concentration was not different for plants planted at low and high density, suggesting that the plant density effect might not be important with regard to total uptake by plants. The quantity of leached heavy metals below ground was far in excess of that taken up by plants, indicating that an alternative measurement is required for the removal of heavy metals that have leached into ground water and deeper soil. We conclude that Alnus species are potential candidates for phytoremediation of heavy-metal- contaminated surface soil in a reclaimed dredging area.