• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.1
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• pp.20-28
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• 1999

Nine soil media when placed over a plastic sheet with three seeding rates were evaluated for influence on covering rate, height, growth, surface hardness, tear strength and sod establishment of Kentucky bluegrass. 1. Bark, peat and vermiculite over a plastic sheet had good effect in terms of the establishment of Kentucky bluegrass sod. 2. The good establishment of Kentucky bluegrass sod grown on bark, peat and vermiculite over a plastic sheet seemed to be caused by physical and chemical properties of each soil medium. 3. Sand, sandy loam, perlite and peatmoss caused poor effects on the covering rate, the growth, and the tear strength of Kentucky bluegrass. 4. Optimum seeding rate was $10g/m^2$ in terms of density and competition. 5. Good quality sod more depended on soil media than on seeding rates in this study.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.4
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• pp.252-258
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• 2018

A larger energy consumption and concentration of population induced green house gas glowing and heat island effect in the urban space. Roof green system was a effect method to reduce green house gas and heat concentration in the city. Therefore, construction of this system was increasing. Most of lightweight soil used in roof green system was perlite, but this caused dust and skin disease. So it needed to develop another new lightweight soli for roof green system. Meanwhile, a thermoelectric power plant generated bottom ash as a by-product. According to previous research, bottom ash could be used for artificial lightweight soil with 60 wt% of mixing rate. But this study was proceed to develop a artificial lightweight soil using bottom ash with higher mixing rate by 65 wt% and different organic ingredients. First, physical and chemical properties of bottom ash was investigated. Then test according to landscaping design standard was proceeded for various artificial lightweight soil mix types using bottom ash, bark, compost and coco peat. As a result, the artificial lightweight soil with 65% of bottom ash, 30% of bark and 5% of compost was suitable for low and middle range of soil standard.

• Journal of Soil and Groundwater Environment
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• v.17 no.4
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• pp.36-43
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• 2012

Various methods are used to remediate soil contaminated with heavy metals or petroleum. In recent years, harsh physical and chemical remediation methods are being used to increase remediation efficiency, however, such processes could affect soil properties and degrade the ecological functions of the soil. Effects of soil washing, thermal desorption, and land farming, which are the most frequently used remediation methods, on the physicochemical properties of remediated soil were investigated in this study. For soils smaller than 2 mm, the soil texture were changed from sandy clay loam to sandy loam because of the decrease in the clay content after soil washing, and from loamy sand to sandy loam because of the decrease in the sand content and increase in silt content during thermal desorption, however, the soil texture remained unchanged after land farming process. The water-holding capacity, organic matter content, and total nitrogen concentration of the tested soil decreased after soil washing. A change in soil color and an increase in the available phosphate concentration were observed after thermal desorption. Exchangeable cations, total nitrogen, and available phosphate concentration were found to decrease after land farming; these components were probably used by microorganisms during as well as after the land farming process because microbial processes remain active even after land farming. A study of these changes can provide information useful for the reuse of remediated soil. However, it is insufficient to assess only soil physicochemical properties from the viewpoint of the reuse of remediated soil. Potential risks and ecological functions of remediated soil should also be considered to realize sustainable soil use.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.705-711
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• 2007

We should treat carefully the one related to human rights among a large number of decision-making in our daily lives. As it is necessary to obtain physical evidences in the process of criminal investigation for solving a certain crime based on the principle of evidence, it leads to an increase in demand for forensic science and forensic geology. Forensic geology could be regarded as a fusion discipline of geology and forensic investigation and it is principally concerned to the study on the connection of a suspect and a crime scene with soil evidence which could be experimented using geological data and methods. So these results could be used as valuable information in a court. After its academic foundation has been builded since the last 1970s, its research objects have been expanded from soil evidence like rocks, minerals, soils, sediments to sociocultural, political, military and medical objects like ancient relics, mines, corpses. Its role is expanded from the simple finding of a particular location to the examination of archaeological theories and historical facts, the testimony of the cause of environmental pollution and the chronic demonstration of geological distribution of plants and anthropological origination. And these bring this discipline promptly to accept developed geological methodologies and to satisfy various forensic geological needs. Specialized forensic investigation institutes work actively for the R&D activities of forensic geology. In Korea, national institute of scientific investigation works a small part of forensic geological activities in total activities of forensic investigation. In conclusion, we concern to the importance of systematic discussion of building in proper position of forensic geology through its R&D methods, application cases of its performance and etc. based on geological characteristics in our country by a specialized geoscience institute.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.132-136
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• 2007

최근 지구온난화로 인한 이상기후의 영향으로 강우일수는 줄고 있으나 강수량은 예년과 비슷한 수준을 보이고 있다. 이로 인해 갈수기의 용수부족 현상은 더욱 심해지고. 장마철의 홍수피해와 게릴라성 집중호우로 인한 피해가 커지는 등 해가 갈수록 홍수 예경보의 중요성은 더욱 높아지고 있다. 그럼에도 불구하고 현재 홍수 예경보 체계는 몇 가지 문제를 가지고 있다. 기존 예경보 체계의 경우 한 번의 예측을 수행하기 위해 수반되는 전처리과정과 주계산과정을 거치는 동안 각 과정에서 발생한 오차들이 반복, 누적되어 최종 결과물(예측된 유출량) 속에 모두 포함된다. 또한 기존 체계에서는 유출모형을 적용하기 위해서 토양형. 피복상태 등에 관련된 매개변수들이 필요한데. 이러한 매개변수의 결정에 어려움이 있고. 불확실성을 갖고 있다. 본 연구에서는 불확실성을 적극적으로 인정하고 수학적으로 해석하려는 fuzzy 이론을 신경망 이론에 도입하여 홍수 예경보 시스템의 운영과정에서 발생하는 불확실성의 문제를 해결하고자 하였다. 본 연구에서 사용한 ANFIS(Adaptive Neuro-Fuzzy Inference System)은 data driven model(자료에 기반을 둔 모형)의 하나로 다음과 같은 장점을 가진다. 우선 data driven model은 유역의 물리적, 지형적 특성을 고려하지 않고(매개변수설정에서 발생하는 문제 해결 가능), 입력자료와 출력자료만을 고려하여 구축되는 모형이므로, 유역의 물리적 자료나 지형 자료와 같은 방대한 양의 자료 수집이 필요 없고, 일단 모형이 구축되면 자료의 입력만으로도 신뢰성 높은 결과를 단시간 내에 효율적으로 획득할 수 있다. 그리고 유역 내의 상황이 변화하더라도, 이들의 영향을 고려하여 쉽게 모형을 갱신할 수 있다. 마지막으로 모형의 구축 과정이 물리적 모형에 비해 비교적 간편하다는 장점이 있다. 본 연구에서는 ANFIS를 통해 탄천유역의 강수량 자료와 대곡교의 수위자료를 입력자료로 사용하여 대곡교의 수위를 예측하였다. 입력 자료는 시간차 계열의 강우량과 수위 자료를 사용하였으며 모형을 통하여 t+1, t+2, t+3 시간 후의 수위를 예측하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.603-603
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• 2015

모든 외재적 형식의 가뭄을 모니터링하고 예측 및 평가하기 위해서는 가뭄지수가 필수적 요소로써 이용된다. 일반적으로 가뭄지수는 단일지수(single index), 다중지수(multiple index), 복합지수(composite index)로 분류되며 대부분 강수량, 유출량, 토양 수분량 등과 같은 하나의 변수만을 사용하는 단일지수이다. 가뭄지수는 가뭄평가에 있어서 각각의 장단점이 있다. 하나의 변수를 사용하는 가뭄지수는 계산이 간편하지만 가뭄의 물리적 특성을 정확하게 반영할 수 없기 때문에 신뢰할 수 있는 가뭄평가에 충분하지 않다. CDI(Composite Drought Index)는 PDSI(Palmer Drought Index), ADI(Aggregate Drought Index), SWSI(Surface Water Supply Index)와 같은 다중지수의 개념을 착안하여 고안되었으며, 모든 가뭄 형태(농업적 수문학적 기상학적)와 관련된 강우량, 유출량, 정규식생지수(NDVI)를 변수로써 사용하였다. NDVI는 MODIS(Moderate resolution imaging spectroradiometer)에서 제공하는 16일 간격의 위성자료를 이용하여 계산되었고 이와 시간 스케일을 맞추기 위해 나머지 두 변수 또한 16일 시계열을 사용하였다. CDI는 (1)각 변수들의 시계열을 행렬로 나타내고 (2)이것을 정규화하여 무차원 행렬로 변환한 후 (3)연구 지역의 최고습윤상태(most wet condition) 및 최고건조상태(most dry condition)의 차이값을 기반으로 하여 산정된다. 본 연구에서는 상대적으로 다른 유역에 비해 장기적이고 연속적인 자료를 확보할 수 있으며 농경지와 산림지역 비율이 높은 낙동강 유역을 대상유역으로 설정하였으며, 2001-2013년 기간의 자료를 이용하였다. 그 결과 연구 기간 중 실제 발생했던 가뭄을 반영하는 것을 확인하였다. 또한 CDI는 다양한 변수의 활용으로 가뭄의 물리적 특성의 반영이 가능하며 연구 지역의 기상 조건에 직접적으로 관련된 결과를 나타낸다. 자료의 가용성에 따라 적용범위가 제한적일 수 있으나 입력값으로 사용된 변수와 시계열을 편의와 효율에 따라 유연하게 적용할 수 있다. 따라서 CDI는 농업적, 수문학적, 기상학적 가뭄의 모든 관점을 통합하는 실용적 가뭄지수로써 사용될 수 있는 가능성을 포함하고 있다.

• Asian Journal of Turfgrass Science
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• v.18 no.3
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• pp.149-163
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• 2004

Physical and chemical properties of root zone mixes and methods of green construction are important considerations for improving turf grass quality for putting greens. This study compared Penncross creeping bentgrass (Agrostis palustris Huds.) performance as affected by three root zone construction systems with three amendments (sand, peat, and zeolite). The objective of this study was to determine if an amended California construction system would improve green performance during establishment (1998-1999) and maturation (2000-2001). Three treatments were tested: California ($100\%$ sand), USGA($90\%$ sand and $10\%$ peat, v/v), and California-Z ($85\%$ sand and $15\%$ zeolite, v/v). Treatments were arranged in a randomized complete block with four replicates. Physical and chemical properties of the root zone and bentgrass performance were compared for the treatments. The California-Z treatment had the highest saturated hydraulic conductivity, field infiltration rate and the lowest bulk density. It also had the highest cation exchange capacity and plant available nutrient concentrations among the three treatments. The California-Z treatment produced bentgrass quality and color during green establishment and maturation that were equal to or higher than the California treatment, and consistently higher than the USGA treatment. The addition of an inorganic amendment to the California system improved physical and chemical properties of the root zone and improved quality and color of bentgrass during green establishment. During green maturation, creeping bentgrass in the California-Z treatment was equal (6 of 15 sampling dates) or $20\%$ higher (9 of 15 dates) in quality compared to the California system.

• Economic and Environmental Geology
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• v.41 no.2
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• pp.183-199
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• 2008

This study is focused on characterization of the physio-chemical and mineralogical properties, investigation of their vertical changes in the tailing profile of the Guryoung mining area, classification of the profile into distinct zones, and condition conceptual model of physio-chemical conditions and phases-water relationships controlling the element behaviors in the tailings. The upper part of the groundwater is characterized by the high contents of $Fe_2O_3$ and $SO_3$ for whole rock analysis, low pH, and the occurrence of jarosite, schwertmannite and Fe-oxyhydroxide as the secondary mineral phases. The tailing profile can be divided into the covering soil, jarosite zone, Fe-sulfate zone, Fe-oxyhydroxide and gypsum-bearing pyrite zone, calcite-bearing pyrite zone, soil zone, and weathered zone on the based of the geochemical and mineralogical characteristics. The profile can be sampled into the oxidized zone and the carbonate-rich primary zone with the dramatic changes in pH and the secondary mineral phases. The conceptual model proposed for the tailing profile can be summarized that the oxidation of pyrite is the most important reaction controlling the changes in pH, the dissolution of the primary silicates and carbonates, the precipitation of secondary mineral phases, acid-neutralizing, and heavy metal behaviors through the profile.

• Resources Recycling
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• v.21 no.5
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• pp.38-43
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• 2012

In this study, analysis of the flow of water in the soil environment was attempted to examine the changing patterns of permeability coefficient, k, presented in Darcy's law depending on soil particle size and the pattern of mixed soil that main factor affecting ground water flow in soil environment. In addition, permeability coefficient patterns depending on changes in water temperature and concentration were measured. As a result, the permeability for the soil particle size and mixing pattern is proportional to the size of the particles, and it was also influenced by the porosity depending on the mixed pattern and stratification. Especially compared with the single particle, mixing different sizes samples showed a lower k than the value of smaller single particles. In addition, permeability of groundwater increased with increasing temperature, also permeability decreased depending on the concentration of ions in groundwater. The results of this study were expected to use as meaningful data for the phenomenon reflects the characteristics of the soil to understand mobility of groundwater in soil environment.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.4
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• pp.280-284
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• 1989

The soil texture and the physico-chemical characteristics of 442,000ha reclaimable tide land in the south-western of korean peninsular were analysed. The subsidence which may occur as the soil ripened was studied. The results were as follows : 1. Among the 257,000ha of existing reclaimed tidal land 53.0% was tine silty soil and 36.0% coarse silty, 6.0% coarse loamy and 5.0% sandy soils, respectively. 2. Out of the total 442,000ha of reclaimable tidal land, 51.0% was coarse silty soil, and 20% sandy, 15.0% coarse loamy and 14.0% fine silty textural family, respectively. The coarse silty deposits were mainly distributed in the Gyeong gi and Jeonnam coast, while the coarse deposits(Coarse Loamy-sandy) exist in the Jeonbuk coastal area, but in the Chungnam areas there were various textural grades. 3. Reclaimable tidal Land in the south-western part of the peninsular was Classified into saline and alkaline soil. Electric Conductivity in saturation extract was extremely high that was 46~51 mmhos/cm, E.S.P was more than 25% and pH was ranged around 7.5~8.0 4. Reclaimed to cultivated field the subsidence reclaimable tide land to be expected when was about 18% in Soil and 21% in Sicl soils calculated down to 1.25m of the profile.